Merge branch 'lua'

Resolved Conflicts:
	NEWS

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

110 files changed, 28956 insertions, 1 deletions

diff --git a/NEWS b/NEWS
index f9b738c0..fb6179f5 100644
--- a/NEWS
+++ b/NEWS
@@ -14,6 +14,7 @@ Changes in 4.01:
 	  already has booted a CDROM or USB drive (Gert Hulselmans).
 	* Correct a severe memory overwrite bug (mainly related to the
 	  menu system.)
+	* lua.c32: Lua script interpreter, currently experimental.
 
 Changes in 4.00:
 	* Major code base changes; all filesystem rewritten in C.
diff --git a/com32/Makefile b/com32/Makefile
index 4f95017a..b090c403 100644
--- a/com32/Makefile
+++ b/com32/Makefile
@@ -1,4 +1,5 @@
 SUBDIRS = tools lib gpllib libutil modules mboot menu samples rosh cmenu \
-	  hdt gfxboot sysdump
+	  hdt gfxboot sysdump lua/src
+
 all tidy dist clean spotless install:
 	set -e; for d in $(SUBDIRS); do $(MAKE) -C $$d $@; done
diff --git a/com32/lua/COPYRIGHT b/com32/lua/COPYRIGHT
new file mode 100644
index 00000000..3a53e741
--- /dev/null
+++ b/com32/lua/COPYRIGHT
@@ -0,0 +1,34 @@
+Lua License
+-----------
+
+Lua is licensed under the terms of the MIT license reproduced below.
+This means that Lua is free software and can be used for both academic
+and commercial purposes at absolutely no cost.
+
+For details and rationale, see http://www.lua.org/license.html .
+
+===============================================================================
+
+Copyright (C) 1994-2008 Lua.org, PUC-Rio.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+
+===============================================================================
+
+(end of COPYRIGHT)
diff --git a/com32/lua/HISTORY b/com32/lua/HISTORY
new file mode 100644
index 00000000..ce0c95bc
--- /dev/null
+++ b/com32/lua/HISTORY
@@ -0,0 +1,183 @@
+HISTORY for Lua 5.1
+
+* Changes from version 5.0 to 5.1
+  -------------------------------
+  Language:
+  + new module system.
+  + new semantics for control variables of fors.
+  + new semantics for setn/getn.
+  + new syntax/semantics for varargs.
+  + new long strings and comments.
+  + new `mod' operator (`%')
+  + new length operator #t
+  + metatables for all types
+  API:
+  + new functions: lua_createtable, lua_get(set)field, lua_push(to)integer.
+  + user supplies memory allocator (lua_open becomes lua_newstate).
+  + luaopen_* functions must be called through Lua.
+  Implementation:
+  + new configuration scheme via luaconf.h.
+  + incremental garbage collection.
+  + better handling of end-of-line in the lexer.
+  + fully reentrant parser (new Lua function `load')
+  + better support for 64-bit machines.
+  + native loadlib support for Mac OS X.
+  + standard distribution in only one library (lualib.a merged into lua.a)
+
+* Changes from version 4.0 to 5.0
+  -------------------------------
+  Language:
+  + lexical scoping.
+  + Lua coroutines.
+  + standard libraries now packaged in tables.
+  + tags replaced by metatables and tag methods replaced by metamethods,
+    stored in metatables.
+  + proper tail calls.
+  + each function can have its own global table, which can be shared.
+  + new __newindex metamethod, called when we insert a new key into a table.
+  + new block comments: --[[ ... ]].
+  + new generic for.
+  + new weak tables.
+  + new boolean type.
+  + new syntax "local function".
+  + (f()) returns the first value returned by f.
+  + {f()} fills a table with all values returned by f.
+  + \n ignored in [[\n .
+  + fixed and-or priorities.
+  + more general syntax for function definition (e.g. function a.x.y:f()...end).
+  + more general syntax for function calls (e.g. (print or write)(9)).
+  + new functions (time/date, tmpfile, unpack, require, load*, etc.).
+  API:
+  + chunks are loaded by using lua_load; new luaL_loadfile and luaL_loadbuffer.
+  + introduced lightweight userdata, a simple "void*" without a metatable.
+  + new error handling protocol: the core no longer prints error messages;
+    all errors are reported to the caller on the stack.
+  + new lua_atpanic for host cleanup.
+  + new, signal-safe, hook scheme.
+  Implementation:
+  + new license: MIT.
+  + new, faster, register-based virtual machine.
+  + support for external multithreading and coroutines.
+  + new and consistent error message format.
+  + the core no longer needs "stdio.h" for anything (except for a single
+    use of sprintf to convert numbers to strings).
+  + lua.c now runs the environment variable LUA_INIT, if present. It can
+    be "@filename", to run a file, or the chunk itself.
+  + support for user extensions in lua.c.
+    sample implementation given for command line editing.
+  + new dynamic loading library, active by default on several platforms.
+  + safe garbage-collector metamethods.
+  + precompiled bytecodes checked for integrity (secure binary dostring).
+  + strings are fully aligned.
+  + position capture in string.find.
+  + read('*l') can read lines with embedded zeros.
+
+* Changes from version 3.2 to 4.0
+  -------------------------------
+  Language:
+  + new "break" and "for" statements (both numerical and for tables).
+  + uniform treatment of globals: globals are now stored in a Lua table.
+  + improved error messages.
+  + no more '$debug': full speed *and* full debug information.
+  + new read form: read(N) for next N bytes.
+  + general read patterns now deprecated.
+    (still available with -DCOMPAT_READPATTERNS.)
+  + all return values are passed as arguments for the last function
+    (old semantics still available with -DLUA_COMPAT_ARGRET)
+  + garbage collection tag methods for tables now deprecated.
+  + there is now only one tag method for order.
+  API:
+  + New API: fully re-entrant, simpler, and more efficient.
+  + New debug API.
+  Implementation:
+  + faster than ever: cleaner virtual machine and new hashing algorithm.
+  + non-recursive garbage-collector algorithm.
+  + reduced memory usage for programs with many strings.
+  + improved treatment for memory allocation errors.
+  + improved support for 16-bit machines (we hope).
+  + code now compiles unmodified as both ANSI C and C++.
+  + numbers in bases other than 10 are converted using strtoul.
+  + new -f option in Lua to support #! scripts.
+  + luac can now combine text and binaries.
+
+* Changes from version 3.1 to 3.2
+  -------------------------------
+  + redirected all output in Lua's core to _ERRORMESSAGE and _ALERT.
+  + increased limit on the number of constants and globals per function
+    (from 2^16 to 2^24).
+  + debugging info (lua_debug and hooks) moved into lua_state and new API
+    functions provided to get and set this info.
+  + new debug lib gives full debugging access within Lua.
+  + new table functions "foreachi", "sort", "tinsert", "tremove", "getn".
+  + new io functions "flush", "seek".
+
+* Changes from version 3.0 to 3.1
+  -------------------------------
+  + NEW FEATURE: anonymous functions with closures (via "upvalues").
+  + new syntax:
+    - local variables in chunks.
+    - better scope control with DO block END.
+    - constructors can now be also written: { record-part; list-part }.
+    - more general syntax for function calls and lvalues, e.g.:
+      f(x).y=1
+      o:f(x,y):g(z)
+      f"string" is sugar for f("string")
+  + strings may now contain arbitrary binary data (e.g., embedded zeros).
+  + major code re-organization and clean-up; reduced module interdependecies.
+  + no arbitrary limits on the total number of constants and globals.
+  + support for multiple global contexts.
+  + better syntax error messages.
+  + new traversal functions "foreach" and "foreachvar".
+  + the default for numbers is now double.
+    changing it to use floats or longs is easy.
+  + complete debug information stored in pre-compiled chunks.
+  + sample interpreter now prompts user when run interactively, and also
+    handles control-C interruptions gracefully.
+
+* Changes from version 2.5 to 3.0
+  -------------------------------
+  + NEW CONCEPT: "tag methods".
+    Tag methods replace fallbacks as the meta-mechanism for extending the
+    semantics of Lua. Whereas fallbacks had a global nature, tag methods
+    work on objects having the same tag (e.g., groups of tables).
+    Existing code that uses fallbacks should work without change.
+  + new, general syntax for constructors {[exp] = exp, ... }.
+  + support for handling variable number of arguments in functions (varargs).
+  + support for conditional compilation ($if ... $else ... $end).
+  + cleaner semantics in API simplifies host code.
+  + better support for writing libraries (auxlib.h).
+  + better type checking and error messages in the standard library.
+  + luac can now also undump.
+
+* Changes from version 2.4 to 2.5
+  -------------------------------
+  + io and string libraries are now based on pattern matching;
+    the old libraries are still available for compatibility
+  + dofile and dostring can now return values (via return statement)
+  + better support for 16- and 64-bit machines
+  + expanded documentation, with more examples
+
+* Changes from version 2.2 to 2.4
+  -------------------------------
+  + external compiler creates portable binary files that can be loaded faster
+  + interface for debugging and profiling
+  + new "getglobal" fallback
+  + new functions for handling references to Lua objects
+  + new functions in standard lib
+  + only one copy of each string is stored
+  + expanded documentation, with more examples
+
+* Changes from version 2.1 to 2.2
+  -------------------------------
+  + functions now may be declared with any "lvalue" as a name
+  + garbage collection of functions
+  + support for pipes
+
+* Changes from version 1.1 to 2.1
+  -------------------------------
+  + object-oriented support
+  + fallbacks
+  + simplified syntax for tables
+  + many internal improvements
+
+(end of HISTORY)
diff --git a/com32/lua/INSTALL b/com32/lua/INSTALL
new file mode 100644
index 00000000..17eb8aee
--- /dev/null
+++ b/com32/lua/INSTALL
@@ -0,0 +1,99 @@
+INSTALL for Lua 5.1
+
+* Building Lua
+  ------------
+  Lua is built in the src directory, but the build process can be
+  controlled from the top-level Makefile.
+
+  Building Lua on Unix systems should be very easy. First do "make" and
+  see if your platform is listed. If so, just do "make xxx", where xxx
+  is your platform name. The platforms currently supported are:
+    aix ansi bsd freebsd generic linux macosx mingw posix solaris
+
+  If your platform is not listed, try the closest one or posix, generic,
+  ansi, in this order.
+
+  See below for customization instructions and for instructions on how
+  to build with other Windows compilers.
+
+  If you want to check that Lua has been built correctly, do "make test"
+  after building Lua. Also, have a look at the example programs in test.
+
+* Installing Lua
+  --------------
+  Once you have built Lua, you may want to install it in an official
+  place in your system. In this case, do "make install". The official
+  place and the way to install files are defined in Makefile. You must
+  have the right permissions to install files.
+
+  If you want to build and install Lua in one step, do "make xxx install",
+  where xxx is your platform name.
+
+  If you want to install Lua locally, then do "make local". This will
+  create directories bin, include, lib, man, and install Lua there as
+  follows:
+
+    bin:	lua luac
+    include:	lua.h luaconf.h lualib.h lauxlib.h lua.hpp
+    lib:	liblua.a
+    man/man1:	lua.1 luac.1
+
+  These are the only directories you need for development.
+
+  There are man pages for lua and luac, in both nroff and html, and a
+  reference manual in html in doc, some sample code in test, and some
+  useful stuff in etc. You don't need these directories for development.
+
+  If you want to install Lua locally, but in some other directory, do
+  "make install INSTALL_TOP=xxx", where xxx is your chosen directory.
+
+  See below for instructions for Windows and other systems.
+
+* Customization
+  -------------
+  Three things can be customized by editing a file:
+    - Where and how to install Lua -- edit Makefile.
+    - How to build Lua -- edit src/Makefile.
+    - Lua features -- edit src/luaconf.h.
+
+  You don't actually need to edit the Makefiles because you may set the
+  relevant variables when invoking make.
+
+  On the other hand, if you need to select some Lua features, you'll need
+  to edit src/luaconf.h. The edited file will be the one installed, and
+  it will be used by any Lua clients that you build, to ensure consistency.
+
+  We strongly recommend that you enable dynamic loading. This is done
+  automatically for all platforms listed above that have this feature
+  (and also Windows). See src/luaconf.h and also src/Makefile.
+
+* Building Lua on Windows and other systems
+  -----------------------------------------
+  If you're not using the usual Unix tools, then the instructions for
+  building Lua depend on the compiler you use. You'll need to create
+  projects (or whatever your compiler uses) for building the library,
+  the interpreter, and the compiler, as follows:
+
+  library:	lapi.c lcode.c ldebug.c ldo.c ldump.c lfunc.c lgc.c llex.c
+		lmem.c lobject.c lopcodes.c lparser.c lstate.c lstring.c
+		ltable.c ltm.c lundump.c lvm.c lzio.c
+		lauxlib.c lbaselib.c ldblib.c liolib.c lmathlib.c loslib.c
+		ltablib.c lstrlib.c loadlib.c linit.c
+
+  interpreter:	library, lua.c
+
+  compiler:	library, luac.c print.c
+
+  If you use Visual Studio .NET, you can use etc/luavs.bat in its
+  "Command Prompt".
+
+  If all you want is to build the Lua interpreter, you may put all .c files
+  in a single project, except for luac.c and print.c. Or just use etc/all.c.
+
+  To use Lua as a library in your own programs, you'll need to know how to
+  create and use libraries with your compiler.
+
+  As mentioned above, you may edit luaconf.h to select some features before
+  building Lua.
+
+(end of INSTALL)
diff --git a/com32/lua/Makefile-orig b/com32/lua/Makefile-orig
new file mode 100644
index 00000000..fec20115
--- /dev/null
+++ b/com32/lua/Makefile-orig
@@ -0,0 +1,120 @@
+# makefile for installing Lua
+# see INSTALL for installation instructions
+# see src/Makefile and src/luaconf.h for further customization
+
+# == CHANGE THE SETTINGS BELOW TO SUIT YOUR ENVIRONMENT =======================
+
+# Your platform. See PLATS for possible values.
+PLAT= none
+
+# Where to install. The installation starts in the src directory, so take care
+# if INSTALL_TOP is not an absolute path. (Man pages are installed from the
+# doc directory.) You may want to make these paths consistent with LUA_ROOT,
+# LUA_LDIR, and LUA_CDIR in luaconf.h (and also with etc/lua.pc).
+#
+INSTALL_TOP= /usr/local
+INSTALL_BIN= $(INSTALL_TOP)/bin
+INSTALL_INC= $(INSTALL_TOP)/include
+INSTALL_LIB= $(INSTALL_TOP)/lib
+INSTALL_MAN= $(INSTALL_TOP)/man/man1
+INSTALL_LMOD= $(INSTALL_TOP)/share/lua/$V
+INSTALL_CMOD= $(INSTALL_TOP)/lib/lua/$V
+
+# How to install. If you don't have "install" (unlikely) then get install-sh at
+#	http://dev.w3.org/cvsweb/libwww/config/install-sh
+# or use cp instead.
+INSTALL_EXEC= $(INSTALL) -p -m 0755
+INSTALL_DATA= $(INSTALL) -p -m 0644
+
+# Utilities.
+INSTALL= install
+MKDIR= mkdir
+
+# == END OF USER SETTINGS. NO NEED TO CHANGE ANYTHING BELOW THIS LINE =========
+
+# Convenience platforms targets.
+PLATS= aix ansi bsd freebsd generic linux macosx mingw posix solaris
+
+# What to install.
+TO_BIN= lua luac
+TO_INC= lua.h luaconf.h lualib.h lauxlib.h ../etc/lua.hpp
+TO_LIB= liblua.a
+TO_MAN= lua.1 luac.1
+
+# Lua version and release.
+V= 5.1
+R= 5.1.3
+
+all:	$(PLAT)
+
+$(PLATS) clean:
+	cd src && $(MAKE) $@
+
+test:	dummy
+	src/lua test/hello.lua
+
+install: dummy
+	cd src && $(MKDIR) -p $(INSTALL_BIN) $(INSTALL_INC) $(INSTALL_LIB) $(INSTALL_MAN) $(INSTALL_LMOD) $(INSTALL_CMOD)
+	cd src && $(INSTALL_EXEC) $(TO_BIN) $(INSTALL_BIN)
+	cd src && $(INSTALL_DATA) $(TO_INC) $(INSTALL_INC)
+	cd src && $(INSTALL_DATA) $(TO_LIB) $(INSTALL_LIB)
+	cd doc && $(INSTALL_DATA) $(TO_MAN) $(INSTALL_MAN)
+
+local:
+	$(MAKE) install INSTALL_TOP=..
+
+none:
+	@echo "Please do"
+	@echo "   make PLATFORM"
+	@echo "where PLATFORM is one of these:"
+	@echo "   $(PLATS)"
+	@echo "See INSTALL for complete instructions."
+
+# make may get confused with test/ and INSTALL in a case-insensitive OS
+dummy:
+
+# echo config parameters
+echo:
+	@echo ""
+	@echo "These are the parameters currently set in src/Makefile to build Lua $R:"
+	@echo ""
+	@cd src && $(MAKE) -s echo
+	@echo ""
+	@echo "These are the parameters currently set in Makefile to install Lua $R:"
+	@echo ""
+	@echo "PLAT = $(PLAT)"
+	@echo "INSTALL_TOP = $(INSTALL_TOP)"
+	@echo "INSTALL_BIN = $(INSTALL_BIN)"
+	@echo "INSTALL_INC = $(INSTALL_INC)"
+	@echo "INSTALL_LIB = $(INSTALL_LIB)"
+	@echo "INSTALL_MAN = $(INSTALL_MAN)"
+	@echo "INSTALL_LMOD = $(INSTALL_LMOD)"
+	@echo "INSTALL_CMOD = $(INSTALL_CMOD)"
+	@echo "INSTALL_EXEC = $(INSTALL_EXEC)"
+	@echo "INSTALL_DATA = $(INSTALL_DATA)"
+	@echo ""
+	@echo "See also src/luaconf.h ."
+	@echo ""
+
+# echo private config parameters
+pecho:
+	@echo "V = $(V)"
+	@echo "R = $(R)"
+	@echo "TO_BIN = $(TO_BIN)"
+	@echo "TO_INC = $(TO_INC)"
+	@echo "TO_LIB = $(TO_LIB)"
+	@echo "TO_MAN = $(TO_MAN)"
+
+# echo config parameters as Lua code
+# uncomment the last sed expression if you want nil instead of empty strings
+lecho:
+	@echo "-- installation parameters for Lua $R"
+	@echo "VERSION = '$V'"
+	@echo "RELEASE = '$R'"
+	@$(MAKE) echo | grep = | sed -e 's/= /= "/' -e 's/$$/"/' #-e 's/""/nil/'
+	@echo "-- EOF"
+
+# list targets that do not create files (but not all makes understand .PHONY)
+.PHONY: all $(PLATS) clean test install local none dummy echo pecho lecho
+
+# (end of Makefile)
diff --git a/com32/lua/README b/com32/lua/README
new file mode 100644
index 00000000..11b4dff7
--- /dev/null
+++ b/com32/lua/README
@@ -0,0 +1,37 @@
+README for Lua 5.1
+
+See INSTALL for installation instructions.
+See HISTORY for a summary of changes since the last released version.
+
+* What is Lua?
+  ------------
+  Lua is a powerful, light-weight programming language designed for extending
+  applications. Lua is also frequently used as a general-purpose, stand-alone
+  language. Lua is free software.
+
+  For complete information, visit Lua's web site at http://www.lua.org/ .
+  For an executive summary, see http://www.lua.org/about.html .
+
+  Lua has been used in many different projects around the world.
+  For a short list, see http://www.lua.org/uses.html .
+
+* Availability
+  ------------
+  Lua is freely available for both academic and commercial purposes.
+  See COPYRIGHT and http://www.lua.org/license.html for details.
+  Lua can be downloaded at http://www.lua.org/download.html .
+
+* Installation
+  ------------
+  Lua is implemented in pure ANSI C, and compiles unmodified in all known
+  platforms that have an ANSI C compiler. In most Unix-like platforms, simply
+  do "make" with a suitable target. See INSTALL for detailed instructions.
+
+* Origin
+  ------
+  Lua is developed at Lua.org, a laboratory of the Department of Computer
+  Science of PUC-Rio (the Pontifical Catholic University of Rio de Janeiro
+  in Brazil).
+  For more information about the authors, see http://www.lua.org/authors.html .
+
+(end of README)
diff --git a/com32/lua/doc/amazon.gif b/com32/lua/doc/amazon.gif
new file mode 100644
index 00000000..f2586d57
--- /dev/null
+++ b/com32/lua/doc/amazon.gif
diff --git a/com32/lua/doc/contents.html b/com32/lua/doc/contents.html
new file mode 100644
index 00000000..8e58e18c
--- /dev/null
+++ b/com32/lua/doc/contents.html
@@ -0,0 +1,499 @@
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
+<HTML>
+<HEAD>
+<TITLE>Lua 5.1 Reference Manual - contents</TITLE>
+<LINK REL="stylesheet" TYPE="text/css" HREF="lua.css">
+<META HTTP-EQUIV="content-type" CONTENT="text/html; charset=iso-8859-1">
+<STYLE TYPE="text/css">
+ul {
+	list-style-type: none ;
+	list-style-position: outside ;
+}
+</STYLE>
+</HEAD>
+
+<BODY>
+
+<HR>
+<H1>
+<A HREF="http://www.lua.org/"><IMG SRC="logo.gif" ALT="" BORDER=0></A>
+Lua 5.1 Reference Manual
+</H1>
+
+This is an online version of
+<BLOCKQUOTE>
+<A HREF="http://www.amazon.com/exec/obidos/ASIN/8590379833/lua-indexmanual-20">
+<IMG SRC="cover.png" ALT="" TITLE="buy from Amazon" BORDER=1 ALIGN="left" HSPACE=12>
+</A>
+<B>Lua 5.1 Reference Manual</B>
+<BR>by R. Ierusalimschy, L. H. de Figueiredo, W. Celes
+<BR>Lua.org, August 2006
+<BR>ISBN 85-903798-3-3
+<BR><A HREF="http://www.amazon.com/exec/obidos/ASIN/8590379833/lua-indexmanual-20">
+<IMG SRC="amazon.gif" ALT="[Buy from Amazon]" BORDER=0></A>
+<BR CLEAR="all">
+</BLOCKQUOTE>
+<P>
+
+Buy a copy of this book and 
+<A HREF="http://www.lua.org/donations.html">help to support</A>
+the Lua project.
+<P>
+
+The reference manual is the official definition of the Lua language.
+For a complete introduction to Lua programming, see the book
+<A HREF="http://www.lua.org/docs.html#books">Programming in Lua</A>.
+<P>
+
+<A HREF="manual.html">start</A>
+&middot;
+<A HREF="#contents">contents</A>
+&middot;
+<A HREF="#index">index</A>
+&middot;
+<A HREF="http://www.lua.org/manual/5.1/pt/">português</A>
+&middot;
+<A HREF="http://www.lua.org/manual/5.1/es/">español</A>
+<HR>
+<SMALL>
+Copyright &copy; 2006-2008 Lua.org, PUC-Rio.
+Freely available under the terms of the
+<a href="http://www.lua.org/license.html#5">Lua license</a>.
+</SMALL>
+<P>
+
+<H2><A NAME="contents">Contents</A></H2>
+<UL style="padding: 0">
+<LI><A HREF="manual.html">1 - Introduction</A>
+<P>
+<LI><A HREF="manual.html#2">2 - The Language</A>
+<UL>
+<LI><A HREF="manual.html#2.1">2.1 - Lexical Conventions</A>
+<LI><A HREF="manual.html#2.2">2.2 - Values and Types</A>
+<UL>
+<LI><A HREF="manual.html#2.2.1">2.2.1 - Coercion</A>
+</UL>
+<LI><A HREF="manual.html#2.3">2.3 - Variables</A>
+<LI><A HREF="manual.html#2.4">2.4 - Statements</A>
+<UL>
+<LI><A HREF="manual.html#2.4.1">2.4.1 - Chunks</A>
+<LI><A HREF="manual.html#2.4.2">2.4.2 - Blocks</A>
+<LI><A HREF="manual.html#2.4.3">2.4.3 - Assignment</A>
+<LI><A HREF="manual.html#2.4.4">2.4.4 - Control Structures</A>
+<LI><A HREF="manual.html#2.4.5">2.4.5 - For Statement</A>
+<LI><A HREF="manual.html#2.4.6">2.4.6 - Function Calls as Statements</A>
+<LI><A HREF="manual.html#2.4.7">2.4.7 - Local Declarations</A>
+</UL>
+<LI><A HREF="manual.html#2.5">2.5 - Expressions</A>
+<UL>
+<LI><A HREF="manual.html#2.5.1">2.5.1 - Arithmetic Operators</A>
+<LI><A HREF="manual.html#2.5.2">2.5.2 - Relational Operators</A>
+<LI><A HREF="manual.html#2.5.3">2.5.3 - Logical Operators</A>
+<LI><A HREF="manual.html#2.5.4">2.5.4 - Concatenation</A>
+<LI><A HREF="manual.html#2.5.5">2.5.5 - The Length Operator</A>
+<LI><A HREF="manual.html#2.5.6">2.5.6 - Precedence</A>
+<LI><A HREF="manual.html#2.5.7">2.5.7 - Table Constructors</A>
+<LI><A HREF="manual.html#2.5.8">2.5.8 - Function Calls</A>
+<LI><A HREF="manual.html#2.5.9">2.5.9 - Function Definitions</A>
+</UL>
+<LI><A HREF="manual.html#2.6">2.6 - Visibility Rules</A>
+<LI><A HREF="manual.html#2.7">2.7 - Error Handling</A>
+<LI><A HREF="manual.html#2.8">2.8 - Metatables</A>
+<LI><A HREF="manual.html#2.9">2.9 - Environments</A>
+<LI><A HREF="manual.html#2.10">2.10 - Garbage Collection</A>
+<UL>
+<LI><A HREF="manual.html#2.10.1">2.10.1 - Garbage-Collection Metamethods</A>
+<LI><A HREF="manual.html#2.10.2">2.10.2 - Weak Tables</A>
+</UL>
+<LI><A HREF="manual.html#2.11">2.11 - Coroutines</A>
+</UL>
+<P>
+<LI><A HREF="manual.html#3">3 - The Application Program Interface</A>
+<UL>
+<LI><A HREF="manual.html#3.1">3.1 - The Stack</A>
+<LI><A HREF="manual.html#3.2">3.2 - Stack Size</A>
+<LI><A HREF="manual.html#3.3">3.3 - Pseudo-Indices</A>
+<LI><A HREF="manual.html#3.4">3.4 - C Closures</A>
+<LI><A HREF="manual.html#3.5">3.5 - Registry</A>
+<LI><A HREF="manual.html#3.6">3.6 - Error Handling in C</A>
+<LI><A HREF="manual.html#3.7">3.7 - Functions and Types</A>
+<LI><A HREF="manual.html#3.8">3.8 - The Debug Interface</A>
+</UL>
+<P>
+<LI><A HREF="manual.html#4">4 - The Auxiliary Library</A>
+<UL>
+<LI><A HREF="manual.html#4.1">4.1 - Functions and Types</A>
+</UL>
+<P>
+<LI><A HREF="manual.html#5">5 - Standard Libraries</A>
+<UL>
+<LI><A HREF="manual.html#5.1">5.1 - Basic Functions</A>
+<LI><A HREF="manual.html#5.2">5.2 - Coroutine Manipulation</A>
+<LI><A HREF="manual.html#5.3">5.3 - Modules</A>
+<LI><A HREF="manual.html#5.4">5.4 - String Manipulation</A>
+<UL>
+<LI><A HREF="manual.html#5.4.1">5.4.1 - Patterns</A>
+</UL>
+<LI><A HREF="manual.html#5.5">5.5 - Table Manipulation</A>
+<LI><A HREF="manual.html#5.6">5.6 - Mathematical Functions</A>
+<LI><A HREF="manual.html#5.7">5.7 - Input and Output Facilities</A>
+<LI><A HREF="manual.html#5.8">5.8 - Operating System Facilities</A>
+<LI><A HREF="manual.html#5.9">5.9 - The Debug Library</A>
+</UL>
+<P>
+<LI><A HREF="manual.html#6">6 - Lua Stand-alone</A>
+<P>
+<LI><A HREF="manual.html#7">7 - Incompatibilities with the Previous Version</A>
+<UL>
+<LI><A HREF="manual.html#7.1">7.1 - Changes in the Language</A>
+<LI><A HREF="manual.html#7.2">7.2 - Changes in the Libraries</A>
+<LI><A HREF="manual.html#7.3">7.3 - Changes in the API</A>
+</UL>
+<P>
+<LI><A HREF="manual.html#8">8 - The Complete Syntax of Lua</A>
+</UL>
+
+<H2><A NAME="index">Index</A></H2>
+<TABLE WIDTH="100%">
+<TR VALIGN="top">
+<TD>
+<H3><A NAME="functions">Lua functions</A></H3>
+<A HREF="manual.html#pdf-_G">_G</A><BR>
+<A HREF="manual.html#pdf-_VERSION">_VERSION</A><BR>
+<A HREF="manual.html#pdf-assert">assert</A><BR>
+<A HREF="manual.html#pdf-collectgarbage">collectgarbage</A><BR>
+<A HREF="manual.html#pdf-dofile">dofile</A><BR>
+<A HREF="manual.html#pdf-error">error</A><BR>
+<A HREF="manual.html#pdf-getfenv">getfenv</A><BR>
+<A HREF="manual.html#pdf-getmetatable">getmetatable</A><BR>
+<A HREF="manual.html#pdf-ipairs">ipairs</A><BR>
+<A HREF="manual.html#pdf-load">load</A><BR>
+<A HREF="manual.html#pdf-loadfile">loadfile</A><BR>
+<A HREF="manual.html#pdf-loadstring">loadstring</A><BR>
+<A HREF="manual.html#pdf-module">module</A><BR>
+<A HREF="manual.html#pdf-next">next</A><BR>
+<A HREF="manual.html#pdf-pairs">pairs</A><BR>
+<A HREF="manual.html#pdf-pcall">pcall</A><BR>
+<A HREF="manual.html#pdf-print">print</A><BR>
+<A HREF="manual.html#pdf-rawequal">rawequal</A><BR>
+<A HREF="manual.html#pdf-rawget">rawget</A><BR>
+<A HREF="manual.html#pdf-rawset">rawset</A><BR>
+<A HREF="manual.html#pdf-require">require</A><BR>
+<A HREF="manual.html#pdf-select">select</A><BR>
+<A HREF="manual.html#pdf-setfenv">setfenv</A><BR>
+<A HREF="manual.html#pdf-setmetatable">setmetatable</A><BR>
+<A HREF="manual.html#pdf-tonumber">tonumber</A><BR>
+<A HREF="manual.html#pdf-tostring">tostring</A><BR>
+<A HREF="manual.html#pdf-type">type</A><BR>
+<A HREF="manual.html#pdf-unpack">unpack</A><BR>
+<A HREF="manual.html#pdf-xpcall">xpcall</A><BR>
+<P>
+
+<A HREF="manual.html#pdf-coroutine.create">coroutine.create</A><BR>
+<A HREF="manual.html#pdf-coroutine.resume">coroutine.resume</A><BR>
+<A HREF="manual.html#pdf-coroutine.running">coroutine.running</A><BR>
+<A HREF="manual.html#pdf-coroutine.status">coroutine.status</A><BR>
+<A HREF="manual.html#pdf-coroutine.wrap">coroutine.wrap</A><BR>
+<A HREF="manual.html#pdf-coroutine.yield">coroutine.yield</A><BR>
+<P>
+
+<A HREF="manual.html#pdf-debug.debug">debug.debug</A><BR>
+<A HREF="manual.html#pdf-debug.getfenv">debug.getfenv</A><BR>
+<A HREF="manual.html#pdf-debug.gethook">debug.gethook</A><BR>
+<A HREF="manual.html#pdf-debug.getinfo">debug.getinfo</A><BR>
+<A HREF="manual.html#pdf-debug.getlocal">debug.getlocal</A><BR>
+<A HREF="manual.html#pdf-debug.getmetatable">debug.getmetatable</A><BR>
+<A HREF="manual.html#pdf-debug.getregistry">debug.getregistry</A><BR>
+<A HREF="manual.html#pdf-debug.getupvalue">debug.getupvalue</A><BR>
+<A HREF="manual.html#pdf-debug.setfenv">debug.setfenv</A><BR>
+<A HREF="manual.html#pdf-debug.sethook">debug.sethook</A><BR>
+<A HREF="manual.html#pdf-debug.setlocal">debug.setlocal</A><BR>
+<A HREF="manual.html#pdf-debug.setmetatable">debug.setmetatable</A><BR>
+<A HREF="manual.html#pdf-debug.setupvalue">debug.setupvalue</A><BR>
+<A HREF="manual.html#pdf-debug.traceback">debug.traceback</A><BR>
+
+</TD>
+<TD>
+<H3>&nbsp;</H3>
+<A HREF="manual.html#pdf-file:close">file:close</A><BR>
+<A HREF="manual.html#pdf-file:flush">file:flush</A><BR>
+<A HREF="manual.html#pdf-file:lines">file:lines</A><BR>
+<A HREF="manual.html#pdf-file:read">file:read</A><BR>
+<A HREF="manual.html#pdf-file:seek">file:seek</A><BR>
+<A HREF="manual.html#pdf-file:setvbuf">file:setvbuf</A><BR>
+<A HREF="manual.html#pdf-file:write">file:write</A><BR>
+<P>
+
+<A HREF="manual.html#pdf-io.close">io.close</A><BR>
+<A HREF="manual.html#pdf-io.flush">io.flush</A><BR>
+<A HREF="manual.html#pdf-io.input">io.input</A><BR>
+<A HREF="manual.html#pdf-io.lines">io.lines</A><BR>
+<A HREF="manual.html#pdf-io.open">io.open</A><BR>
+<A HREF="manual.html#pdf-io.output">io.output</A><BR>
+<A HREF="manual.html#pdf-io.popen">io.popen</A><BR>
+<A HREF="manual.html#pdf-io.read">io.read</A><BR>
+<A HREF="manual.html#pdf-io.stderr">io.stderr</A><BR>
+<A HREF="manual.html#pdf-io.stdin">io.stdin</A><BR>
+<A HREF="manual.html#pdf-io.stdout">io.stdout</A><BR>
+<A HREF="manual.html#pdf-io.tmpfile">io.tmpfile</A><BR>
+<A HREF="manual.html#pdf-io.type">io.type</A><BR>
+<A HREF="manual.html#pdf-io.write">io.write</A><BR>
+<P>
+
+<A HREF="manual.html#pdf-math.abs">math.abs</A><BR>
+<A HREF="manual.html#pdf-math.acos">math.acos</A><BR>
+<A HREF="manual.html#pdf-math.asin">math.asin</A><BR>
+<A HREF="manual.html#pdf-math.atan">math.atan</A><BR>
+<A HREF="manual.html#pdf-math.atan2">math.atan2</A><BR>
+<A HREF="manual.html#pdf-math.ceil">math.ceil</A><BR>
+<A HREF="manual.html#pdf-math.cos">math.cos</A><BR>
+<A HREF="manual.html#pdf-math.cosh">math.cosh</A><BR>
+<A HREF="manual.html#pdf-math.deg">math.deg</A><BR>
+<A HREF="manual.html#pdf-math.exp">math.exp</A><BR>
+<A HREF="manual.html#pdf-math.floor">math.floor</A><BR>
+<A HREF="manual.html#pdf-math.fmod">math.fmod</A><BR>
+<A HREF="manual.html#pdf-math.frexp">math.frexp</A><BR>
+<A HREF="manual.html#pdf-math.huge">math.huge</A><BR>
+<A HREF="manual.html#pdf-math.ldexp">math.ldexp</A><BR>
+<A HREF="manual.html#pdf-math.log">math.log</A><BR>
+<A HREF="manual.html#pdf-math.log10">math.log10</A><BR>
+<A HREF="manual.html#pdf-math.max">math.max</A><BR>
+<A HREF="manual.html#pdf-math.min">math.min</A><BR>
+<A HREF="manual.html#pdf-math.modf">math.modf</A><BR>
+<A HREF="manual.html#pdf-math.pi">math.pi</A><BR>
+<A HREF="manual.html#pdf-math.pow">math.pow</A><BR>
+<A HREF="manual.html#pdf-math.rad">math.rad</A><BR>
+<A HREF="manual.html#pdf-math.random">math.random</A><BR>
+<A HREF="manual.html#pdf-math.randomseed">math.randomseed</A><BR>
+<A HREF="manual.html#pdf-math.sin">math.sin</A><BR>
+<A HREF="manual.html#pdf-math.sinh">math.sinh</A><BR>
+<A HREF="manual.html#pdf-math.sqrt">math.sqrt</A><BR>
+<A HREF="manual.html#pdf-math.tan">math.tan</A><BR>
+<A HREF="manual.html#pdf-math.tanh">math.tanh</A><BR>
+<P>
+
+<A HREF="manual.html#pdf-os.clock">os.clock</A><BR>
+<A HREF="manual.html#pdf-os.date">os.date</A><BR>
+<A HREF="manual.html#pdf-os.difftime">os.difftime</A><BR>
+<A HREF="manual.html#pdf-os.execute">os.execute</A><BR>
+<A HREF="manual.html#pdf-os.exit">os.exit</A><BR>
+<A HREF="manual.html#pdf-os.getenv">os.getenv</A><BR>
+<A HREF="manual.html#pdf-os.remove">os.remove</A><BR>
+<A HREF="manual.html#pdf-os.rename">os.rename</A><BR>
+<A HREF="manual.html#pdf-os.setlocale">os.setlocale</A><BR>
+<A HREF="manual.html#pdf-os.time">os.time</A><BR>
+<A HREF="manual.html#pdf-os.tmpname">os.tmpname</A><BR>
+<P>
+
+<A HREF="manual.html#pdf-package.cpath">package.cpath</A><BR>
+<A HREF="manual.html#pdf-package.loaded">package.loaded</A><BR>
+<A HREF="manual.html#pdf-package.loaders">package.loaders</A><BR>
+<A HREF="manual.html#pdf-package.loadlib">package.loadlib</A><BR>
+<A HREF="manual.html#pdf-package.path">package.path</A><BR>
+<A HREF="manual.html#pdf-package.preload">package.preload</A><BR>
+<A HREF="manual.html#pdf-package.seeall">package.seeall</A><BR>
+<P>
+
+<A HREF="manual.html#pdf-string.byte">string.byte</A><BR>
+<A HREF="manual.html#pdf-string.char">string.char</A><BR>
+<A HREF="manual.html#pdf-string.dump">string.dump</A><BR>
+<A HREF="manual.html#pdf-string.find">string.find</A><BR>
+<A HREF="manual.html#pdf-string.format">string.format</A><BR>
+<A HREF="manual.html#pdf-string.gmatch">string.gmatch</A><BR>
+<A HREF="manual.html#pdf-string.gsub">string.gsub</A><BR>
+<A HREF="manual.html#pdf-string.len">string.len</A><BR>
+<A HREF="manual.html#pdf-string.lower">string.lower</A><BR>
+<A HREF="manual.html#pdf-string.match">string.match</A><BR>
+<A HREF="manual.html#pdf-string.rep">string.rep</A><BR>
+<A HREF="manual.html#pdf-string.reverse">string.reverse</A><BR>
+<A HREF="manual.html#pdf-string.sub">string.sub</A><BR>
+<A HREF="manual.html#pdf-string.upper">string.upper</A><BR>
+<P>
+
+<A HREF="manual.html#pdf-table.concat">table.concat</A><BR>
+<A HREF="manual.html#pdf-table.insert">table.insert</A><BR>
+<A HREF="manual.html#pdf-table.maxn">table.maxn</A><BR>
+<A HREF="manual.html#pdf-table.remove">table.remove</A><BR>
+<A HREF="manual.html#pdf-table.sort">table.sort</A><BR>
+
+</TD>
+<TD>
+<H3>C API</H3>
+<A HREF="manual.html#lua_Alloc">lua_Alloc</A><BR>
+<A HREF="manual.html#lua_CFunction">lua_CFunction</A><BR>
+<A HREF="manual.html#lua_Debug">lua_Debug</A><BR>
+<A HREF="manual.html#lua_Hook">lua_Hook</A><BR>
+<A HREF="manual.html#lua_Integer">lua_Integer</A><BR>
+<A HREF="manual.html#lua_Number">lua_Number</A><BR>
+<A HREF="manual.html#lua_Reader">lua_Reader</A><BR>
+<A HREF="manual.html#lua_State">lua_State</A><BR>
+<A HREF="manual.html#lua_Writer">lua_Writer</A><BR>
+<P>
+
+<A HREF="manual.html#lua_atpanic">lua_atpanic</A><BR>
+<A HREF="manual.html#lua_call">lua_call</A><BR>
+<A HREF="manual.html#lua_checkstack">lua_checkstack</A><BR>
+<A HREF="manual.html#lua_close">lua_close</A><BR>
+<A HREF="manual.html#lua_concat">lua_concat</A><BR>
+<A HREF="manual.html#lua_cpcall">lua_cpcall</A><BR>
+<A HREF="manual.html#lua_createtable">lua_createtable</A><BR>
+<A HREF="manual.html#lua_dump">lua_dump</A><BR>
+<A HREF="manual.html#lua_equal">lua_equal</A><BR>
+<A HREF="manual.html#lua_error">lua_error</A><BR>
+<A HREF="manual.html#lua_gc">lua_gc</A><BR>
+<A HREF="manual.html#lua_getallocf">lua_getallocf</A><BR>
+<A HREF="manual.html#lua_getfenv">lua_getfenv</A><BR>
+<A HREF="manual.html#lua_getfield">lua_getfield</A><BR>
+<A HREF="manual.html#lua_getglobal">lua_getglobal</A><BR>
+<A HREF="manual.html#lua_gethook">lua_gethook</A><BR>
+<A HREF="manual.html#lua_gethookcount">lua_gethookcount</A><BR>
+<A HREF="manual.html#lua_gethookmask">lua_gethookmask</A><BR>
+<A HREF="manual.html#lua_getinfo">lua_getinfo</A><BR>
+<A HREF="manual.html#lua_getlocal">lua_getlocal</A><BR>
+<A HREF="manual.html#lua_getmetatable">lua_getmetatable</A><BR>
+<A HREF="manual.html#lua_getstack">lua_getstack</A><BR>
+<A HREF="manual.html#lua_gettable">lua_gettable</A><BR>
+<A HREF="manual.html#lua_gettop">lua_gettop</A><BR>
+<A HREF="manual.html#lua_getupvalue">lua_getupvalue</A><BR>
+<A HREF="manual.html#lua_insert">lua_insert</A><BR>
+<A HREF="manual.html#lua_isboolean">lua_isboolean</A><BR>
+<A HREF="manual.html#lua_iscfunction">lua_iscfunction</A><BR>
+<A HREF="manual.html#lua_isfunction">lua_isfunction</A><BR>
+<A HREF="manual.html#lua_islightuserdata">lua_islightuserdata</A><BR>
+<A HREF="manual.html#lua_isnil">lua_isnil</A><BR>
+<A HREF="manual.html#lua_isnone">lua_isnone</A><BR>
+<A HREF="manual.html#lua_isnoneornil">lua_isnoneornil</A><BR>
+<A HREF="manual.html#lua_isnumber">lua_isnumber</A><BR>
+<A HREF="manual.html#lua_isstring">lua_isstring</A><BR>
+<A HREF="manual.html#lua_istable">lua_istable</A><BR>
+<A HREF="manual.html#lua_isthread">lua_isthread</A><BR>
+<A HREF="manual.html#lua_isuserdata">lua_isuserdata</A><BR>
+<A HREF="manual.html#lua_lessthan">lua_lessthan</A><BR>
+<A HREF="manual.html#lua_load">lua_load</A><BR>
+<A HREF="manual.html#lua_newstate">lua_newstate</A><BR>
+<A HREF="manual.html#lua_newtable">lua_newtable</A><BR>
+<A HREF="manual.html#lua_newthread">lua_newthread</A><BR>
+<A HREF="manual.html#lua_newuserdata">lua_newuserdata</A><BR>
+<A HREF="manual.html#lua_next">lua_next</A><BR>
+<A HREF="manual.html#lua_objlen">lua_objlen</A><BR>
+<A HREF="manual.html#lua_pcall">lua_pcall</A><BR>
+<A HREF="manual.html#lua_pop">lua_pop</A><BR>
+<A HREF="manual.html#lua_pushboolean">lua_pushboolean</A><BR>
+<A HREF="manual.html#lua_pushcclosure">lua_pushcclosure</A><BR>
+<A HREF="manual.html#lua_pushcfunction">lua_pushcfunction</A><BR>
+<A HREF="manual.html#lua_pushfstring">lua_pushfstring</A><BR>
+<A HREF="manual.html#lua_pushinteger">lua_pushinteger</A><BR>
+<A HREF="manual.html#lua_pushlightuserdata">lua_pushlightuserdata</A><BR>
+<A HREF="manual.html#lua_pushliteral">lua_pushliteral</A><BR>
+<A HREF="manual.html#lua_pushlstring">lua_pushlstring</A><BR>
+<A HREF="manual.html#lua_pushnil">lua_pushnil</A><BR>
+<A HREF="manual.html#lua_pushnumber">lua_pushnumber</A><BR>
+<A HREF="manual.html#lua_pushstring">lua_pushstring</A><BR>
+<A HREF="manual.html#lua_pushthread">lua_pushthread</A><BR>
+<A HREF="manual.html#lua_pushvalue">lua_pushvalue</A><BR>
+<A HREF="manual.html#lua_pushvfstring">lua_pushvfstring</A><BR>
+<A HREF="manual.html#lua_rawequal">lua_rawequal</A><BR>
+<A HREF="manual.html#lua_rawget">lua_rawget</A><BR>
+<A HREF="manual.html#lua_rawgeti">lua_rawgeti</A><BR>
+<A HREF="manual.html#lua_rawset">lua_rawset</A><BR>
+<A HREF="manual.html#lua_rawseti">lua_rawseti</A><BR>
+<A HREF="manual.html#lua_register">lua_register</A><BR>
+<A HREF="manual.html#lua_remove">lua_remove</A><BR>
+<A HREF="manual.html#lua_replace">lua_replace</A><BR>
+<A HREF="manual.html#lua_resume">lua_resume</A><BR>
+<A HREF="manual.html#lua_setallocf">lua_setallocf</A><BR>
+<A HREF="manual.html#lua_setfenv">lua_setfenv</A><BR>
+<A HREF="manual.html#lua_setfield">lua_setfield</A><BR>
+<A HREF="manual.html#lua_setglobal">lua_setglobal</A><BR>
+<A HREF="manual.html#lua_sethook">lua_sethook</A><BR>
+<A HREF="manual.html#lua_setlocal">lua_setlocal</A><BR>
+<A HREF="manual.html#lua_setmetatable">lua_setmetatable</A><BR>
+<A HREF="manual.html#lua_settable">lua_settable</A><BR>
+<A HREF="manual.html#lua_settop">lua_settop</A><BR>
+<A HREF="manual.html#lua_setupvalue">lua_setupvalue</A><BR>
+<A HREF="manual.html#lua_status">lua_status</A><BR>
+<A HREF="manual.html#lua_toboolean">lua_toboolean</A><BR>
+<A HREF="manual.html#lua_tocfunction">lua_tocfunction</A><BR>
+<A HREF="manual.html#lua_tointeger">lua_tointeger</A><BR>
+<A HREF="manual.html#lua_tolstring">lua_tolstring</A><BR>
+<A HREF="manual.html#lua_tonumber">lua_tonumber</A><BR>
+<A HREF="manual.html#lua_topointer">lua_topointer</A><BR>
+<A HREF="manual.html#lua_tostring">lua_tostring</A><BR>
+<A HREF="manual.html#lua_tothread">lua_tothread</A><BR>
+<A HREF="manual.html#lua_touserdata">lua_touserdata</A><BR>
+<A HREF="manual.html#lua_type">lua_type</A><BR>
+<A HREF="manual.html#lua_typename">lua_typename</A><BR>
+<A HREF="manual.html#lua_upvalueindex">lua_upvalueindex</A><BR>
+<A HREF="manual.html#lua_xmove">lua_xmove</A><BR>
+<A HREF="manual.html#lua_yield">lua_yield</A><BR>
+
+</TD>
+<TD>
+<H3>auxiliary library</H3>
+<A HREF="manual.html#luaL_Buffer">luaL_Buffer</A><BR>
+<A HREF="manual.html#luaL_Reg">luaL_Reg</A><BR>
+<P>
+
+<A HREF="manual.html#luaL_addchar">luaL_addchar</A><BR>
+<A HREF="manual.html#luaL_addlstring">luaL_addlstring</A><BR>
+<A HREF="manual.html#luaL_addsize">luaL_addsize</A><BR>
+<A HREF="manual.html#luaL_addstring">luaL_addstring</A><BR>
+<A HREF="manual.html#luaL_addvalue">luaL_addvalue</A><BR>
+<A HREF="manual.html#luaL_argcheck">luaL_argcheck</A><BR>
+<A HREF="manual.html#luaL_argerror">luaL_argerror</A><BR>
+<A HREF="manual.html#luaL_buffinit">luaL_buffinit</A><BR>
+<A HREF="manual.html#luaL_callmeta">luaL_callmeta</A><BR>
+<A HREF="manual.html#luaL_checkany">luaL_checkany</A><BR>
+<A HREF="manual.html#luaL_checkint">luaL_checkint</A><BR>
+<A HREF="manual.html#luaL_checkinteger">luaL_checkinteger</A><BR>
+<A HREF="manual.html#luaL_checklong">luaL_checklong</A><BR>
+<A HREF="manual.html#luaL_checklstring">luaL_checklstring</A><BR>
+<A HREF="manual.html#luaL_checknumber">luaL_checknumber</A><BR>
+<A HREF="manual.html#luaL_checkoption">luaL_checkoption</A><BR>
+<A HREF="manual.html#luaL_checkstack">luaL_checkstack</A><BR>
+<A HREF="manual.html#luaL_checkstring">luaL_checkstring</A><BR>
+<A HREF="manual.html#luaL_checktype">luaL_checktype</A><BR>
+<A HREF="manual.html#luaL_checkudata">luaL_checkudata</A><BR>
+<A HREF="manual.html#luaL_dofile">luaL_dofile</A><BR>
+<A HREF="manual.html#luaL_dostring">luaL_dostring</A><BR>
+<A HREF="manual.html#luaL_error">luaL_error</A><BR>
+<A HREF="manual.html#luaL_getmetafield">luaL_getmetafield</A><BR>
+<A HREF="manual.html#luaL_getmetatable">luaL_getmetatable</A><BR>
+<A HREF="manual.html#luaL_gsub">luaL_gsub</A><BR>
+<A HREF="manual.html#luaL_loadbuffer">luaL_loadbuffer</A><BR>
+<A HREF="manual.html#luaL_loadfile">luaL_loadfile</A><BR>
+<A HREF="manual.html#luaL_loadstring">luaL_loadstring</A><BR>
+<A HREF="manual.html#luaL_newmetatable">luaL_newmetatable</A><BR>
+<A HREF="manual.html#luaL_newstate">luaL_newstate</A><BR>
+<A HREF="manual.html#luaL_openlibs">luaL_openlibs</A><BR>
+<A HREF="manual.html#luaL_optint">luaL_optint</A><BR>
+<A HREF="manual.html#luaL_optinteger">luaL_optinteger</A><BR>
+<A HREF="manual.html#luaL_optlong">luaL_optlong</A><BR>
+<A HREF="manual.html#luaL_optlstring">luaL_optlstring</A><BR>
+<A HREF="manual.html#luaL_optnumber">luaL_optnumber</A><BR>
+<A HREF="manual.html#luaL_optstring">luaL_optstring</A><BR>
+<A HREF="manual.html#luaL_prepbuffer">luaL_prepbuffer</A><BR>
+<A HREF="manual.html#luaL_pushresult">luaL_pushresult</A><BR>
+<A HREF="manual.html#luaL_ref">luaL_ref</A><BR>
+<A HREF="manual.html#luaL_register">luaL_register</A><BR>
+<A HREF="manual.html#luaL_typename">luaL_typename</A><BR>
+<A HREF="manual.html#luaL_typerror">luaL_typerror</A><BR>
+<A HREF="manual.html#luaL_unref">luaL_unref</A><BR>
+<A HREF="manual.html#luaL_where">luaL_where</A><BR>
+
+</TD>
+</TR>
+</TABLE>
+<P>
+
+<HR>
+<SMALL>
+Last update:
+Sat Jan 19 13:24:29 BRST 2008
+</SMALL>
+<!--
+Last change: revised for Lua 5.1.3
+-->
+
+</BODY>
+</HTML>
diff --git a/com32/lua/doc/cover.png b/com32/lua/doc/cover.png
new file mode 100644
index 00000000..2dbb1981
--- /dev/null
+++ b/com32/lua/doc/cover.png
diff --git a/com32/lua/doc/logo.gif b/com32/lua/doc/logo.gif
new file mode 100644
index 00000000..2f5e4ac2
--- /dev/null
+++ b/com32/lua/doc/logo.gif
diff --git a/com32/lua/doc/lua.1 b/com32/lua/doc/lua.1
new file mode 100644
index 00000000..24809cc6
--- /dev/null
+++ b/com32/lua/doc/lua.1
@@ -0,0 +1,163 @@
+.\" $Id: lua.man,v 1.11 2006/01/06 16:03:34 lhf Exp $
+.TH LUA 1 "$Date: 2006/01/06 16:03:34 $"
+.SH NAME
+lua \- Lua interpreter
+.SH SYNOPSIS
+.B lua
+[
+.I options
+]
+[
+.I script
+[
+.I args
+]
+]
+.SH DESCRIPTION
+.B lua
+is the stand-alone Lua interpreter.
+It loads and executes Lua programs,
+either in textual source form or
+in precompiled binary form.
+(Precompiled binaries are output by
+.BR luac ,
+the Lua compiler.)
+.B lua
+can be used as a batch interpreter and also interactively.
+.LP
+The given
+.I options
+(see below)
+are executed and then
+the Lua program in file
+.I script
+is loaded and executed.
+The given
+.I args
+are available to
+.I script
+as strings in a global table named
+.BR arg .
+If these arguments contain spaces or other characters special to the shell,
+then they should be quoted
+(but note that the quotes will be removed by the shell).
+The arguments in
+.B arg
+start at 0,
+which contains the string
+.RI ' script '.
+The index of the last argument is stored in
+.BR arg.n .
+The arguments given in the command line before
+.IR script ,
+including the name of the interpreter,
+are available in negative indices in
+.BR arg .
+.LP
+At the very start,
+before even handling the command line,
+.B lua
+executes the contents of the environment variable
+.BR LUA_INIT ,
+if it is defined.
+If the value of
+.B LUA_INIT
+is of the form
+.RI '@ filename ',
+then
+.I filename
+is executed.
+Otherwise, the string is assumed to be a Lua statement and is executed.
+.LP
+Options start with
+.B '\-'
+and are described below.
+You can use
+.B "'\--'"
+to signal the end of options.
+.LP
+If no arguments are given,
+then
+.B "\-v \-i"
+is assumed when the standard input is a terminal;
+otherwise,
+.B "\-"
+is assumed.
+.LP
+In interactive mode,
+.B lua
+prompts the user,
+reads lines from the standard input,
+and executes them as they are read.
+If a line does not contain a complete statement,
+then a secondary prompt is displayed and
+lines are read until a complete statement is formed or
+a syntax error is found.
+So, one way to interrupt the reading of an incomplete statement is
+to force a syntax error:
+adding a
+.B ';' 
+in the middle of a statement is a sure way of forcing a syntax error
+(except inside multiline strings and comments; these must be closed explicitly).
+If a line starts with
+.BR '=' ,
+then
+.B lua
+displays the values of all the expressions in the remainder of the
+line. The expressions must be separated by commas.
+The primary prompt is the value of the global variable
+.BR _PROMPT ,
+if this value is a string;
+otherwise, the default prompt is used.
+Similarly, the secondary prompt is the value of the global variable
+.BR _PROMPT2 .
+So,
+to change the prompts,
+set the corresponding variable to a string of your choice.
+You can do that after calling the interpreter
+or on the command line
+(but in this case you have to be careful with quotes
+if the prompt string contains a space; otherwise you may confuse the shell.)
+The default prompts are "> " and ">> ".
+.SH OPTIONS
+.TP
+.B \-
+load and execute the standard input as a file,
+that is,
+not interactively,
+even when the standard input is a terminal.
+.TP
+.BI \-e " stat"
+execute statement
+.IR stat .
+You need to quote
+.I stat 
+if it contains spaces, quotes,
+or other characters special to the shell.
+.TP
+.B \-i
+enter interactive mode after
+.I script
+is executed.
+.TP
+.BI \-l " name"
+call
+.BI require(' name ')
+before executing
+.IR script .
+Typically used to load libraries.
+.TP
+.B \-v
+show version information.
+.SH "SEE ALSO"
+.BR luac (1)
+.br
+http://www.lua.org/
+.SH DIAGNOSTICS
+Error messages should be self explanatory.
+.SH AUTHORS
+R. Ierusalimschy,
+L. H. de Figueiredo,
+and
+W. Celes
+.\" EOF
diff --git a/com32/lua/doc/lua.css b/com32/lua/doc/lua.css
new file mode 100644
index 00000000..039cf116
--- /dev/null
+++ b/com32/lua/doc/lua.css
@@ -0,0 +1,41 @@
+body {
+	color: #000000 ;
+	background-color: #FFFFFF ;
+	font-family: sans-serif ;
+	text-align: justify ;
+	margin-right: 20px ;
+	margin-left: 20px ;
+}
+
+h1, h2, h3, h4 {
+	font-weight: normal ;
+	font-style: italic ;
+}
+
+a:link {
+	color: #000080 ;
+	background-color: inherit ;
+	text-decoration: none ;
+}
+
+a:visited {
+	background-color: inherit ;
+	text-decoration: none ;
+}
+
+a:link:hover, a:visited:hover {
+	color: #000080 ;
+	background-color: #E0E0FF ;
+}
+
+a:link:active, a:visited:active {
+	color: #FF0000 ;
+}
+
+hr {
+	border: 0 ;
+	height: 1px ;
+	color: #a0a0a0 ;
+	background-color: #a0a0a0 ;
+}
+
diff --git a/com32/lua/doc/lua.html b/com32/lua/doc/lua.html
new file mode 100644
index 00000000..1d435ab0
--- /dev/null
+++ b/com32/lua/doc/lua.html
@@ -0,0 +1,172 @@
+<!-- $Id: lua.man,v 1.11 2006/01/06 16:03:34 lhf Exp $ -->
+<HTML>
+<HEAD>
+<TITLE>LUA man page</TITLE>
+<LINK REL="stylesheet" TYPE="text/css" HREF="lua.css">
+</HEAD>
+
+<BODY BGCOLOR="#FFFFFF">
+
+<H2>NAME</H2>
+lua - Lua interpreter
+<H2>SYNOPSIS</H2>
+<B>lua</B>
+[
+<I>options</I>
+]
+[
+<I>script</I>
+[
+<I>args</I>
+]
+]
+<H2>DESCRIPTION</H2>
+<B>lua</B>
+is the stand-alone Lua interpreter.
+It loads and executes Lua programs,
+either in textual source form or
+in precompiled binary form.
+(Precompiled binaries are output by
+<B>luac</B>,
+the Lua compiler.)
+<B>lua</B>
+can be used as a batch interpreter and also interactively.
+<P>
+The given
+<I>options</I>
+(see below)
+are executed and then
+the Lua program in file
+<I>script</I>
+is loaded and executed.
+The given
+<I>args</I>
+are available to
+<I>script</I>
+as strings in a global table named
+<B>arg</B>.
+If these arguments contain spaces or other characters special to the shell,
+then they should be quoted
+(but note that the quotes will be removed by the shell).
+The arguments in
+<B>arg</B>
+start at 0,
+which contains the string
+'<I>script</I>'.
+The index of the last argument is stored in
+<B>arg.n</B>.
+The arguments given in the command line before
+<I>script</I>,
+including the name of the interpreter,
+are available in negative indices in
+<B>arg</B>.
+<P>
+At the very start,
+before even handling the command line,
+<B>lua</B>
+executes the contents of the environment variable
+<B>LUA_INIT</B>,
+if it is defined.
+If the value of
+<B>LUA_INIT</B>
+is of the form
+'@<I>filename</I>',
+then
+<I>filename</I>
+is executed.
+Otherwise, the string is assumed to be a Lua statement and is executed.
+<P>
+Options start with
+<B>'-'</B>
+and are described below.
+You can use
+<B>'--'</B>
+to signal the end of options.
+<P>
+If no arguments are given,
+then
+<B>"-v -i"</B>
+is assumed when the standard input is a terminal;
+otherwise,
+<B>"-"</B>
+is assumed.
+<P>
+In interactive mode,
+<B>lua</B>
+prompts the user,
+reads lines from the standard input,
+and executes them as they are read.
+If a line does not contain a complete statement,
+then a secondary prompt is displayed and
+lines are read until a complete statement is formed or
+a syntax error is found.
+So, one way to interrupt the reading of an incomplete statement is
+to force a syntax error:
+adding a
+<B>';'</B>
+in the middle of a statement is a sure way of forcing a syntax error
+(except inside multiline strings and comments; these must be closed explicitly).
+If a line starts with
+<B>'='</B>,
+then
+<B>lua</B>
+displays the values of all the expressions in the remainder of the
+line. The expressions must be separated by commas.
+The primary prompt is the value of the global variable
+<B>_PROMPT</B>,
+if this value is a string;
+otherwise, the default prompt is used.
+Similarly, the secondary prompt is the value of the global variable
+<B>_PROMPT2</B>.
+So,
+to change the prompts,
+set the corresponding variable to a string of your choice.
+You can do that after calling the interpreter
+or on the command line
+(but in this case you have to be careful with quotes
+if the prompt string contains a space; otherwise you may confuse the shell.)
+The default prompts are "&gt; " and "&gt;&gt; ".
+<H2>OPTIONS</H2>
+<P>
+<B>-</B>
+load and execute the standard input as a file,
+that is,
+not interactively,
+even when the standard input is a terminal.
+<P>
+<B>-e </B><I>stat</I>
+execute statement
+<I>stat</I>.
+You need to quote
+<I>stat </I>
+if it contains spaces, quotes,
+or other characters special to the shell.
+<P>
+<B>-i</B>
+enter interactive mode after
+<I>script</I>
+is executed.
+<P>
+<B>-l </B><I>name</I>
+call
+<B>require</B>('<I>name</I>')
+before executing
+<I>script</I>.
+Typically used to load libraries.
+<P>
+<B>-v</B>
+show version information.
+<H2>SEE ALSO</H2>
+<B>luac</B>(1)
+<BR>
+<A HREF="http://www.lua.org/">http://www.lua.org/</A>
+<H2>DIAGNOSTICS</H2>
+Error messages should be self explanatory.
+<H2>AUTHORS</H2>
+R. Ierusalimschy,
+L. H. de Figueiredo,
+and
+W. Celes
+<!-- EOF -->
+</BODY>
+</HTML>
diff --git a/com32/lua/doc/luac.1 b/com32/lua/doc/luac.1
new file mode 100644
index 00000000..d8146782
--- /dev/null
+++ b/com32/lua/doc/luac.1
@@ -0,0 +1,136 @@
+.\" $Id: luac.man,v 1.28 2006/01/06 16:03:34 lhf Exp $
+.TH LUAC 1 "$Date: 2006/01/06 16:03:34 $"
+.SH NAME
+luac \- Lua compiler
+.SH SYNOPSIS
+.B luac
+[
+.I options
+] [
+.I filenames
+]
+.SH DESCRIPTION
+.B luac
+is the Lua compiler.
+It translates programs written in the Lua programming language
+into binary files that can be later loaded and executed.
+.LP
+The main advantages of precompiling chunks are:
+faster loading,
+protecting source code from accidental user changes,
+and
+off-line syntax checking.
+.LP
+Pre-compiling does not imply faster execution
+because in Lua chunks are always compiled into bytecodes before being executed.
+.B luac
+simply allows those bytecodes to be saved in a file for later execution.
+.LP
+Pre-compiled chunks are not necessarily smaller than the corresponding source.
+The main goal in pre-compiling is faster loading.
+.LP
+The binary files created by
+.B luac
+are portable only among architectures with the same word size and byte order.
+.LP
+.B luac
+produces a single output file containing the bytecodes
+for all source files given.
+By default,
+the output file is named
+.BR luac.out ,
+but you can change this with the
+.B \-o
+option.
+.LP
+In the command line,
+you can mix
+text files containing Lua source and
+binary files containing precompiled chunks.
+This is useful to combine several precompiled chunks,
+even from different (but compatible) platforms,
+into a single precompiled chunk.
+.LP
+You can use
+.B "'\-'"
+to indicate the standard input as a source file
+and
+.B "'\--'"
+to signal the end of options
+(that is,
+all remaining arguments will be treated as files even if they start with
+.BR "'\-'" ).
+.LP
+The internal format of the binary files produced by
+.B luac
+is likely to change when a new version of Lua is released.
+So,
+save the source files of all Lua programs that you precompile.
+.LP
+.SH OPTIONS
+Options must be separate.
+.TP
+.B \-l
+produce a listing of the compiled bytecode for Lua's virtual machine.
+Listing bytecodes is useful to learn about Lua's virtual machine.
+If no files are given, then
+.B luac
+loads
+.B luac.out
+and lists its contents.
+.TP
+.BI \-o " file"
+output to
+.IR file ,
+instead of the default
+.BR luac.out .
+(You can use
+.B "'\-'"
+for standard output,
+but not on platforms that open standard output in text mode.)
+The output file may be a source file because
+all files are loaded before the output file is written.
+Be careful not to overwrite precious files.
+.TP
+.B \-p
+load files but do not generate any output file.
+Used mainly for syntax checking and for testing precompiled chunks:
+corrupted files will probably generate errors when loaded.
+Lua always performs a thorough integrity test on precompiled chunks.
+Bytecode that passes this test is completely safe,
+in the sense that it will not break the interpreter.
+However,
+there is no guarantee that such code does anything sensible.
+(None can be given, because the halting problem is unsolvable.)
+If no files are given, then
+.B luac
+loads
+.B luac.out
+and tests its contents.
+No messages are displayed if the file passes the integrity test.
+.TP
+.B \-s
+strip debug information before writing the output file.
+This saves some space in very large chunks,
+but if errors occur when running a stripped chunk,
+then the error messages may not contain the full information they usually do.
+For instance,
+line numbers and names of local variables are lost.
+.TP
+.B \-v
+show version information.
+.SH FILES
+.TP 15
+.B luac.out
+default output file
+.SH "SEE ALSO"
+.BR lua (1)
+.br
+http://www.lua.org/
+.SH DIAGNOSTICS
+Error messages should be self explanatory.
+.SH AUTHORS
+L. H. de Figueiredo,
+R. Ierusalimschy and
+W. Celes
+.\" EOF
diff --git a/com32/lua/doc/luac.html b/com32/lua/doc/luac.html
new file mode 100644
index 00000000..179ffe82
--- /dev/null
+++ b/com32/lua/doc/luac.html
@@ -0,0 +1,145 @@
+<!-- $Id: luac.man,v 1.28 2006/01/06 16:03:34 lhf Exp $ -->
+<HTML>
+<HEAD>
+<TITLE>LUAC man page</TITLE>
+<LINK REL="stylesheet" TYPE="text/css" HREF="lua.css">
+</HEAD>
+
+<BODY BGCOLOR="#FFFFFF">
+
+<H2>NAME</H2>
+luac - Lua compiler
+<H2>SYNOPSIS</H2>
+<B>luac</B>
+[
+<I>options</I>
+] [
+<I>filenames</I>
+]
+<H2>DESCRIPTION</H2>
+<B>luac</B>
+is the Lua compiler.
+It translates programs written in the Lua programming language
+into binary files that can be later loaded and executed.
+<P>
+The main advantages of precompiling chunks are:
+faster loading,
+protecting source code from accidental user changes,
+and
+off-line syntax checking.
+<P>
+Precompiling does not imply faster execution
+because in Lua chunks are always compiled into bytecodes before being executed.
+<B>luac</B>
+simply allows those bytecodes to be saved in a file for later execution.
+<P>
+Precompiled chunks are not necessarily smaller than the corresponding source.
+The main goal in precompiling is faster loading.
+<P>
+The binary files created by
+<B>luac</B>
+are portable only among architectures with the same word size and byte order.
+<P>
+<B>luac</B>
+produces a single output file containing the bytecodes
+for all source files given.
+By default,
+the output file is named
+<B>luac.out</B>,
+but you can change this with the
+<B>-o</B>
+option.
+<P>
+In the command line,
+you can mix
+text files containing Lua source and
+binary files containing precompiled chunks.
+This is useful because several precompiled chunks,
+even from different (but compatible) platforms,
+can be combined into a single precompiled chunk.
+<P>
+You can use
+<B>'-'</B>
+to indicate the standard input as a source file
+and
+<B>'--'</B>
+to signal the end of options
+(that is,
+all remaining arguments will be treated as files even if they start with
+<B>'-'</B>).
+<P>
+The internal format of the binary files produced by
+<B>luac</B>
+is likely to change when a new version of Lua is released.
+So,
+save the source files of all Lua programs that you precompile.
+<P>
+<H2>OPTIONS</H2>
+Options must be separate.
+<P>
+<B>-l</B>
+produce a listing of the compiled bytecode for Lua's virtual machine.
+Listing bytecodes is useful to learn about Lua's virtual machine.
+If no files are given, then
+<B>luac</B>
+loads
+<B>luac.out</B>
+and lists its contents.
+<P>
+<B>-o </B><I>file</I>
+output to
+<I>file</I>,
+instead of the default
+<B>luac.out</B>.
+(You can use
+<B>'-'</B>
+for standard output,
+but not on platforms that open standard output in text mode.)
+The output file may be a source file because
+all files are loaded before the output file is written.
+Be careful not to overwrite precious files.
+<P>
+<B>-p</B>
+load files but do not generate any output file.
+Used mainly for syntax checking and for testing precompiled chunks:
+corrupted files will probably generate errors when loaded.
+Lua always performs a thorough integrity test on precompiled chunks.
+Bytecode that passes this test is completely safe,
+in the sense that it will not break the interpreter.
+However,
+there is no guarantee that such code does anything sensible.
+(None can be given, because the halting problem is unsolvable.)
+If no files are given, then
+<B>luac</B>
+loads
+<B>luac.out</B>
+and tests its contents.
+No messages are displayed if the file passes the integrity test.
+<P>
+<B>-s</B>
+strip debug information before writing the output file.
+This saves some space in very large chunks,
+but if errors occur when running a stripped chunk,
+then the error messages may not contain the full information they usually do.
+For instance,
+line numbers and names of local variables are lost.
+<P>
+<B>-v</B>
+show version information.
+<H2>FILES</H2>
+<P>
+<B>luac.out</B>
+default output file
+<H2>SEE ALSO</H2>
+<B>lua</B>(1)
+<BR>
+<A HREF="http://www.lua.org/">http://www.lua.org/</A>
+<H2>DIAGNOSTICS</H2>
+Error messages should be self explanatory.
+<H2>AUTHORS</H2>
+L. H. de Figueiredo,
+R. Ierusalimschy and
+W. Celes
+<!-- EOF -->
+</BODY>
+</HTML>
diff --git a/com32/lua/doc/manual.css b/com32/lua/doc/manual.css
new file mode 100644
index 00000000..eed5afd9
--- /dev/null
+++ b/com32/lua/doc/manual.css
@@ -0,0 +1,13 @@
+h3 code {
+	font-family: inherit ;
+}
+
+pre {
+	font-size: 105% ;
+}
+
+span.apii {
+	float: right ;
+	font-family: inherit ;
+}
+
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+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
+<html>
+
+<head>
+<title>Lua 5.1 Reference Manual</title>
+<link rel="stylesheet" href="lua.css">
+<link rel="stylesheet" href="manual.css">
+<META HTTP-EQUIV="content-type" CONTENT="text/html; charset=iso-8859-1">
+</head>
+
+<body>
+
+<hr>
+<h1>
+<a href="http://www.lua.org/"><img src="logo.gif" alt="" border="0"></a>
+Lua 5.1 Reference Manual
+</h1>
+
+by Roberto Ierusalimschy, Luiz Henrique de Figueiredo, Waldemar Celes
+<p>
+<small>
+Copyright &copy; 2006-2008 Lua.org, PUC-Rio.
+Freely available under the terms of the
+<a href="http://www.lua.org/license.html#5">Lua license</a>.
+</small>
+<hr>
+<p>
+
+<a href="contents.html#contents">contents</A>
+&middot;
+<a href="contents.html#index">index</A>
+
+<!-- ====================================================================== -->
+<p>
+
+<!-- $Id: manual.of,v 1.45 2008/01/19 00:17:30 roberto Exp $ -->
+
+
+
+
+<h1>1 - <a name="1">Introduction</a></h1>
+
+<p>
+Lua is an extension programming language designed to support
+general procedural programming with data description
+facilities.
+It also offers good support for object-oriented programming,
+functional programming, and data-driven programming.
+Lua is intended to be used as a powerful, light-weight
+scripting language for any program that needs one.
+Lua is implemented as a library, written in <em>clean</em> C
+(that is, in the common subset of ANSI&nbsp;C and C++).
+
+
+<p>
+Being an extension language, Lua has no notion of a "main" program:
+it only works <em>embedded</em> in a host client,
+called the <em>embedding program</em> or simply the <em>host</em>.
+This host program can invoke functions to execute a piece of Lua code,
+can write and read Lua variables,
+and can register C&nbsp;functions to be called by Lua code.
+Through the use of C&nbsp;functions, Lua can be augmented to cope with
+a wide range of different domains,
+thus creating customized programming languages sharing a syntactical framework.
+The Lua distribution includes a sample host program called <code>lua</code>,
+which uses the Lua library to offer a complete, stand-alone Lua interpreter.
+
+
+<p>
+Lua is free software,
+and is provided as usual with no guarantees,
+as stated in its license.
+The implementation described in this manual is available
+at Lua's official web site, <code>www.lua.org</code>.
+
+
+<p>
+Like any other reference manual,
+this document is dry in places.
+For a discussion of the decisions behind the design of Lua,
+see the technical papers available at Lua's web site.
+For a detailed introduction to programming in Lua,
+see Roberto's book, <em>Programming in Lua (Second Edition)</em>.
+
+
+
+<h1>2 - <a name="2">The Language</a></h1>
+
+<p>
+This section describes the lexis, the syntax, and the semantics of Lua.
+In other words,
+this section describes
+which tokens are valid,
+how they can be combined,
+and what their combinations mean.
+
+
+<p>
+The language constructs will be explained using the usual extended BNF notation,
+in which
+{<em>a</em>}&nbsp;means&nbsp;0 or more <em>a</em>'s, and
+[<em>a</em>]&nbsp;means an optional <em>a</em>.
+Non-terminals are shown like non-terminal,
+keywords are shown like <b>kword</b>,
+and other terminal symbols are shown like `<b>=</b>&acute;.
+The complete syntax of Lua can be found at the end of this manual.
+
+
+
+<h2>2.1 - <a name="2.1">Lexical Conventions</a></h2>
+
+<p>
+<em>Names</em>
+(also called <em>identifiers</em>)
+in Lua can be any string of letters,
+digits, and underscores,
+not beginning with a digit.
+This coincides with the definition of names in most languages.
+(The definition of letter depends on the current locale:
+any character considered alphabetic by the current locale
+can be used in an identifier.)
+Identifiers are used to name variables and table fields.
+
+
+<p>
+The following <em>keywords</em> are reserved
+and cannot be used as names:
+
+
+<pre>
+     and       break     do        else      elseif
+     end       false     for       function  if
+     in        local     nil       not       or
+     repeat    return    then      true      until     while
+</pre>
+
+<p>
+Lua is a case-sensitive language:
+<code>and</code> is a reserved word, but <code>And</code> and <code>AND</code>
+are two different, valid names.
+As a convention, names starting with an underscore followed by
+uppercase letters (such as <code>_VERSION</code>)
+are reserved for internal global variables used by Lua.
+
+
+<p>
+The following strings denote other tokens:
+
+<pre>
+     +     -     *     /     %     ^     #
+     ==    ~=    &lt;=    &gt;=    &lt;     &gt;     =
+     (     )     {     }     [     ]
+     ;     :     ,     .     ..    ...
+</pre>
+
+<p>
+<em>Literal strings</em>
+can be delimited by matching single or double quotes,
+and can contain the following C-like escape sequences:
+'<code>\a</code>' (bell),
+'<code>\b</code>' (backspace),
+'<code>\f</code>' (form feed),
+'<code>\n</code>' (newline),
+'<code>\r</code>' (carriage return),
+'<code>\t</code>' (horizontal tab),
+'<code>\v</code>' (vertical tab),
+'<code>\\</code>' (backslash),
+'<code>\"</code>' (quotation mark [double quote]),
+and '<code>\'</code>' (apostrophe [single quote]).
+Moreover, a backslash followed by a real newline
+results in a newline in the string.
+A character in a string may also be specified by its numerical value
+using the escape sequence <code>\<em>ddd</em></code>,
+where <em>ddd</em> is a sequence of up to three decimal digits.
+(Note that if a numerical escape is to be followed by a digit,
+it must be expressed using exactly three digits.)
+Strings in Lua may contain any 8-bit value, including embedded zeros,
+which can be specified as '<code>\0</code>'.
+
+
+<p>
+To put a double (single) quote, a newline, a backslash,
+a carriage return,
+or an embedded zero
+inside a literal string enclosed by double (single) quotes
+you must use an escape sequence.
+Any other character may be directly inserted into the literal.
+(Some control characters may cause problems for the file system,
+but Lua has no problem with them.)
+
+
+<p>
+Literal strings can also be defined using a long format
+enclosed by <em>long brackets</em>.
+We define an <em>opening long bracket of level <em>n</em></em> as an opening
+square bracket followed by <em>n</em> equal signs followed by another
+opening square bracket.
+So, an opening long bracket of level&nbsp;0 is written as <code>[[</code>,
+an opening long bracket of level&nbsp;1 is written as <code>[=[</code>,
+and so on.
+A <em>closing long bracket</em> is defined similarly;
+for instance, a closing long bracket of level&nbsp;4 is written as <code>]====]</code>.
+A long string starts with an opening long bracket of any level and
+ends at the first closing long bracket of the same level.
+Literals in this bracketed form may run for several lines,
+do not interpret any escape sequences,
+and ignore long brackets of any other level.
+They may contain anything except a closing bracket of the proper level.
+
+
+<p>
+For convenience,
+when the opening long bracket is immediately followed by a newline,
+the newline is not included in the string.
+As an example, in a system using ASCII
+(in which '<code>a</code>' is coded as&nbsp;97,
+newline is coded as&nbsp;10, and '<code>1</code>' is coded as&nbsp;49),
+the five literals below denote the same string:
+
+<pre>
+     a = 'alo\n123"'
+     a = "alo\n123\""
+     a = '\97lo\10\04923"'
+     a = [[alo
+     123"]]
+     a = [==[
+     alo
+     123"]==]
+</pre>
+
+<p>
+A <em>numerical constant</em> may be written with an optional decimal part
+and an optional decimal exponent.
+Lua also accepts integer hexadecimal constants,
+by prefixing them with <code>0x</code>.
+Examples of valid numerical constants are
+
+<pre>
+     3   3.0   3.1416   314.16e-2   0.31416E1   0xff   0x56
+</pre>
+
+<p>
+A <em>comment</em> starts with a double hyphen (<code>--</code>)
+anywhere outside a string.
+If the text immediately after <code>--</code> is not an opening long bracket,
+the comment is a <em>short comment</em>,
+which runs until the end of the line.
+Otherwise, it is a <em>long comment</em>,
+which runs until the corresponding closing long bracket.
+Long comments are frequently used to disable code temporarily.
+
+
+
+
+
+<h2>2.2 - <a name="2.2">Values and Types</a></h2>
+
+<p>
+Lua is a <em>dynamically typed language</em>.
+This means that
+variables do not have types; only values do.
+There are no type definitions in the language.
+All values carry their own type.
+
+
+<p>
+All values in Lua are <em>first-class values</em>.
+This means that all values can be stored in variables,
+passed as arguments to other functions, and returned as results.
+
+
+<p>
+There are eight basic types in Lua:
+<em>nil</em>, <em>boolean</em>, <em>number</em>,
+<em>string</em>, <em>function</em>, <em>userdata</em>,
+<em>thread</em>, and <em>table</em>.
+<em>Nil</em> is the type of the value <b>nil</b>,
+whose main property is to be different from any other value;
+it usually represents the absence of a useful value.
+<em>Boolean</em> is the type of the values <b>false</b> and <b>true</b>.
+Both <b>nil</b> and <b>false</b> make a condition false;
+any other value makes it true.
+<em>Number</em> represents real (double-precision floating-point) numbers.
+(It is easy to build Lua interpreters that use other
+internal representations for numbers,
+such as single-precision float or long integers;
+see file <code>luaconf.h</code>.)
+<em>String</em> represents arrays of characters.
+
+Lua is 8-bit clean:
+strings may contain any 8-bit character,
+including embedded zeros ('<code>\0</code>') (see <a href="#2.1">&sect;2.1</a>).
+
+
+<p>
+Lua can call (and manipulate) functions written in Lua and
+functions written in C
+(see <a href="#2.5.8">&sect;2.5.8</a>).
+
+
+<p>
+The type <em>userdata</em> is provided to allow arbitrary C&nbsp;data to
+be stored in Lua variables.
+This type corresponds to a block of raw memory
+and has no pre-defined operations in Lua,
+except assignment and identity test.
+However, by using <em>metatables</em>,
+the programmer can define operations for userdata values
+(see <a href="#2.8">&sect;2.8</a>).
+Userdata values cannot be created or modified in Lua,
+only through the C&nbsp;API.
+This guarantees the integrity of data owned by the host program.
+
+
+<p>
+The type <em>thread</em> represents independent threads of execution
+and it is used to implement coroutines (see <a href="#2.11">&sect;2.11</a>).
+Do not confuse Lua threads with operating-system threads.
+Lua supports coroutines on all systems,
+even those that do not support threads.
+
+
+<p>
+The type <em>table</em> implements associative arrays,
+that is, arrays that can be indexed not only with numbers,
+but with any value (except <b>nil</b>).
+Tables can be <em>heterogeneous</em>;
+that is, they can contain values of all types (except <b>nil</b>).
+Tables are the sole data structuring mechanism in Lua;
+they may be used to represent ordinary arrays,
+symbol tables, sets, records, graphs, trees, etc.
+To represent records, Lua uses the field name as an index.
+The language supports this representation by
+providing <code>a.name</code> as syntactic sugar for <code>a["name"]</code>.
+There are several convenient ways to create tables in Lua
+(see <a href="#2.5.7">&sect;2.5.7</a>).
+
+
+<p>
+Like indices,
+the value of a table field can be of any type (except <b>nil</b>).
+In particular,
+because functions are first-class values,
+table fields may contain functions.
+Thus tables may also carry <em>methods</em> (see <a href="#2.5.9">&sect;2.5.9</a>).
+
+
+<p>
+Tables, functions, threads, and (full) userdata values are <em>objects</em>:
+variables do not actually <em>contain</em> these values,
+only <em>references</em> to them.
+Assignment, parameter passing, and function returns
+always manipulate references to such values;
+these operations do not imply any kind of copy.
+
+
+<p>
+The library function <a href="#pdf-type"><code>type</code></a> returns a string describing the type
+of a given value.
+
+
+
+<h3>2.2.1 - <a name="2.2.1">Coercion</a></h3>
+
+<p>
+Lua provides automatic conversion between
+string and number values at run time.
+Any arithmetic operation applied to a string tries to convert
+this string to a number, following the usual conversion rules.
+Conversely, whenever a number is used where a string is expected,
+the number is converted to a string, in a reasonable format.
+For complete control over how numbers are converted to strings,
+use the <code>format</code> function from the string library
+(see <a href="#pdf-string.format"><code>string.format</code></a>).
+
+
+
+
+
+
+
+<h2>2.3 - <a name="2.3">Variables</a></h2>
+
+<p>
+Variables are places that store values.
+
+There are three kinds of variables in Lua:
+global variables, local variables, and table fields.
+
+
+<p>
+A single name can denote a global variable or a local variable
+(or a function's formal parameter,
+which is a particular kind of local variable):
+
+<pre>
+	var ::= Name
+</pre><p>
+Name denotes identifiers, as defined in <a href="#2.1">&sect;2.1</a>.
+
+
+<p>
+Any variable is assumed to be global unless explicitly declared
+as a local (see <a href="#2.4.7">&sect;2.4.7</a>).
+Local variables are <em>lexically scoped</em>:
+local variables can be freely accessed by functions
+defined inside their scope (see <a href="#2.6">&sect;2.6</a>).
+
+
+<p>
+Before the first assignment to a variable, its value is <b>nil</b>.
+
+
+<p>
+Square brackets are used to index a table:
+
+<pre>
+	var ::= prefixexp `<b>[</b>&acute; exp `<b>]</b>&acute;
+</pre><p>
+The meaning of accesses to global variables 
+and table fields can be changed via metatables.
+An access to an indexed variable <code>t[i]</code> is equivalent to
+a call <code>gettable_event(t,i)</code>.
+(See <a href="#2.8">&sect;2.8</a> for a complete description of the
+<code>gettable_event</code> function.
+This function is not defined or callable in Lua.
+We use it here only for explanatory purposes.)
+
+
+<p>
+The syntax <code>var.Name</code> is just syntactic sugar for
+<code>var["Name"]</code>:
+
+<pre>
+	var ::= prefixexp `<b>.</b>&acute; Name
+</pre>
+
+<p>
+All global variables live as fields in ordinary Lua tables,
+called <em>environment tables</em> or simply
+<em>environments</em> (see <a href="#2.9">&sect;2.9</a>).
+Each function has its own reference to an environment,
+so that all global variables in this function
+will refer to this environment table.
+When a function is created,
+it inherits the environment from the function that created it.
+To get the environment table of a Lua function,
+you call <a href="#pdf-getfenv"><code>getfenv</code></a>.
+To replace it,
+you call <a href="#pdf-setfenv"><code>setfenv</code></a>.
+(You can only manipulate the environment of C&nbsp;functions
+through the debug library; (see <a href="#5.9">&sect;5.9</a>).)
+
+
+<p>
+An access to a global variable <code>x</code>
+is equivalent to <code>_env.x</code>,
+which in turn is equivalent to
+
+<pre>
+     gettable_event(_env, "x")
+</pre><p>
+where <code>_env</code> is the environment of the running function.
+(See <a href="#2.8">&sect;2.8</a> for a complete description of the
+<code>gettable_event</code> function.
+This function is not defined or callable in Lua.
+Similarly, the <code>_env</code> variable is not defined in Lua.
+We use them here only for explanatory purposes.)
+
+
+
+
+
+<h2>2.4 - <a name="2.4">Statements</a></h2>
+
+<p>
+Lua supports an almost conventional set of statements,
+similar to those in Pascal or C.
+This set includes
+assignment, control structures, function calls,
+and variable declarations.
+
+
+
+<h3>2.4.1 - <a name="2.4.1">Chunks</a></h3>
+
+<p>
+The unit of execution of Lua is called a <em>chunk</em>.
+A chunk is simply a sequence of statements,
+which are executed sequentially.
+Each statement can be optionally followed by a semicolon:
+
+<pre>
+	chunk ::= {stat [`<b>;</b>&acute;]}
+</pre><p>
+There are no empty statements and thus '<code>;;</code>' is not legal.
+
+
+<p>
+Lua handles a chunk as the body of an anonymous function 
+with a variable number of arguments
+(see <a href="#2.5.9">&sect;2.5.9</a>).
+As such, chunks can define local variables,
+receive arguments, and return values.
+
+
+<p>
+A chunk may be stored in a file or in a string inside the host program.
+When a chunk is executed, first it is pre-compiled into instructions for
+a virtual machine,
+and then the compiled code is executed
+by an interpreter for the virtual machine.
+
+
+<p>
+Chunks may also be pre-compiled into binary form;
+see program <code>luac</code> for details.
+Programs in source and compiled forms are interchangeable;
+Lua automatically detects the file type and acts accordingly.
+
+
+
+
+
+
+<h3>2.4.2 - <a name="2.4.2">Blocks</a></h3><p>
+A block is a list of statements;
+syntactically, a block is the same as a chunk:
+
+<pre>
+	block ::= chunk
+</pre>
+
+<p>
+A block may be explicitly delimited to produce a single statement:
+
+<pre>
+	stat ::= <b>do</b> block <b>end</b>
+</pre><p>
+Explicit blocks are useful
+to control the scope of variable declarations.
+Explicit blocks are also sometimes used to
+add a <b>return</b> or <b>break</b> statement in the middle
+of another block (see <a href="#2.4.4">&sect;2.4.4</a>).
+
+
+
+
+
+<h3>2.4.3 - <a name="2.4.3">Assignment</a></h3>
+
+<p>
+Lua allows multiple assignment.
+Therefore, the syntax for assignment
+defines a list of variables on the left side
+and a list of expressions on the right side.
+The elements in both lists are separated by commas:
+
+<pre>
+	stat ::= varlist `<b>=</b>&acute; explist
+	varlist ::= var {`<b>,</b>&acute; var}
+	explist ::= exp {`<b>,</b>&acute; exp}
+</pre><p>
+Expressions are discussed in <a href="#2.5">&sect;2.5</a>.
+
+
+<p>
+Before the assignment,
+the list of values is <em>adjusted</em> to the length of
+the list of variables.
+If there are more values than needed,
+the excess values are thrown away.
+If there are fewer values than needed,
+the list is extended with as many  <b>nil</b>'s as needed.
+If the list of expressions ends with a function call,
+then all values returned by this call enter in the list of values,
+before the adjustment
+(except when the call is enclosed in parentheses; see <a href="#2.5">&sect;2.5</a>).
+
+
+<p>
+The assignment statement first evaluates all its expressions
+and only then are the assignments performed.
+Thus the code
+
+<pre>
+     i = 3
+     i, a[i] = i+1, 20
+</pre><p>
+sets <code>a[3]</code> to 20, without affecting <code>a[4]</code>
+because the <code>i</code> in <code>a[i]</code> is evaluated (to 3)
+before it is assigned&nbsp;4.
+Similarly, the line
+
+<pre>
+     x, y = y, x
+</pre><p>
+exchanges the values of <code>x</code> and <code>y</code>.
+
+
+<p>
+The meaning of assignments to global variables
+and table fields can be changed via metatables.
+An assignment to an indexed variable <code>t[i] = val</code> is equivalent to
+<code>settable_event(t,i,val)</code>.
+(See <a href="#2.8">&sect;2.8</a> for a complete description of the
+<code>settable_event</code> function.
+This function is not defined or callable in Lua.
+We use it here only for explanatory purposes.)
+
+
+<p>
+An assignment to a global variable <code>x = val</code>
+is equivalent to the assignment
+<code>_env.x = val</code>,
+which in turn is equivalent to
+
+<pre>
+     settable_event(_env, "x", val)
+</pre><p>
+where <code>_env</code> is the environment of the running function.
+(The <code>_env</code> variable is not defined in Lua.
+We use it here only for explanatory purposes.)
+
+
+
+
+
+<h3>2.4.4 - <a name="2.4.4">Control Structures</a></h3><p>
+The control structures
+<b>if</b>, <b>while</b>, and <b>repeat</b> have the usual meaning and
+familiar syntax:
+
+
+
+
+<pre>
+	stat ::= <b>while</b> exp <b>do</b> block <b>end</b>
+	stat ::= <b>repeat</b> block <b>until</b> exp
+	stat ::= <b>if</b> exp <b>then</b> block {<b>elseif</b> exp <b>then</b> block} [<b>else</b> block] <b>end</b>
+</pre><p>
+Lua also has a <b>for</b> statement, in two flavors (see <a href="#2.4.5">&sect;2.4.5</a>).
+
+
+<p>
+The condition expression of a
+control structure may return any value.
+Both <b>false</b> and <b>nil</b> are considered false.
+All values different from <b>nil</b> and <b>false</b> are considered true
+(in particular, the number 0 and the empty string are also true).
+
+
+<p>
+In the <b>repeat</b>&ndash;<b>until</b> loop,
+the inner block does not end at the <b>until</b> keyword,
+but only after the condition.
+So, the condition can refer to local variables
+declared inside the loop block.
+
+
+<p>
+The <b>return</b> statement is used to return values
+from a function or a chunk (which is just a function).
+
+Functions and chunks may return more than one value,
+so the syntax for the <b>return</b> statement is
+
+<pre>
+	stat ::= <b>return</b> [explist]
+</pre>
+
+<p>
+The <b>break</b> statement is used to terminate the execution of a
+<b>while</b>, <b>repeat</b>, or <b>for</b> loop,
+skipping to the next statement after the loop:
+
+
+<pre>
+	stat ::= <b>break</b>
+</pre><p>
+A <b>break</b> ends the innermost enclosing loop.
+
+
+<p>
+The <b>return</b> and <b>break</b>
+statements can only be written as the <em>last</em> statement of a block.
+If it is really necessary to <b>return</b> or <b>break</b> in the
+middle of a block,
+then an explicit inner block can be used,
+as in the idioms
+<code>do return end</code> and <code>do break end</code>,
+because now <b>return</b> and <b>break</b> are the last statements in
+their (inner) blocks.
+
+
+
+
+
+<h3>2.4.5 - <a name="2.4.5">For Statement</a></h3>
+
+<p>
+
+The <b>for</b> statement has two forms:
+one numeric and one generic.
+
+
+<p>
+The numeric <b>for</b> loop repeats a block of code while a
+control variable runs through an arithmetic progression.
+It has the following syntax:
+
+<pre>
+	stat ::= <b>for</b> Name `<b>=</b>&acute; exp `<b>,</b>&acute; exp [`<b>,</b>&acute; exp] <b>do</b> block <b>end</b>
+</pre><p>
+The <em>block</em> is repeated for <em>name</em> starting at the value of
+the first <em>exp</em>, until it passes the second <em>exp</em> by steps of the
+third <em>exp</em>.
+More precisely, a <b>for</b> statement like
+
+<pre>
+     for v = <em>e1</em>, <em>e2</em>, <em>e3</em> do <em>block</em> end
+</pre><p>
+is equivalent to the code:
+
+<pre>
+     do
+       local <em>var</em>, <em>limit</em>, <em>step</em> = tonumber(<em>e1</em>), tonumber(<em>e2</em>), tonumber(<em>e3</em>)
+       if not (<em>var</em> and <em>limit</em> and <em>step</em>) then error() end
+       while (<em>step</em> &gt; 0 and <em>var</em> &lt;= <em>limit</em>) or (<em>step</em> &lt;= 0 and <em>var</em> &gt;= <em>limit</em>) do
+         local v = <em>var</em>
+         <em>block</em>
+         <em>var</em> = <em>var</em> + <em>step</em>
+       end
+     end
+</pre><p>
+Note the following:
+
+<ul>
+
+<li>
+All three control expressions are evaluated only once,
+before the loop starts.
+They must all result in numbers.
+</li>
+
+<li>
+<code><em>var</em></code>, <code><em>limit</em></code>, and <code><em>step</em></code> are invisible variables.
+The names are here for explanatory purposes only.
+</li>
+
+<li>
+If the third expression (the step) is absent,
+then a step of&nbsp;1 is used.
+</li>
+
+<li>
+You can use <b>break</b> to exit a <b>for</b> loop.
+</li>
+
+<li>
+The loop variable <code>v</code> is local to the loop;
+you cannot use its value after the <b>for</b> ends or is broken.
+If you need this value,
+assign it to another variable before breaking or exiting the loop.
+</li>
+
+</ul>
+
+<p>
+The generic <b>for</b> statement works over functions,
+called <em>iterators</em>.
+On each iteration, the iterator function is called to produce a new value,
+stopping when this new value is <b>nil</b>.
+The generic <b>for</b> loop has the following syntax:
+
+<pre>
+	stat ::= <b>for</b> namelist <b>in</b> explist <b>do</b> block <b>end</b>
+	namelist ::= Name {`<b>,</b>&acute; Name}
+</pre><p>
+A <b>for</b> statement like
+
+<pre>
+     for <em>var_1</em>, &middot;&middot;&middot;, <em>var_n</em> in <em>explist</em> do <em>block</em> end
+</pre><p>
+is equivalent to the code:
+
+<pre>
+     do
+       local <em>f</em>, <em>s</em>, <em>var</em> = <em>explist</em>
+       while true do
+         local <em>var_1</em>, &middot;&middot;&middot;, <em>var_n</em> = <em>f</em>(<em>s</em>, <em>var</em>)
+         <em>var</em> = <em>var_1</em>
+         if <em>var</em> == nil then break end
+         <em>block</em>
+       end
+     end
+</pre><p>
+Note the following:
+
+<ul>
+
+<li>
+<code><em>explist</em></code> is evaluated only once.
+Its results are an <em>iterator</em> function,
+a <em>state</em>,
+and an initial value for the first <em>iterator variable</em>.
+</li>
+
+<li>
+<code><em>f</em></code>, <code><em>s</em></code>, and <code><em>var</em></code> are invisible variables.
+The names are here for explanatory purposes only.
+</li>
+
+<li>
+You can use <b>break</b> to exit a <b>for</b> loop.
+</li>
+
+<li>
+The loop variables <code><em>var_i</em></code> are local to the loop;
+you cannot use their values after the <b>for</b> ends.
+If you need these values,
+then assign them to other variables before breaking or exiting the loop.
+</li>
+
+</ul>
+
+
+
+
+<h3>2.4.6 - <a name="2.4.6">Function Calls as Statements</a></h3><p>
+To allow possible side-effects,
+function calls can be executed as statements:
+
+<pre>
+	stat ::= functioncall
+</pre><p>
+In this case, all returned values are thrown away.
+Function calls are explained in <a href="#2.5.8">&sect;2.5.8</a>.
+
+
+
+
+
+<h3>2.4.7 - <a name="2.4.7">Local Declarations</a></h3><p>
+Local variables may be declared anywhere inside a block.
+The declaration may include an initial assignment:
+
+<pre>
+	stat ::= <b>local</b> namelist [`<b>=</b>&acute; explist]
+</pre><p>
+If present, an initial assignment has the same semantics
+of a multiple assignment (see <a href="#2.4.3">&sect;2.4.3</a>).
+Otherwise, all variables are initialized with <b>nil</b>.
+
+
+<p>
+A chunk is also a block (see <a href="#2.4.1">&sect;2.4.1</a>),
+and so local variables can be declared in a chunk outside any explicit block.
+The scope of such local variables extends until the end of the chunk.
+
+
+<p>
+The visibility rules for local variables are explained in <a href="#2.6">&sect;2.6</a>.
+
+
+
+
+
+
+
+<h2>2.5 - <a name="2.5">Expressions</a></h2>
+
+<p>
+The basic expressions in Lua are the following:
+
+<pre>
+	exp ::= prefixexp
+	exp ::= <b>nil</b> | <b>false</b> | <b>true</b>
+	exp ::= Number
+	exp ::= String
+	exp ::= function
+	exp ::= tableconstructor
+	exp ::= `<b>...</b>&acute;
+	exp ::= exp binop exp
+	exp ::= unop exp
+	prefixexp ::= var | functioncall | `<b>(</b>&acute; exp `<b>)</b>&acute;
+</pre>
+
+<p>
+Numbers and literal strings are explained in <a href="#2.1">&sect;2.1</a>;
+variables are explained in <a href="#2.3">&sect;2.3</a>;
+function definitions are explained in <a href="#2.5.9">&sect;2.5.9</a>;
+function calls are explained in <a href="#2.5.8">&sect;2.5.8</a>;
+table constructors are explained in <a href="#2.5.7">&sect;2.5.7</a>.
+Vararg expressions,
+denoted by three dots ('<code>...</code>'), can only be used when
+directly inside a vararg function;
+they are explained in <a href="#2.5.9">&sect;2.5.9</a>.
+
+
+<p>
+Binary operators comprise arithmetic operators (see <a href="#2.5.1">&sect;2.5.1</a>),
+relational operators (see <a href="#2.5.2">&sect;2.5.2</a>), logical operators (see <a href="#2.5.3">&sect;2.5.3</a>),
+and the concatenation operator (see <a href="#2.5.4">&sect;2.5.4</a>).
+Unary operators comprise the unary minus (see <a href="#2.5.1">&sect;2.5.1</a>),
+the unary <b>not</b> (see <a href="#2.5.3">&sect;2.5.3</a>),
+and the unary <em>length operator</em> (see <a href="#2.5.5">&sect;2.5.5</a>).
+
+
+<p>
+Both function calls and vararg expressions may result in multiple values.
+If the expression is used as a statement (see <a href="#2.4.6">&sect;2.4.6</a>)
+(only possible for function calls),
+then its return list is adjusted to zero elements,
+thus discarding all returned values.
+If the expression is used as the last (or the only) element
+of a list of expressions,
+then no adjustment is made
+(unless the call is enclosed in parentheses).
+In all other contexts,
+Lua adjusts the result list to one element,
+discarding all values except the first one.
+
+
+<p>
+Here are some examples:
+
+<pre>
+     f()                -- adjusted to 0 results
+     g(f(), x)          -- f() is adjusted to 1 result
+     g(x, f())          -- g gets x plus all results from f()
+     a,b,c = f(), x     -- f() is adjusted to 1 result (c gets nil)
+     a,b = ...          -- a gets the first vararg parameter, b gets
+                        -- the second (both a and b may get nil if there
+                        -- is no corresponding vararg parameter)
+     
+     a,b,c = x, f()     -- f() is adjusted to 2 results
+     a,b,c = f()        -- f() is adjusted to 3 results
+     return f()         -- returns all results from f()
+     return ...         -- returns all received vararg parameters
+     return x,y,f()     -- returns x, y, and all results from f()
+     {f()}              -- creates a list with all results from f()
+     {...}              -- creates a list with all vararg parameters
+     {f(), nil}         -- f() is adjusted to 1 result
+</pre>
+
+<p>
+An expression enclosed in parentheses always results in only one value.
+Thus,
+<code>(f(x,y,z))</code> is always a single value,
+even if <code>f</code> returns several values.
+(The value of <code>(f(x,y,z))</code> is the first value returned by <code>f</code>
+or <b>nil</b> if <code>f</code> does not return any values.)
+
+
+
+<h3>2.5.1 - <a name="2.5.1">Arithmetic Operators</a></h3><p>
+Lua supports the usual arithmetic operators:
+the binary <code>+</code> (addition),
+<code>-</code> (subtraction), <code>*</code> (multiplication),
+<code>/</code> (division), <code>%</code> (modulo), and <code>^</code> (exponentiation);
+and unary <code>-</code> (negation).
+If the operands are numbers, or strings that can be converted to
+numbers (see <a href="#2.2.1">&sect;2.2.1</a>),
+then all operations have the usual meaning.
+Exponentiation works for any exponent.
+For instance, <code>x^(-0.5)</code> computes the inverse of the square root of <code>x</code>.
+Modulo is defined as
+
+<pre>
+     a % b == a - math.floor(a/b)*b
+</pre><p>
+That is, it is the remainder of a division that rounds
+the quotient towards minus infinity.
+
+
+
+
+
+<h3>2.5.2 - <a name="2.5.2">Relational Operators</a></h3><p>
+The relational operators in Lua are
+
+<pre>
+     ==    ~=    &lt;     &gt;     &lt;=    &gt;=
+</pre><p>
+These operators always result in <b>false</b> or <b>true</b>.
+
+
+<p>
+Equality (<code>==</code>) first compares the type of its operands.
+If the types are different, then the result is <b>false</b>.
+Otherwise, the values of the operands are compared.
+Numbers and strings are compared in the usual way.
+Objects (tables, userdata, threads, and functions)
+are compared by <em>reference</em>:
+two objects are considered equal only if they are the <em>same</em> object.
+Every time you create a new object
+(a table, userdata, thread, or function),
+this new object is different from any previously existing object.
+
+
+<p>
+You can change the way that Lua compares tables and userdata 
+by using the "eq" metamethod (see <a href="#2.8">&sect;2.8</a>).
+
+
+<p>
+The conversion rules of <a href="#2.2.1">&sect;2.2.1</a>
+<em>do not</em> apply to equality comparisons.
+Thus, <code>"0"==0</code> evaluates to <b>false</b>,
+and <code>t[0]</code> and <code>t["0"]</code> denote different
+entries in a table.
+
+
+<p>
+The operator <code>~=</code> is exactly the negation of equality (<code>==</code>).
+
+
+<p>
+The order operators work as follows.
+If both arguments are numbers, then they are compared as such.
+Otherwise, if both arguments are strings,
+then their values are compared according to the current locale.
+Otherwise, Lua tries to call the "lt" or the "le"
+metamethod (see <a href="#2.8">&sect;2.8</a>).
+
+
+
+
+
+<h3>2.5.3 - <a name="2.5.3">Logical Operators</a></h3><p>
+The logical operators in Lua are
+<b>and</b>, <b>or</b>, and <b>not</b>.
+Like the control structures (see <a href="#2.4.4">&sect;2.4.4</a>),
+all logical operators consider both <b>false</b> and <b>nil</b> as false
+and anything else as true.
+
+
+<p>
+The negation operator <b>not</b> always returns <b>false</b> or <b>true</b>.
+The conjunction operator <b>and</b> returns its first argument
+if this value is <b>false</b> or <b>nil</b>;
+otherwise, <b>and</b> returns its second argument.
+The disjunction operator <b>or</b> returns its first argument
+if this value is different from <b>nil</b> and <b>false</b>;
+otherwise, <b>or</b> returns its second argument.
+Both <b>and</b> and <b>or</b> use short-cut evaluation;
+that is,
+the second operand is evaluated only if necessary.
+Here are some examples:
+
+<pre>
+     10 or 20            --&gt; 10
+     10 or error()       --&gt; 10
+     nil or "a"          --&gt; "a"
+     nil and 10          --&gt; nil
+     false and error()   --&gt; false
+     false and nil       --&gt; false
+     false or nil        --&gt; nil
+     10 and 20           --&gt; 20
+</pre><p>
+(In this manual,
+--> indicates the result of the preceding expression.)
+
+
+
+
+
+<h3>2.5.4 - <a name="2.5.4">Concatenation</a></h3><p>
+The string concatenation operator in Lua is
+denoted by two dots ('<code>..</code>').
+If both operands are strings or numbers, then they are converted to
+strings according to the rules mentioned in <a href="#2.2.1">&sect;2.2.1</a>.
+Otherwise, the "concat" metamethod is called (see <a href="#2.8">&sect;2.8</a>).
+
+
+
+
+
+<h3>2.5.5 - <a name="2.5.5">The Length Operator</a></h3>
+
+<p>
+The length operator is denoted by the unary operator <code>#</code>.
+The length of a string is its number of bytes
+(that is, the usual meaning of string length when each
+character is one byte).
+
+
+<p>
+The length of a table <code>t</code> is defined to be any
+integer index <code>n</code>
+such that <code>t[n]</code> is not <b>nil</b> and <code>t[n+1]</code> is <b>nil</b>;
+moreover, if <code>t[1]</code> is <b>nil</b>, <code>n</code> may be zero.
+For a regular array, with non-nil values from 1 to a given <code>n</code>,
+its length is exactly that <code>n</code>,
+the index of its last value.
+If the array has "holes"
+(that is, <b>nil</b> values between other non-nil values),
+then <code>#t</code> may be any of the indices that
+directly precedes a <b>nil</b> value
+(that is, it may consider any such <b>nil</b> value as the end of
+the array). 
+
+
+
+
+
+<h3>2.5.6 - <a name="2.5.6">Precedence</a></h3><p>
+Operator precedence in Lua follows the table below,
+from lower to higher priority:
+
+<pre>
+     or
+     and
+     &lt;     &gt;     &lt;=    &gt;=    ~=    ==
+     ..
+     +     -
+     *     /     %
+     not   #     - (unary)
+     ^
+</pre><p>
+As usual,
+you can use parentheses to change the precedences of an expression.
+The concatenation ('<code>..</code>') and exponentiation ('<code>^</code>')
+operators are right associative.
+All other binary operators are left associative.
+
+
+
+
+
+<h3>2.5.7 - <a name="2.5.7">Table Constructors</a></h3><p>
+Table constructors are expressions that create tables.
+Every time a constructor is evaluated, a new table is created.
+Constructors can be used to create empty tables,
+or to create a table and initialize some of its fields.
+The general syntax for constructors is
+
+<pre>
+	tableconstructor ::= `<b>{</b>&acute; [fieldlist] `<b>}</b>&acute;
+	fieldlist ::= field {fieldsep field} [fieldsep]
+	field ::= `<b>[</b>&acute; exp `<b>]</b>&acute; `<b>=</b>&acute; exp | Name `<b>=</b>&acute; exp | exp
+	fieldsep ::= `<b>,</b>&acute; | `<b>;</b>&acute;
+</pre>
+
+<p>
+Each field of the form <code>[exp1] = exp2</code> adds to the new table an entry
+with key <code>exp1</code> and value <code>exp2</code>.
+A field of the form <code>name = exp</code> is equivalent to
+<code>["name"] = exp</code>.
+Finally, fields of the form <code>exp</code> are equivalent to
+<code>[i] = exp</code>, where <code>i</code> are consecutive numerical integers,
+starting with 1.
+Fields in the other formats do not affect this counting.
+For example,
+
+<pre>
+     a = { [f(1)] = g; "x", "y"; x = 1, f(x), [30] = 23; 45 }
+</pre><p>
+is equivalent to
+
+<pre>
+     do
+       local t = {}
+       t[f(1)] = g
+       t[1] = "x"         -- 1st exp
+       t[2] = "y"         -- 2nd exp
+       t.x = 1            -- t["x"] = 1
+       t[3] = f(x)        -- 3rd exp
+       t[30] = 23
+       t[4] = 45          -- 4th exp
+       a = t
+     end
+</pre>
+
+<p>
+If the last field in the list has the form <code>exp</code>
+and the expression is a function call or a vararg expression,
+then all values returned by this expression enter the list consecutively
+(see <a href="#2.5.8">&sect;2.5.8</a>).
+To avoid this,
+enclose the function call (or the vararg expression)
+in parentheses (see <a href="#2.5">&sect;2.5</a>).
+
+
+<p>
+The field list may have an optional trailing separator,
+as a convenience for machine-generated code.
+
+
+
+
+
+<h3>2.5.8 - <a name="2.5.8">Function Calls</a></h3><p>
+A function call in Lua has the following syntax:
+
+<pre>
+	functioncall ::= prefixexp args
+</pre><p>
+In a function call,
+first prefixexp and args are evaluated.
+If the value of prefixexp has type <em>function</em>,
+then this function is called
+with the given arguments.
+Otherwise, the prefixexp "call" metamethod is called,
+having as first parameter the value of prefixexp,
+followed by the original call arguments
+(see <a href="#2.8">&sect;2.8</a>).
+
+
+<p>
+The form
+
+<pre>
+	functioncall ::= prefixexp `<b>:</b>&acute; Name args
+</pre><p>
+can be used to call "methods".
+A call <code>v:name(<em>args</em>)</code>
+is syntactic sugar for <code>v.name(v,<em>args</em>)</code>,
+except that <code>v</code> is evaluated only once.
+
+
+<p>
+Arguments have the following syntax:
+
+<pre>
+	args ::= `<b>(</b>&acute; [explist] `<b>)</b>&acute;
+	args ::= tableconstructor
+	args ::= String
+</pre><p>
+All argument expressions are evaluated before the call.
+A call of the form <code>f{<em>fields</em>}</code> is
+syntactic sugar for <code>f({<em>fields</em>})</code>;
+that is, the argument list is a single new table.
+A call of the form <code>f'<em>string</em>'</code>
+(or <code>f"<em>string</em>"</code> or <code>f[[<em>string</em>]]</code>)
+is syntactic sugar for <code>f('<em>string</em>')</code>;
+that is, the argument list is a single literal string.
+
+
+<p>
+As an exception to the free-format syntax of Lua,
+you cannot put a line break before the '<code>(</code>' in a function call.
+This restriction avoids some ambiguities in the language.
+If you write
+
+<pre>
+     a = f
+     (g).x(a)
+</pre><p>
+Lua would see that as a single statement, <code>a = f(g).x(a)</code>.
+So, if you want two statements, you must add a semi-colon between them.
+If you actually want to call <code>f</code>,
+you must remove the line break before <code>(g)</code>.
+
+
+<p>
+A call of the form <code>return</code> <em>functioncall</em> is called
+a <em>tail call</em>.
+Lua implements <em>proper tail calls</em>
+(or <em>proper tail recursion</em>):
+in a tail call,
+the called function reuses the stack entry of the calling function.
+Therefore, there is no limit on the number of nested tail calls that
+a program can execute.
+However, a tail call erases any debug information about the
+calling function.
+Note that a tail call only happens with a particular syntax,
+where the <b>return</b> has one single function call as argument;
+this syntax makes the calling function return exactly
+the returns of the called function.
+So, none of the following examples are tail calls:
+
+<pre>
+     return (f(x))        -- results adjusted to 1
+     return 2 * f(x)
+     return x, f(x)       -- additional results
+     f(x); return         -- results discarded
+     return x or f(x)     -- results adjusted to 1
+</pre>
+
+
+
+
+<h3>2.5.9 - <a name="2.5.9">Function Definitions</a></h3>
+
+<p>
+The syntax for function definition is
+
+<pre>
+	function ::= <b>function</b> funcbody
+	funcbody ::= `<b>(</b>&acute; [parlist] `<b>)</b>&acute; block <b>end</b>
+</pre>
+
+<p>
+The following syntactic sugar simplifies function definitions:
+
+<pre>
+	stat ::= <b>function</b> funcname funcbody
+	stat ::= <b>local</b> <b>function</b> Name funcbody
+	funcname ::= Name {`<b>.</b>&acute; Name} [`<b>:</b>&acute; Name]
+</pre><p>
+The statement
+
+<pre>
+     function f () <em>body</em> end
+</pre><p>
+translates to
+
+<pre>
+     f = function () <em>body</em> end
+</pre><p>
+The statement
+
+<pre>
+     function t.a.b.c.f () <em>body</em> end
+</pre><p>
+translates to
+
+<pre>
+     t.a.b.c.f = function () <em>body</em> end
+</pre><p>
+The statement
+
+<pre>
+     local function f () <em>body</em> end
+</pre><p>
+translates to
+
+<pre>
+     local f; f = function () <em>body</em> end
+</pre><p>
+<em>not</em> to
+
+<pre>
+     local f = function () <em>body</em> end
+</pre><p>
+(This only makes a difference when the body of the function
+contains references to <code>f</code>.)
+
+
+<p>
+A function definition is an executable expression,
+whose value has type <em>function</em>.
+When Lua pre-compiles a chunk,
+all its function bodies are pre-compiled too.
+Then, whenever Lua executes the function definition,
+the function is <em>instantiated</em> (or <em>closed</em>).
+This function instance (or <em>closure</em>)
+is the final value of the expression.
+Different instances of the same function
+may refer to different  external local variables
+and may have different environment tables.
+
+
+<p>
+Parameters act as local variables that are
+initialized with the argument values:
+
+<pre>
+	parlist ::= namelist [`<b>,</b>&acute; `<b>...</b>&acute;] | `<b>...</b>&acute;
+</pre><p>
+When a function is called,
+the list of arguments is adjusted to
+the length of the list of parameters,
+unless the function is a variadic or <em>vararg function</em>,
+which is
+indicated by three dots ('<code>...</code>') at the end of its parameter list.
+A vararg function does not adjust its argument list;
+instead, it collects all extra arguments and supplies them
+to the function through a <em>vararg expression</em>,
+which is also written as three dots.
+The value of this expression is a list of all actual extra arguments,
+similar to a function with multiple results.
+If a vararg expression is used inside another expression
+or in the middle of a list of expressions,
+then its return list is adjusted to one element.
+If the expression is used as the last element of a list of expressions,
+then no adjustment is made
+(unless the call is enclosed in parentheses).
+
+
+<p>
+As an example, consider the following definitions:
+
+<pre>
+     function f(a, b) end
+     function g(a, b, ...) end
+     function r() return 1,2,3 end
+</pre><p>
+Then, we have the following mapping from arguments to parameters and
+to the vararg expression:
+
+<pre>
+     CALL            PARAMETERS
+     
+     f(3)             a=3, b=nil
+     f(3, 4)          a=3, b=4
+     f(3, 4, 5)       a=3, b=4
+     f(r(), 10)       a=1, b=10
+     f(r())           a=1, b=2
+     
+     g(3)             a=3, b=nil, ... --&gt;  (nothing)
+     g(3, 4)          a=3, b=4,   ... --&gt;  (nothing)
+     g(3, 4, 5, 8)    a=3, b=4,   ... --&gt;  5  8
+     g(5, r())        a=5, b=1,   ... --&gt;  2  3
+</pre>
+
+<p>
+Results are returned using the <b>return</b> statement (see <a href="#2.4.4">&sect;2.4.4</a>).
+If control reaches the end of a function
+without encountering a <b>return</b> statement,
+then the function returns with no results.
+
+
+<p>
+The <em>colon</em> syntax
+is used for defining <em>methods</em>,
+that is, functions that have an implicit extra parameter <code>self</code>.
+Thus, the statement
+
+<pre>
+     function t.a.b.c:f (<em>params</em>) <em>body</em> end
+</pre><p>
+is syntactic sugar for
+
+<pre>
+     t.a.b.c.f = function (self, <em>params</em>) <em>body</em> end
+</pre>
+
+
+
+
+
+
+<h2>2.6 - <a name="2.6">Visibility Rules</a></h2>
+
+<p>
+
+Lua is a lexically scoped language.
+The scope of variables begins at the first statement <em>after</em>
+their declaration and lasts until the end of the innermost block that
+includes the declaration.
+Consider the following example:
+
+<pre>
+     x = 10                -- global variable
+     do                    -- new block
+       local x = x         -- new 'x', with value 10
+       print(x)            --&gt; 10
+       x = x+1
+       do                  -- another block
+         local x = x+1     -- another 'x'
+         print(x)          --&gt; 12
+       end
+       print(x)            --&gt; 11
+     end
+     print(x)              --&gt; 10  (the global one)
+</pre>
+
+<p>
+Notice that, in a declaration like <code>local x = x</code>,
+the new <code>x</code> being declared is not in scope yet,
+and so the second <code>x</code> refers to the outside variable.
+
+
+<p>
+Because of the lexical scoping rules,
+local variables can be freely accessed by functions
+defined inside their scope.
+A local variable used by an inner function is called
+an <em>upvalue</em>, or <em>external local variable</em>,
+inside the inner function.
+
+
+<p>
+Notice that each execution of a <b>local</b> statement
+defines new local variables.
+Consider the following example:
+
+<pre>
+     a = {}
+     local x = 20
+     for i=1,10 do
+       local y = 0
+       a[i] = function () y=y+1; return x+y end
+     end
+</pre><p>
+The loop creates ten closures
+(that is, ten instances of the anonymous function).
+Each of these closures uses a different <code>y</code> variable,
+while all of them share the same <code>x</code>.
+
+
+
+
+
+<h2>2.7 - <a name="2.7">Error Handling</a></h2>
+
+<p>
+Because Lua is an embedded extension language,
+all Lua actions start from C&nbsp;code in the host program
+calling a function from the Lua library (see <a href="#lua_pcall"><code>lua_pcall</code></a>).
+Whenever an error occurs during Lua compilation or execution,
+control returns to C,
+which can take appropriate measures
+(such as printing an error message).
+
+
+<p>
+Lua code can explicitly generate an error by calling the
+<a href="#pdf-error"><code>error</code></a> function.
+If you need to catch errors in Lua,
+you can use the <a href="#pdf-pcall"><code>pcall</code></a> function.
+
+
+
+
+
+<h2>2.8 - <a name="2.8">Metatables</a></h2>
+
+<p>
+Every value in Lua may have a <em>metatable</em>.
+This <em>metatable</em> is an ordinary Lua table
+that defines the behavior of the original value
+under certain special operations.
+You can change several aspects of the behavior
+of operations over a value by setting specific fields in its metatable.
+For instance, when a non-numeric value is the operand of an addition,
+Lua checks for a function in the field <code>"__add"</code> in its metatable.
+If it finds one,
+Lua calls this function to perform the addition.
+
+
+<p>
+We call the keys in a metatable <em>events</em>
+and the values <em>metamethods</em>.
+In the previous example, the event is <code>"add"</code> 
+and the metamethod is the function that performs the addition.
+
+
+<p>
+You can query the metatable of any value
+through the <a href="#pdf-getmetatable"><code>getmetatable</code></a> function.
+
+
+<p>
+You can replace the metatable of tables
+through the <a href="#pdf-setmetatable"><code>setmetatable</code></a>
+function.
+You cannot change the metatable of other types from Lua
+(except using the debug library);
+you must use the C&nbsp;API for that.
+
+
+<p>
+Tables and full userdata have individual metatables
+(although multiple tables and userdata can share their metatables);
+values of all other types share one single metatable per type.
+So, there is one single metatable for all numbers,
+one for all strings, etc.
+
+
+<p>
+A metatable may control how an object behaves in arithmetic operations,
+order comparisons, concatenation, length operation, and indexing.
+A metatable can also define a function to be called when a userdata
+is garbage collected.
+For each of these operations Lua associates a specific key
+called an <em>event</em>.
+When Lua performs one of these operations over a value,
+it checks whether this value has a metatable with the corresponding event.
+If so, the value associated with that key (the metamethod)
+controls how Lua will perform the operation.
+
+
+<p>
+Metatables control the operations listed next.
+Each operation is identified by its corresponding name.
+The key for each operation is a string with its name prefixed by
+two underscores, '<code>__</code>';
+for instance, the key for operation "add" is the
+string <code>"__add"</code>.
+The semantics of these operations is better explained by a Lua function
+describing how the interpreter executes the operation.
+
+
+<p>
+The code shown here in Lua is only illustrative;
+the real behavior is hard coded in the interpreter
+and it is much more efficient than this simulation.
+All functions used in these descriptions
+(<a href="#pdf-rawget"><code>rawget</code></a>, <a href="#pdf-tonumber"><code>tonumber</code></a>, etc.)
+are described in <a href="#5.1">&sect;5.1</a>.
+In particular, to retrieve the metamethod of a given object,
+we use the expression
+
+<pre>
+     metatable(obj)[event]
+</pre><p>
+This should be read as
+
+<pre>
+     rawget(getmetatable(obj) or {}, event)
+</pre><p>
+
+That is, the access to a metamethod does not invoke other metamethods,
+and the access to objects with no metatables does not fail
+(it simply results in <b>nil</b>).
+
+
+
+<ul>
+
+<li><b>"add":</b>
+the <code>+</code> operation.
+
+
+
+<p>
+The function <code>getbinhandler</code> below defines how Lua chooses a handler
+for a binary operation.
+First, Lua tries the first operand.
+If its type does not define a handler for the operation,
+then Lua tries the second operand.
+
+<pre>
+     function getbinhandler (op1, op2, event)
+       return metatable(op1)[event] or metatable(op2)[event]
+     end
+</pre><p>
+By using this function,
+the behavior of the <code>op1 + op2</code> is
+
+<pre>
+     function add_event (op1, op2)
+       local o1, o2 = tonumber(op1), tonumber(op2)
+       if o1 and o2 then  -- both operands are numeric?
+         return o1 + o2   -- '+' here is the primitive 'add'
+       else  -- at least one of the operands is not numeric
+         local h = getbinhandler(op1, op2, "__add")
+         if h then
+           -- call the handler with both operands
+           return (h(op1, op2))
+         else  -- no handler available: default behavior
+           error(&middot;&middot;&middot;)
+         end
+       end
+     end
+</pre><p>
+</li>
+
+<li><b>"sub":</b>
+the <code>-</code> operation.
+
+Behavior similar to the "add" operation.
+</li>
+
+<li><b>"mul":</b>
+the <code>*</code> operation.
+
+Behavior similar to the "add" operation.
+</li>
+
+<li><b>"div":</b>
+the <code>/</code> operation.
+
+Behavior similar to the "add" operation.
+</li>
+
+<li><b>"mod":</b>
+the <code>%</code> operation.
+
+Behavior similar to the "add" operation,
+with the operation
+<code>o1 - floor(o1/o2)*o2</code> as the primitive operation.
+</li>
+
+<li><b>"pow":</b>
+the <code>^</code> (exponentiation) operation.
+
+Behavior similar to the "add" operation,
+with the function <code>pow</code> (from the C&nbsp;math library)
+as the primitive operation.
+</li>
+
+<li><b>"unm":</b>
+the unary <code>-</code> operation.
+
+
+<pre>
+     function unm_event (op)
+       local o = tonumber(op)
+       if o then  -- operand is numeric?
+         return -o  -- '-' here is the primitive 'unm'
+       else  -- the operand is not numeric.
+         -- Try to get a handler from the operand
+         local h = metatable(op).__unm
+         if h then
+           -- call the handler with the operand
+           return (h(op))
+         else  -- no handler available: default behavior
+           error(&middot;&middot;&middot;)
+         end
+       end
+     end
+</pre><p>
+</li>
+
+<li><b>"concat":</b>
+the <code>..</code> (concatenation) operation.
+
+
+<pre>
+     function concat_event (op1, op2)
+       if (type(op1) == "string" or type(op1) == "number") and
+          (type(op2) == "string" or type(op2) == "number") then
+         return op1 .. op2  -- primitive string concatenation
+       else
+         local h = getbinhandler(op1, op2, "__concat")
+         if h then
+           return (h(op1, op2))
+         else
+           error(&middot;&middot;&middot;)
+         end
+       end
+     end
+</pre><p>
+</li>
+
+<li><b>"len":</b>
+the <code>#</code> operation.
+
+
+<pre>
+     function len_event (op)
+       if type(op) == "string" then
+         return strlen(op)         -- primitive string length
+       elseif type(op) == "table" then
+         return #op                -- primitive table length
+       else
+         local h = metatable(op).__len
+         if h then
+           -- call the handler with the operand
+           return (h(op))
+         else  -- no handler available: default behavior
+           error(&middot;&middot;&middot;)
+         end
+       end
+     end
+</pre><p>
+See <a href="#2.5.5">&sect;2.5.5</a> for a description of the length of a table.
+</li>
+
+<li><b>"eq":</b>
+the <code>==</code> operation.
+
+The function <code>getcomphandler</code> defines how Lua chooses a metamethod
+for comparison operators.
+A metamethod only is selected when both objects
+being compared have the same type
+and the same metamethod for the selected operation.
+
+<pre>
+     function getcomphandler (op1, op2, event)
+       if type(op1) ~= type(op2) then return nil end
+       local mm1 = metatable(op1)[event]
+       local mm2 = metatable(op2)[event]
+       if mm1 == mm2 then return mm1 else return nil end
+     end
+</pre><p>
+The "eq" event is defined as follows:
+
+<pre>
+     function eq_event (op1, op2)
+       if type(op1) ~= type(op2) then  -- different types?
+         return false   -- different objects
+       end
+       if op1 == op2 then   -- primitive equal?
+         return true   -- objects are equal
+       end
+       -- try metamethod
+       local h = getcomphandler(op1, op2, "__eq")
+       if h then
+         return (h(op1, op2))
+       else
+         return false
+       end
+     end
+</pre><p>
+<code>a ~= b</code> is equivalent to <code>not (a == b)</code>.
+</li>
+
+<li><b>"lt":</b>
+the <code>&lt;</code> operation.
+
+
+<pre>
+     function lt_event (op1, op2)
+       if type(op1) == "number" and type(op2) == "number" then
+         return op1 &lt; op2   -- numeric comparison
+       elseif type(op1) == "string" and type(op2) == "string" then
+         return op1 &lt; op2   -- lexicographic comparison
+       else
+         local h = getcomphandler(op1, op2, "__lt")
+         if h then
+           return (h(op1, op2))
+         else
+           error(&middot;&middot;&middot;);
+         end
+       end
+     end
+</pre><p>
+<code>a &gt; b</code> is equivalent to <code>b &lt; a</code>.
+</li>
+
+<li><b>"le":</b>
+the <code>&lt;=</code> operation.
+
+
+<pre>
+     function le_event (op1, op2)
+       if type(op1) == "number" and type(op2) == "number" then
+         return op1 &lt;= op2   -- numeric comparison
+       elseif type(op1) == "string" and type(op2) == "string" then
+         return op1 &lt;= op2   -- lexicographic comparison
+       else
+         local h = getcomphandler(op1, op2, "__le")
+         if h then
+           return (h(op1, op2))
+         else
+           h = getcomphandler(op1, op2, "__lt")
+           if h then
+             return not h(op2, op1)
+           else
+             error(&middot;&middot;&middot;);
+           end
+         end
+       end
+     end
+</pre><p>
+<code>a &gt;= b</code> is equivalent to <code>b &lt;= a</code>.
+Note that, in the absence of a "le" metamethod,
+Lua tries the "lt", assuming that <code>a &lt;= b</code> is
+equivalent to <code>not (b &lt; a)</code>.
+</li>
+
+<li><b>"index":</b>
+The indexing access <code>table[key]</code>.
+
+
+<pre>
+     function gettable_event (table, key)
+       local h
+       if type(table) == "table" then
+         local v = rawget(table, key)
+         if v ~= nil then return v end
+         h = metatable(table).__index
+         if h == nil then return nil end
+       else
+         h = metatable(table).__index
+         if h == nil then
+           error(&middot;&middot;&middot;);
+         end
+       end
+       if type(h) == "function" then
+         return (h(table, key))     -- call the handler
+       else return h[key]           -- or repeat operation on it
+       end
+     end
+</pre><p>
+</li>
+
+<li><b>"newindex":</b>
+The indexing assignment <code>table[key] = value</code>.
+
+
+<pre>
+     function settable_event (table, key, value)
+       local h
+       if type(table) == "table" then
+         local v = rawget(table, key)
+         if v ~= nil then rawset(table, key, value); return end
+         h = metatable(table).__newindex
+         if h == nil then rawset(table, key, value); return end
+       else
+         h = metatable(table).__newindex
+         if h == nil then
+           error(&middot;&middot;&middot;);
+         end
+       end
+       if type(h) == "function" then
+         h(table, key,value)           -- call the handler
+       else h[key] = value             -- or repeat operation on it
+       end
+     end
+</pre><p>
+</li>
+
+<li><b>"call":</b>
+called when Lua calls a value.
+
+
+<pre>
+     function function_event (func, ...)
+       if type(func) == "function" then
+         return func(...)   -- primitive call
+       else
+         local h = metatable(func).__call
+         if h then
+           return h(func, ...)
+         else
+           error(&middot;&middot;&middot;)
+         end
+       end
+     end
+</pre><p>
+</li>
+
+</ul>
+
+
+
+
+<h2>2.9 - <a name="2.9">Environments</a></h2>
+
+<p>
+Besides metatables,
+objects of types thread, function, and userdata
+have another table associated with them,
+called their <em>environment</em>.
+Like metatables, environments are regular tables and
+multiple objects can share the same environment.
+
+
+<p>
+Environments associated with userdata have no meaning for Lua.
+It is only a convenience feature for programmers to associate a table to
+a userdata.
+
+
+<p>
+Environments associated with threads are called
+<em>global environments</em>.
+They are used as the default environment for their threads and
+non-nested functions created by the thread
+(through <a href="#pdf-loadfile"><code>loadfile</code></a>, <a href="#pdf-loadstring"><code>loadstring</code></a> or <a href="#pdf-load"><code>load</code></a>)
+and can be directly accessed by C&nbsp;code (see <a href="#3.3">&sect;3.3</a>).
+
+
+<p>
+Environments associated with C&nbsp;functions can be directly
+accessed by C&nbsp;code (see <a href="#3.3">&sect;3.3</a>).
+They are used as the default environment for other C&nbsp;functions
+created by the function.
+
+
+<p>
+Environments associated with Lua functions are used to resolve
+all accesses to global variables within the function (see <a href="#2.3">&sect;2.3</a>).
+They are used as the default environment for other Lua functions
+created by the function.
+
+
+<p>
+You can change the environment of a Lua function or the
+running thread by calling <a href="#pdf-setfenv"><code>setfenv</code></a>.
+You can get the environment of a Lua function or the running thread
+by calling <a href="#pdf-getfenv"><code>getfenv</code></a>.
+To manipulate the environment of other objects
+(userdata, C&nbsp;functions, other threads) you must
+use the C&nbsp;API.
+
+
+
+
+
+<h2>2.10 - <a name="2.10">Garbage Collection</a></h2>
+
+<p>
+Lua performs automatic memory management.
+This means that
+you have to worry neither about allocating memory for new objects
+nor about freeing it when the objects are no longer needed.
+Lua manages memory automatically by running
+a <em>garbage collector</em> from time to time
+to collect all <em>dead objects</em>
+(that is, these objects that are no longer accessible from Lua).
+All objects in Lua are subject to automatic management:
+tables, userdata, functions, threads, and strings.
+
+
+<p>
+Lua implements an incremental mark-and-sweep collector.
+It uses two numbers to control its garbage-collection cycles:
+the <em>garbage-collector pause</em> and
+the <em>garbage-collector step multiplier</em>.
+
+
+<p>
+The garbage-collector pause
+controls how long the collector waits before starting a new cycle.
+Larger values make the collector less aggressive.
+Values smaller than 1 mean the collector will not wait to
+start a new cycle.
+A value of 2 means that the collector waits for the total memory in use
+to double before starting a new cycle.
+
+
+<p>
+The step multiplier
+controls the relative speed of the collector relative to
+memory allocation.
+Larger values make the collector more aggressive but also increase
+the size of each incremental step.
+Values smaller than 1 make the collector too slow and
+may result in  the collector never finishing a cycle.
+The default, 2, means that the collector runs at "twice"
+the speed of memory allocation.
+
+
+<p>
+You can change these numbers by calling <a href="#lua_gc"><code>lua_gc</code></a> in C
+or <a href="#pdf-collectgarbage"><code>collectgarbage</code></a> in Lua.
+Both get percentage points as arguments
+(so an argument of 100 means a real value of 1).
+With these functions you can also control 
+the collector directly (e.g., stop and restart it).
+
+
+
+<h3>2.10.1 - <a name="2.10.1">Garbage-Collection Metamethods</a></h3>
+
+<p>
+Using the C&nbsp;API,
+you can set garbage-collector metamethods for userdata (see <a href="#2.8">&sect;2.8</a>).
+These metamethods are also called <em>finalizers</em>.
+Finalizers allow you to coordinate Lua's garbage collection
+with external resource management
+(such as closing files, network or database connections,
+or freeing your own memory).
+
+
+<p>
+Garbage userdata with a field <code>__gc</code> in their metatables are not
+collected immediately by the garbage collector.
+Instead, Lua puts them in a list.
+After the collection,
+Lua does the equivalent of the following function
+for each userdata in that list:
+
+<pre>
+     function gc_event (udata)
+       local h = metatable(udata).__gc
+       if h then
+         h(udata)
+       end
+     end
+</pre>
+
+<p>
+At the end of each garbage-collection cycle,
+the finalizers for userdata are called in <em>reverse</em>
+order of their creation,
+among those collected in that cycle.
+That is, the first finalizer to be called is the one associated
+with the userdata created last in the program.
+The userdata itself is freed only in the next garbage-collection cycle.
+
+
+
+
+
+<h3>2.10.2 - <a name="2.10.2">Weak Tables</a></h3>
+
+<p>
+A <em>weak table</em> is a table whose elements are
+<em>weak references</em>.
+A weak reference is ignored by the garbage collector.
+In other words,
+if the only references to an object are weak references,
+then the garbage collector will collect this object.
+
+
+<p>
+A weak table can have weak keys, weak values, or both.
+A table with weak keys allows the collection of its keys,
+but prevents the collection of its values.
+A table with both weak keys and weak values allows the collection of
+both keys and values.
+In any case, if either the key or the value is collected,
+the whole pair is removed from the table.
+The weakness of a table is controlled by the
+<code>__mode</code> field of its metatable.
+If the <code>__mode</code> field is a string containing the character&nbsp;'<code>k</code>',
+the keys in the table are weak.
+If <code>__mode</code> contains '<code>v</code>',
+the values in the table are weak.
+
+
+<p>
+After you use a table as a metatable,
+you should not change the value of its field <code>__mode</code>.
+Otherwise, the weak behavior of the tables controlled by this
+metatable is undefined.
+
+
+
+
+
+
+
+<h2>2.11 - <a name="2.11">Coroutines</a></h2>
+
+<p>
+Lua supports coroutines,
+also called <em>collaborative multithreading</em>.
+A coroutine in Lua represents an independent thread of execution.
+Unlike threads in multithread systems, however,
+a coroutine only suspends its execution by explicitly calling
+a yield function.
+
+
+<p>
+You create a coroutine with a call to <a href="#pdf-coroutine.create"><code>coroutine.create</code></a>.
+Its sole argument is a function
+that is the main function of the coroutine.
+The <code>create</code> function only creates a new coroutine and
+returns a handle to it (an object of type <em>thread</em>);
+it does not start the coroutine execution.
+
+
+<p>
+When you first call <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a>,
+passing as its first argument
+the thread returned by <a href="#pdf-coroutine.create"><code>coroutine.create</code></a>,
+the coroutine starts its execution,
+at the first line of its main function.
+Extra arguments passed to <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a> are passed on
+to the coroutine main function.
+After the coroutine starts running,
+it runs until it terminates or <em>yields</em>.
+
+
+<p>
+A coroutine can terminate its execution in two ways:
+normally, when its main function returns
+(explicitly or implicitly, after the last instruction);
+and abnormally, if there is an unprotected error.
+In the first case, <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a> returns <b>true</b>,
+plus any values returned by the coroutine main function.
+In case of errors, <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a> returns <b>false</b>
+plus an error message.
+
+
+<p>
+A coroutine yields by calling <a href="#pdf-coroutine.yield"><code>coroutine.yield</code></a>.
+When a coroutine yields,
+the corresponding <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a> returns immediately,
+even if the yield happens inside nested function calls
+(that is, not in the main function,
+but in a function directly or indirectly called by the main function).
+In the case of a yield, <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a> also returns <b>true</b>,
+plus any values passed to <a href="#pdf-coroutine.yield"><code>coroutine.yield</code></a>.
+The next time you resume the same coroutine,
+it continues its execution from the point where it yielded,
+with the call to <a href="#pdf-coroutine.yield"><code>coroutine.yield</code></a> returning any extra
+arguments passed to <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a>.
+
+
+<p>
+Like <a href="#pdf-coroutine.create"><code>coroutine.create</code></a>,
+the <a href="#pdf-coroutine.wrap"><code>coroutine.wrap</code></a> function also creates a coroutine,
+but instead of returning the coroutine itself,
+it returns a function that, when called, resumes the coroutine.
+Any arguments passed to this function
+go as extra arguments to <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a>.
+<a href="#pdf-coroutine.wrap"><code>coroutine.wrap</code></a> returns all the values returned by <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a>,
+except the first one (the boolean error code).
+Unlike <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a>,
+<a href="#pdf-coroutine.wrap"><code>coroutine.wrap</code></a> does not catch errors;
+any error is propagated to the caller.
+
+
+<p>
+As an example,
+consider the following code:
+
+<pre>
+     function foo (a)
+       print("foo", a)
+       return coroutine.yield(2*a)
+     end
+     
+     co = coroutine.create(function (a,b)
+           print("co-body", a, b)
+           local r = foo(a+1)
+           print("co-body", r)
+           local r, s = coroutine.yield(a+b, a-b)
+           print("co-body", r, s)
+           return b, "end"
+     end)
+            
+     print("main", coroutine.resume(co, 1, 10))
+     print("main", coroutine.resume(co, "r"))
+     print("main", coroutine.resume(co, "x", "y"))
+     print("main", coroutine.resume(co, "x", "y"))
+</pre><p>
+When you run it, it produces the following output:
+
+<pre>
+     co-body 1       10
+     foo     2
+     
+     main    true    4
+     co-body r
+     main    true    11      -9
+     co-body x       y
+     main    true    10      end
+     main    false   cannot resume dead coroutine
+</pre>
+
+
+
+
+<h1>3 - <a name="3">The Application Program Interface</a></h1>
+
+<p>
+
+This section describes the C&nbsp;API for Lua, that is,
+the set of C&nbsp;functions available to the host program to communicate
+with Lua.
+All API functions and related types and constants
+are declared in the header file <a name="pdf-lua.h"><code>lua.h</code></a>.
+
+
+<p>
+Even when we use the term "function",
+any facility in the API may be provided as a macro instead.
+All such macros use each of their arguments exactly once
+(except for the first argument, which is always a Lua state),
+and so do not generate any hidden side-effects.
+
+
+<p>
+As in most C&nbsp;libraries,
+the Lua API functions do not check their arguments for validity or consistency.
+However, you can change this behavior by compiling Lua
+with a proper definition for the macro <a name="pdf-luai_apicheck"><code>luai_apicheck</code></a>,
+in file <code>luaconf.h</code>.
+
+
+
+<h2>3.1 - <a name="3.1">The Stack</a></h2>
+
+<p>
+Lua uses a <em>virtual stack</em> to pass values to and from C.
+Each element in this stack represents a Lua value
+(<b>nil</b>, number, string, etc.).
+
+
+<p>
+Whenever Lua calls C, the called function gets a new stack,
+which is independent of previous stacks and of stacks of
+C&nbsp;functions that are still active.
+This stack initially contains any arguments to the C&nbsp;function
+and it is where the C&nbsp;function pushes its results
+to be returned to the caller (see <a href="#lua_CFunction"><code>lua_CFunction</code></a>).
+
+
+<p>
+For convenience,
+most query operations in the API do not follow a strict stack discipline.
+Instead, they can refer to any element in the stack
+by using an <em>index</em>:
+A positive index represents an <em>absolute</em> stack position
+(starting at&nbsp;1);
+a negative index represents an <em>offset</em> relative to the top of the stack.
+More specifically, if the stack has <em>n</em> elements,
+then index&nbsp;1 represents the first element
+(that is, the element that was pushed onto the stack first)
+and
+index&nbsp;<em>n</em> represents the last element;
+index&nbsp;-1 also represents the last element
+(that is, the element at the&nbsp;top)
+and index <em>-n</em> represents the first element.
+We say that an index is <em>valid</em>
+if it lies between&nbsp;1 and the stack top
+(that is, if <code>1 &le; abs(index) &le; top</code>).
+ 
+
+
+
+
+
+<h2>3.2 - <a name="3.2">Stack Size</a></h2>
+
+<p>
+When you interact with Lua API,
+you are responsible for ensuring consistency.
+In particular,
+<em>you are responsible for controlling stack overflow</em>.
+You can use the function <a href="#lua_checkstack"><code>lua_checkstack</code></a>
+to grow the stack size.
+
+
+<p>
+Whenever Lua calls C,
+it ensures that at least <a name="pdf-LUA_MINSTACK"><code>LUA_MINSTACK</code></a> stack positions are available.
+<code>LUA_MINSTACK</code> is defined as 20,
+so that usually you do not have to worry about stack space
+unless your code has loops pushing elements onto the stack.
+
+
+<p>
+Most query functions accept as indices any value inside the
+available stack space, that is, indices up to the maximum stack size
+you have set through <a href="#lua_checkstack"><code>lua_checkstack</code></a>.
+Such indices are called <em>acceptable indices</em>.
+More formally, we define an <em>acceptable index</em>
+as follows:
+
+<pre>
+     (index &lt; 0 &amp;&amp; abs(index) &lt;= top) ||
+     (index &gt; 0 &amp;&amp; index &lt;= stackspace)
+</pre><p>
+Note that 0 is never an acceptable index.
+
+
+
+
+
+<h2>3.3 - <a name="3.3">Pseudo-Indices</a></h2>
+
+<p>
+Unless otherwise noted,
+any function that accepts valid indices can also be called with
+<em>pseudo-indices</em>,
+which represent some Lua values that are accessible to C&nbsp;code
+but which are not in the stack.
+Pseudo-indices are used to access the thread environment,
+the function environment,
+the registry,
+and the upvalues of a C&nbsp;function (see <a href="#3.4">&sect;3.4</a>).
+
+
+<p>
+The thread environment (where global variables live) is
+always at pseudo-index <a name="pdf-LUA_GLOBALSINDEX"><code>LUA_GLOBALSINDEX</code></a>.
+The environment of the running C&nbsp;function is always
+at pseudo-index <a name="pdf-LUA_ENVIRONINDEX"><code>LUA_ENVIRONINDEX</code></a>.
+
+
+<p>
+To access and change the value of global variables,
+you can use regular table operations over an environment table.
+For instance, to access the value of a global variable, do
+
+<pre>
+     lua_getfield(L, LUA_GLOBALSINDEX, varname);
+</pre>
+
+
+
+
+<h2>3.4 - <a name="3.4">C Closures</a></h2>
+
+<p>
+When a C&nbsp;function is created,
+it is possible to associate some values with it,
+thus creating a <em>C&nbsp;closure</em>;
+these values are called <em>upvalues</em> and are
+accessible to the function whenever it is called
+(see <a href="#lua_pushcclosure"><code>lua_pushcclosure</code></a>).
+
+
+<p>
+Whenever a C&nbsp;function is called,
+its upvalues are located at specific pseudo-indices.
+These pseudo-indices are produced by the macro
+<a name="lua_upvalueindex"><code>lua_upvalueindex</code></a>.
+The first value associated with a function is at position
+<code>lua_upvalueindex(1)</code>, and so on.
+Any access to <code>lua_upvalueindex(<em>n</em>)</code>,
+where <em>n</em> is greater than the number of upvalues of the
+current function,
+produces an acceptable (but invalid) index.
+
+
+
+
+
+<h2>3.5 - <a name="3.5">Registry</a></h2>
+
+<p>
+Lua provides a <em>registry</em>,
+a pre-defined table that can be used by any C&nbsp;code to
+store whatever Lua value it needs to store.
+This table is always located at pseudo-index
+<a name="pdf-LUA_REGISTRYINDEX"><code>LUA_REGISTRYINDEX</code></a>.
+Any C&nbsp;library can store data into this table,
+but it should take care to choose keys different from those used
+by other libraries, to avoid collisions.
+Typically, you should use as key a string containing your library name
+or a light userdata with the address of a C&nbsp;object in your code.
+
+
+<p>
+The integer keys in the registry are used by the reference mechanism,
+implemented by the auxiliary library,
+and therefore should not be used for other purposes.
+
+
+
+
+
+<h2>3.6 - <a name="3.6">Error Handling in C</a></h2>
+
+<p>
+Internally, Lua uses the C <code>longjmp</code> facility to handle errors.
+(You can also choose to use exceptions if you use C++;
+see file <code>luaconf.h</code>.)
+When Lua faces any error
+(such as memory allocation errors, type errors, syntax errors,
+and runtime errors)
+it <em>raises</em> an error;
+that is, it does a long jump.
+A <em>protected environment</em> uses <code>setjmp</code>
+to set a recover point;
+any error jumps to the most recent active recover point.
+
+
+<p>
+Most functions in the API may throw an error,
+for instance due to a memory allocation error.
+The documentation for each function indicates whether
+it can throw errors.
+
+
+<p>
+Inside a C&nbsp;function you can throw an error by calling <a href="#lua_error"><code>lua_error</code></a>.
+
+
+
+
+
+<h2>3.7 - <a name="3.7">Functions and Types</a></h2>
+
+<p>
+Here we list all functions and types from the C&nbsp;API in
+alphabetical order.
+Each function has an indicator like this:
+<span class="apii">[-o, +p, <em>x</em>]</span>
+
+
+<p>
+The first field, <code>o</code>,
+is how many elements the function pops from the stack.
+The second field, <code>p</code>,
+is how many elements the function pushes onto the stack.
+(Any function always pushes its results after popping its arguments.)
+A field in the form <code>x|y</code> means the function may push (or pop)
+<code>x</code> or <code>y</code> elements,
+depending on the situation;
+an interrogation mark '<code>?</code>' means that
+we cannot know how many elements the function pops/pushes
+by looking only at its arguments
+(e.g., they may depend on what is on the stack).
+The third field, <code>x</code>,
+tells whether the function may throw errors:
+'<code>-</code>' means the function never throws any error;
+'<code>m</code>' means the function may throw an error
+only due to not enough memory;
+'<code>e</code>' means the function may throw other kinds of errors;
+'<code>v</code>' means the function may throw an error on purpose.
+
+
+
+<hr><h3><a name="lua_Alloc"><code>lua_Alloc</code></a></h3>
+<pre>typedef void * (*lua_Alloc) (void *ud,
+                             void *ptr,
+                             size_t osize,
+                             size_t nsize);</pre>
+
+<p>
+The type of the memory-allocation function used by Lua states.
+The allocator function must provide a
+functionality similar to <code>realloc</code>,
+but not exactly the same.
+Its arguments are
+<code>ud</code>, an opaque pointer passed to <a href="#lua_newstate"><code>lua_newstate</code></a>;
+<code>ptr</code>, a pointer to the block being allocated/reallocated/freed;
+<code>osize</code>, the original size of the block;
+<code>nsize</code>, the new size of the block.
+<code>ptr</code> is <code>NULL</code> if and only if <code>osize</code> is zero.
+When <code>nsize</code> is zero, the allocator must return <code>NULL</code>;
+if <code>osize</code> is not zero,
+it should free the block pointed to by <code>ptr</code>.
+When <code>nsize</code> is not zero, the allocator returns <code>NULL</code>
+if and only if it cannot fill the request.
+When <code>nsize</code> is not zero and <code>osize</code> is zero,
+the allocator should behave like <code>malloc</code>.
+When <code>nsize</code> and <code>osize</code> are not zero,
+the allocator behaves like <code>realloc</code>.
+Lua assumes that the allocator never fails when
+<code>osize &gt;= nsize</code>.
+
+
+<p>
+Here is a simple implementation for the allocator function.
+It is used in the auxiliary library by <a href="#luaL_newstate"><code>luaL_newstate</code></a>.
+
+<pre>
+     static void *l_alloc (void *ud, void *ptr, size_t osize,
+                                                size_t nsize) {
+       (void)ud;  (void)osize;  /* not used */
+       if (nsize == 0) {
+         free(ptr);
+         return NULL;
+       }
+       else
+         return realloc(ptr, nsize);
+     }
+</pre><p>
+This code assumes
+that <code>free(NULL)</code> has no effect and that
+<code>realloc(NULL, size)</code> is equivalent to <code>malloc(size)</code>.
+ANSI&nbsp;C ensures both behaviors.
+
+
+
+
+
+<hr><h3><a name="lua_atpanic"><code>lua_atpanic</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>lua_CFunction lua_atpanic (lua_State *L, lua_CFunction panicf);</pre>
+
+<p>
+Sets a new panic function and returns the old one.
+
+
+<p>
+If an error happens outside any protected environment,
+Lua calls a <em>panic function</em>
+and then calls <code>exit(EXIT_FAILURE)</code>,
+thus exiting the host application.
+Your panic function may avoid this exit by
+never returning (e.g., doing a long jump).
+
+
+<p>
+The panic function can access the error message at the top of the stack.
+
+
+
+
+
+<hr><h3><a name="lua_call"><code>lua_call</code></a></h3><p>
+<span class="apii">[-(nargs + 1), +nresults, <em>e</em>]</span>
+<pre>void lua_call (lua_State *L, int nargs, int nresults);</pre>
+
+<p>
+Calls a function.
+
+
+<p>
+To call a function you must use the following protocol:
+first, the function to be called is pushed onto the stack;
+then, the arguments to the function are pushed
+in direct order;
+that is, the first argument is pushed first.
+Finally you call <a href="#lua_call"><code>lua_call</code></a>;
+<code>nargs</code> is the number of arguments that you pushed onto the stack.
+All arguments and the function value are popped from the stack
+when the function is called.
+The function results are pushed onto the stack when the function returns.
+The number of results is adjusted to <code>nresults</code>,
+unless <code>nresults</code> is <a name="pdf-LUA_MULTRET"><code>LUA_MULTRET</code></a>.
+In this case, <em>all</em> results from the function are pushed.
+Lua takes care that the returned values fit into the stack space.
+The function results are pushed onto the stack in direct order
+(the first result is pushed first),
+so that after the call the last result is on the top of the stack.
+
+
+<p>
+Any error inside the called function is propagated upwards
+(with a <code>longjmp</code>).
+
+
+<p>
+The following example shows how the host program may do the
+equivalent to this Lua code:
+
+<pre>
+     a = f("how", t.x, 14)
+</pre><p>
+Here it is in&nbsp;C:
+
+<pre>
+     lua_getfield(L, LUA_GLOBALSINDEX, "f"); /* function to be called */
+     lua_pushstring(L, "how");                        /* 1st argument */
+     lua_getfield(L, LUA_GLOBALSINDEX, "t");   /* table to be indexed */
+     lua_getfield(L, -1, "x");        /* push result of t.x (2nd arg) */
+     lua_remove(L, -2);                  /* remove 't' from the stack */
+     lua_pushinteger(L, 14);                          /* 3rd argument */
+     lua_call(L, 3, 1);     /* call 'f' with 3 arguments and 1 result */
+     lua_setfield(L, LUA_GLOBALSINDEX, "a");        /* set global 'a' */
+</pre><p>
+Note that the code above is "balanced":
+at its end, the stack is back to its original configuration.
+This is considered good programming practice.
+
+
+
+
+
+<hr><h3><a name="lua_CFunction"><code>lua_CFunction</code></a></h3>
+<pre>typedef int (*lua_CFunction) (lua_State *L);</pre>
+
+<p>
+Type for C&nbsp;functions.
+
+
+<p>
+In order to communicate properly with Lua,
+a C&nbsp;function must use the following protocol,
+which defines the way parameters and results are passed:
+a C&nbsp;function receives its arguments from Lua in its stack
+in direct order (the first argument is pushed first).
+So, when the function starts,
+<code>lua_gettop(L)</code> returns the number of arguments received by the function.
+The first argument (if any) is at index 1
+and its last argument is at index <code>lua_gettop(L)</code>.
+To return values to Lua, a C&nbsp;function just pushes them onto the stack,
+in direct order (the first result is pushed first),
+and returns the number of results.
+Any other value in the stack below the results will be properly
+discarded by Lua.
+Like a Lua function, a C&nbsp;function called by Lua can also return
+many results.
+
+
+<p>
+As an example, the following function receives a variable number
+of numerical arguments and returns their average and sum:
+
+<pre>
+     static int foo (lua_State *L) {
+       int n = lua_gettop(L);    /* number of arguments */
+       lua_Number sum = 0;
+       int i;
+       for (i = 1; i &lt;= n; i++) {
+         if (!lua_isnumber(L, i)) {
+           lua_pushstring(L, "incorrect argument");
+           lua_error(L);
+         }
+         sum += lua_tonumber(L, i);
+       }
+       lua_pushnumber(L, sum/n);        /* first result */
+       lua_pushnumber(L, sum);         /* second result */
+       return 2;                   /* number of results */
+     }
+</pre>
+
+
+
+
+<hr><h3><a name="lua_checkstack"><code>lua_checkstack</code></a></h3><p>
+<span class="apii">[-0, +0, <em>m</em>]</span>
+<pre>int lua_checkstack (lua_State *L, int extra);</pre>
+
+<p>
+Ensures that there are at least <code>extra</code> free stack slots in the stack.
+It returns false if it cannot grow the stack to that size.
+This function never shrinks the stack;
+if the stack is already larger than the new size,
+it is left unchanged.
+
+
+
+
+
+<hr><h3><a name="lua_close"><code>lua_close</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>void lua_close (lua_State *L);</pre>
+
+<p>
+Destroys all objects in the given Lua state
+(calling the corresponding garbage-collection metamethods, if any)
+and frees all dynamic memory used by this state.
+On several platforms, you may not need to call this function,
+because all resources are naturally released when the host program ends.
+On the other hand, long-running programs,
+such as a daemon or a web server,
+might need to release states as soon as they are not needed,
+to avoid growing too large.
+
+
+
+
+
+<hr><h3><a name="lua_concat"><code>lua_concat</code></a></h3><p>
+<span class="apii">[-n, +1, <em>e</em>]</span>
+<pre>void lua_concat (lua_State *L, int n);</pre>
+
+<p>
+Concatenates the <code>n</code> values at the top of the stack,
+pops them, and leaves the result at the top.
+If <code>n</code>&nbsp;is&nbsp;1, the result is the single value on the stack
+(that is, the function does nothing);
+if <code>n</code> is 0, the result is the empty string.
+Concatenation is performed following the usual semantics of Lua
+(see <a href="#2.5.4">&sect;2.5.4</a>).
+
+
+
+
+
+<hr><h3><a name="lua_cpcall"><code>lua_cpcall</code></a></h3><p>
+<span class="apii">[-0, +(0|1), <em>-</em>]</span>
+<pre>int lua_cpcall (lua_State *L, lua_CFunction func, void *ud);</pre>
+
+<p>
+Calls the C&nbsp;function <code>func</code> in protected mode.
+<code>func</code> starts with only one element in its stack,
+a light userdata containing <code>ud</code>.
+In case of errors,
+<a href="#lua_cpcall"><code>lua_cpcall</code></a> returns the same error codes as <a href="#lua_pcall"><code>lua_pcall</code></a>,
+plus the error object on the top of the stack;
+otherwise, it returns zero, and does not change the stack.
+All values returned by <code>func</code> are discarded.
+
+
+
+
+
+<hr><h3><a name="lua_createtable"><code>lua_createtable</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>void lua_createtable (lua_State *L, int narr, int nrec);</pre>
+
+<p>
+Creates a new empty table and pushes it onto the stack.
+The new table has space pre-allocated
+for <code>narr</code> array elements and <code>nrec</code> non-array elements.
+This pre-allocation is useful when you know exactly how many elements
+the table will have.
+Otherwise you can use the function <a href="#lua_newtable"><code>lua_newtable</code></a>.
+
+
+
+
+
+<hr><h3><a name="lua_dump"><code>lua_dump</code></a></h3><p>
+<span class="apii">[-0, +0, <em>m</em>]</span>
+<pre>int lua_dump (lua_State *L, lua_Writer writer, void *data);</pre>
+
+<p>
+Dumps a function as a binary chunk.
+Receives a Lua function on the top of the stack
+and produces a binary chunk that,
+if loaded again,
+results in a function equivalent to the one dumped.
+As it produces parts of the chunk,
+<a href="#lua_dump"><code>lua_dump</code></a> calls function <code>writer</code> (see <a href="#lua_Writer"><code>lua_Writer</code></a>)
+with the given <code>data</code>
+to write them.
+
+
+<p>
+The value returned is the error code returned by the last
+call to the writer;
+0&nbsp;means no errors.
+
+
+<p>
+This function does not pop the Lua function from the stack.
+
+
+
+
+
+<hr><h3><a name="lua_equal"><code>lua_equal</code></a></h3><p>
+<span class="apii">[-0, +0, <em>e</em>]</span>
+<pre>int lua_equal (lua_State *L, int index1, int index2);</pre>
+
+<p>
+Returns 1 if the two values in acceptable indices <code>index1</code> and
+<code>index2</code> are equal,
+following the semantics of the Lua <code>==</code> operator
+(that is, may call metamethods).
+Otherwise returns&nbsp;0.
+Also returns&nbsp;0 if any of the indices is non valid.
+
+
+
+
+
+<hr><h3><a name="lua_error"><code>lua_error</code></a></h3><p>
+<span class="apii">[-1, +0, <em>v</em>]</span>
+<pre>int lua_error (lua_State *L);</pre>
+
+<p>
+Generates a Lua error.
+The error message (which can actually be a Lua value of any type)
+must be on the stack top.
+This function does a long jump,
+and therefore never returns.
+(see <a href="#luaL_error"><code>luaL_error</code></a>).
+
+
+
+
+
+<hr><h3><a name="lua_gc"><code>lua_gc</code></a></h3><p>
+<span class="apii">[-0, +0, <em>e</em>]</span>
+<pre>int lua_gc (lua_State *L, int what, int data);</pre>
+
+<p>
+Controls the garbage collector.
+
+
+<p>
+This function performs several tasks,
+according to the value of the parameter <code>what</code>:
+
+<ul>
+
+<li><b><code>LUA_GCSTOP</code>:</b>
+stops the garbage collector.
+</li>
+
+<li><b><code>LUA_GCRESTART</code>:</b>
+restarts the garbage collector.
+</li>
+
+<li><b><code>LUA_GCCOLLECT</code>:</b>
+performs a full garbage-collection cycle.
+</li>
+
+<li><b><code>LUA_GCCOUNT</code>:</b>
+returns the current amount of memory (in Kbytes) in use by Lua.
+</li>
+
+<li><b><code>LUA_GCCOUNTB</code>:</b>
+returns the remainder of dividing the current amount of bytes of
+memory in use by Lua by 1024.
+</li>
+
+<li><b><code>LUA_GCSTEP</code>:</b>
+performs an incremental step of garbage collection.
+The step "size" is controlled by <code>data</code>
+(larger values mean more steps) in a non-specified way.
+If you want to control the step size
+you must experimentally tune the value of <code>data</code>.
+The function returns 1 if the step finished a
+garbage-collection cycle.
+</li>
+
+<li><b><code>LUA_GCSETPAUSE</code>:</b>
+sets <code>data</code>/100 as the new value
+for the <em>pause</em> of the collector (see <a href="#2.10">&sect;2.10</a>).
+The function returns the previous value of the pause.
+</li>
+
+<li><b><code>LUA_GCSETSTEPMUL</code>:</b>
+sets <code>data</code>/100 as the new value for the <em>step multiplier</em> of
+the collector (see <a href="#2.10">&sect;2.10</a>).
+The function returns the previous value of the step multiplier.
+</li>
+
+</ul>
+
+
+
+
+<hr><h3><a name="lua_getallocf"><code>lua_getallocf</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>lua_Alloc lua_getallocf (lua_State *L, void **ud);</pre>
+
+<p>
+Returns the memory-allocation function of a given state.
+If <code>ud</code> is not <code>NULL</code>, Lua stores in <code>*ud</code> the
+opaque pointer passed to <a href="#lua_newstate"><code>lua_newstate</code></a>.
+
+
+
+
+
+<hr><h3><a name="lua_getfenv"><code>lua_getfenv</code></a></h3><p>
+<span class="apii">[-0, +1, <em>-</em>]</span>
+<pre>void lua_getfenv (lua_State *L, int index);</pre>
+
+<p>
+Pushes onto the stack the environment table of
+the value at the given index.
+
+
+
+
+
+<hr><h3><a name="lua_getfield"><code>lua_getfield</code></a></h3><p>
+<span class="apii">[-0, +1, <em>e</em>]</span>
+<pre>void lua_getfield (lua_State *L, int index, const char *k);</pre>
+
+<p>
+Pushes onto the stack the value <code>t[k]</code>,
+where <code>t</code> is the value at the given valid index.
+As in Lua, this function may trigger a metamethod
+for the "index" event (see <a href="#2.8">&sect;2.8</a>).
+
+
+
+
+
+<hr><h3><a name="lua_getglobal"><code>lua_getglobal</code></a></h3><p>
+<span class="apii">[-0, +1, <em>e</em>]</span>
+<pre>void lua_getglobal (lua_State *L, const char *name);</pre>
+
+<p>
+Pushes onto the stack the value of the global <code>name</code>.
+It is defined as a macro:
+
+<pre>
+     #define lua_getglobal(L,s)  lua_getfield(L, LUA_GLOBALSINDEX, s)
+</pre>
+
+
+
+
+<hr><h3><a name="lua_getmetatable"><code>lua_getmetatable</code></a></h3><p>
+<span class="apii">[-0, +(0|1), <em>-</em>]</span>
+<pre>int lua_getmetatable (lua_State *L, int index);</pre>
+
+<p>
+Pushes onto the stack the metatable of the value at the given
+acceptable index.
+If the index is not valid,
+or if the value does not have a metatable,
+the function returns&nbsp;0 and pushes nothing on the stack.
+
+
+
+
+
+<hr><h3><a name="lua_gettable"><code>lua_gettable</code></a></h3><p>
+<span class="apii">[-1, +1, <em>e</em>]</span>
+<pre>void lua_gettable (lua_State *L, int index);</pre>
+
+<p>
+Pushes onto the stack the value <code>t[k]</code>,
+where <code>t</code> is the value at the given valid index
+and <code>k</code> is the value at the top of the stack.
+
+
+<p>
+This function pops the key from the stack
+(putting the resulting value in its place).
+As in Lua, this function may trigger a metamethod
+for the "index" event (see <a href="#2.8">&sect;2.8</a>).
+
+
+
+
+
+<hr><h3><a name="lua_gettop"><code>lua_gettop</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_gettop (lua_State *L);</pre>
+
+<p>
+Returns the index of the top element in the stack.
+Because indices start at&nbsp;1,
+this result is equal to the number of elements in the stack
+(and so 0&nbsp;means an empty stack).
+
+
+
+
+
+<hr><h3><a name="lua_insert"><code>lua_insert</code></a></h3><p>
+<span class="apii">[-1, +1, <em>-</em>]</span>
+<pre>void lua_insert (lua_State *L, int index);</pre>
+
+<p>
+Moves the top element into the given valid index,
+shifting up the elements above this index to open space.
+Cannot be called with a pseudo-index,
+because a pseudo-index is not an actual stack position.
+
+
+
+
+
+<hr><h3><a name="lua_Integer"><code>lua_Integer</code></a></h3>
+<pre>typedef ptrdiff_t lua_Integer;</pre>
+
+<p>
+The type used by the Lua API to represent integral values.
+
+
+<p>
+By default it is a <code>ptrdiff_t</code>,
+which is usually the largest signed integral type the machine handles
+"comfortably".
+
+
+
+
+
+<hr><h3><a name="lua_isboolean"><code>lua_isboolean</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_isboolean (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given acceptable index has type boolean,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_iscfunction"><code>lua_iscfunction</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_iscfunction (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given acceptable index is a C&nbsp;function,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isfunction"><code>lua_isfunction</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_isfunction (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given acceptable index is a function
+(either C or Lua), and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_islightuserdata"><code>lua_islightuserdata</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_islightuserdata (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given acceptable index is a light userdata,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isnil"><code>lua_isnil</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_isnil (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given acceptable index is <b>nil</b>,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isnone"><code>lua_isnone</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_isnone (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the given acceptable index is not valid
+(that is, it refers to an element outside the current stack),
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isnoneornil"><code>lua_isnoneornil</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_isnoneornil (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the given acceptable index is not valid
+(that is, it refers to an element outside the current stack)
+or if the value at this index is <b>nil</b>,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isnumber"><code>lua_isnumber</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_isnumber (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given acceptable index is a number
+or a string convertible to a number,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isstring"><code>lua_isstring</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_isstring (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given acceptable index is a string
+or a number (which is always convertible to a string),
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_istable"><code>lua_istable</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_istable (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given acceptable index is a table,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isthread"><code>lua_isthread</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_isthread (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given acceptable index is a thread,
+and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_isuserdata"><code>lua_isuserdata</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_isuserdata (lua_State *L, int index);</pre>
+
+<p>
+Returns 1 if the value at the given acceptable index is a userdata
+(either full or light), and 0&nbsp;otherwise.
+
+
+
+
+
+<hr><h3><a name="lua_lessthan"><code>lua_lessthan</code></a></h3><p>
+<span class="apii">[-0, +0, <em>e</em>]</span>
+<pre>int lua_lessthan (lua_State *L, int index1, int index2);</pre>
+
+<p>
+Returns 1 if the value at acceptable index <code>index1</code> is smaller
+than the value at acceptable index <code>index2</code>,
+following the semantics of the Lua <code>&lt;</code> operator
+(that is, may call metamethods).
+Otherwise returns&nbsp;0.
+Also returns&nbsp;0 if any of the indices is non valid.
+
+
+
+
+
+<hr><h3><a name="lua_load"><code>lua_load</code></a></h3><p>
+<span class="apii">[-0, +1, <em>-</em>]</span>
+<pre>int lua_load (lua_State *L,
+              lua_Reader reader,
+              void *data,
+              const char *chunkname);</pre>
+
+<p>
+Loads a Lua chunk.
+If there are no errors,
+<a href="#lua_load"><code>lua_load</code></a> pushes the compiled chunk as a Lua
+function on top of the stack.
+Otherwise, it pushes an error message.
+The return values of <a href="#lua_load"><code>lua_load</code></a> are:
+
+<ul>
+
+<li><b>0:</b> no errors;</li>
+
+<li><b><a name="pdf-LUA_ERRSYNTAX"><code>LUA_ERRSYNTAX</code></a>:</b>
+syntax error during pre-compilation;</li>
+
+<li><b><a href="#pdf-LUA_ERRMEM"><code>LUA_ERRMEM</code></a>:</b>
+memory allocation error.</li>
+
+</ul>
+
+<p>
+This function only loads a chunk;
+it does not run it.
+
+
+<p>
+<a href="#lua_load"><code>lua_load</code></a> automatically detects whether the chunk is text or binary,
+and loads it accordingly (see program <code>luac</code>).
+
+
+<p>
+The <a href="#lua_load"><code>lua_load</code></a> function uses a user-supplied <code>reader</code> function
+to read the chunk (see <a href="#lua_Reader"><code>lua_Reader</code></a>).
+The <code>data</code> argument is an opaque value passed to the reader function.
+
+
+<p>
+The <code>chunkname</code> argument gives a name to the chunk,
+which is used for error messages and in debug information (see <a href="#3.8">&sect;3.8</a>).
+
+
+
+
+
+<hr><h3><a name="lua_newstate"><code>lua_newstate</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>lua_State *lua_newstate (lua_Alloc f, void *ud);</pre>
+
+<p>
+Creates a new, independent state.
+Returns <code>NULL</code> if cannot create the state
+(due to lack of memory).
+The argument <code>f</code> is the allocator function;
+Lua does all memory allocation for this state through this function.
+The second argument, <code>ud</code>, is an opaque pointer that Lua
+simply passes to the allocator in every call.
+
+
+
+
+
+<hr><h3><a name="lua_newtable"><code>lua_newtable</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>void lua_newtable (lua_State *L);</pre>
+
+<p>
+Creates a new empty table and pushes it onto the stack.
+It is equivalent to <code>lua_createtable(L, 0, 0)</code>.
+
+
+
+
+
+<hr><h3><a name="lua_newthread"><code>lua_newthread</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>lua_State *lua_newthread (lua_State *L);</pre>
+
+<p>
+Creates a new thread, pushes it on the stack,
+and returns a pointer to a <a href="#lua_State"><code>lua_State</code></a> that represents this new thread.
+The new state returned by this function shares with the original state
+all global objects (such as tables),
+but has an independent execution stack.
+
+
+<p>
+There is no explicit function to close or to destroy a thread.
+Threads are subject to garbage collection,
+like any Lua object.
+
+
+
+
+
+<hr><h3><a name="lua_newuserdata"><code>lua_newuserdata</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>void *lua_newuserdata (lua_State *L, size_t size);</pre>
+
+<p>
+This function allocates a new block of memory with the given size,
+pushes onto the stack a new full userdata with the block address,
+and returns this address.
+
+
+<p>
+Userdata represent C&nbsp;values in Lua.
+A <em>full userdata</em> represents a block of memory.
+It is an object (like a table):
+you must create it, it can have its own metatable,
+and you can detect when it is being collected.
+A full userdata is only equal to itself (under raw equality).
+
+
+<p>
+When Lua collects a full userdata with a <code>gc</code> metamethod,
+Lua calls the metamethod and marks the userdata as finalized.
+When this userdata is collected again then
+Lua frees its corresponding memory.
+
+
+
+
+
+<hr><h3><a name="lua_next"><code>lua_next</code></a></h3><p>
+<span class="apii">[-1, +(2|0), <em>e</em>]</span>
+<pre>int lua_next (lua_State *L, int index);</pre>
+
+<p>
+Pops a key from the stack,
+and pushes a key-value pair from the table at the given index
+(the "next" pair after the given key).
+If there are no more elements in the table,
+then <a href="#lua_next"><code>lua_next</code></a> returns 0 (and pushes nothing).
+
+
+<p>
+A typical traversal looks like this:
+
+<pre>
+     /* table is in the stack at index 't' */
+     lua_pushnil(L);  /* first key */
+     while (lua_next(L, t) != 0) {
+       /* uses 'key' (at index -2) and 'value' (at index -1) */
+       printf("%s - %s\n",
+              lua_typename(L, lua_type(L, -2)),
+              lua_typename(L, lua_type(L, -1)));
+       /* removes 'value'; keeps 'key' for next iteration */
+       lua_pop(L, 1);
+     }
+</pre>
+
+<p>
+While traversing a table,
+do not call <a href="#lua_tolstring"><code>lua_tolstring</code></a> directly on a key,
+unless you know that the key is actually a string.
+Recall that <a href="#lua_tolstring"><code>lua_tolstring</code></a> <em>changes</em>
+the value at the given index;
+this confuses the next call to <a href="#lua_next"><code>lua_next</code></a>.
+
+
+
+
+
+<hr><h3><a name="lua_Number"><code>lua_Number</code></a></h3>
+<pre>typedef double lua_Number;</pre>
+
+<p>
+The type of numbers in Lua.
+By default, it is double, but that can be changed in <code>luaconf.h</code>.
+
+
+<p>
+Through the configuration file you can change
+Lua to operate with another type for numbers (e.g., float or long).
+
+
+
+
+
+<hr><h3><a name="lua_objlen"><code>lua_objlen</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>size_t lua_objlen (lua_State *L, int index);</pre>
+
+<p>
+Returns the "length" of the value at the given acceptable index:
+for strings, this is the string length;
+for tables, this is the result of the length operator ('<code>#</code>');
+for userdata, this is the size of the block of memory allocated
+for the userdata;
+for other values, it is&nbsp;0.
+
+
+
+
+
+<hr><h3><a name="lua_pcall"><code>lua_pcall</code></a></h3><p>
+<span class="apii">[-(nargs + 1), +(nresults|1), <em>-</em>]</span>
+<pre>int lua_pcall (lua_State *L, int nargs, int nresults, int errfunc);</pre>
+
+<p>
+Calls a function in protected mode.
+
+
+<p>
+Both <code>nargs</code> and <code>nresults</code> have the same meaning as
+in <a href="#lua_call"><code>lua_call</code></a>.
+If there are no errors during the call,
+<a href="#lua_pcall"><code>lua_pcall</code></a> behaves exactly like <a href="#lua_call"><code>lua_call</code></a>.
+However, if there is any error,
+<a href="#lua_pcall"><code>lua_pcall</code></a> catches it,
+pushes a single value on the stack (the error message),
+and returns an error code.
+Like <a href="#lua_call"><code>lua_call</code></a>,
+<a href="#lua_pcall"><code>lua_pcall</code></a> always removes the function
+and its arguments from the stack.
+
+
+<p>
+If <code>errfunc</code> is 0,
+then the error message returned on the stack
+is exactly the original error message.
+Otherwise, <code>errfunc</code> is the stack index of an
+<em>error handler function</em>.
+(In the current implementation, this index cannot be a pseudo-index.)
+In case of runtime errors,
+this function will be called with the error message
+and its return value will be the message returned on the stack by <a href="#lua_pcall"><code>lua_pcall</code></a>.
+
+
+<p>
+Typically, the error handler function is used to add more debug
+information to the error message, such as a stack traceback.
+Such information cannot be gathered after the return of <a href="#lua_pcall"><code>lua_pcall</code></a>,
+since by then the stack has unwound.
+
+
+<p>
+The <a href="#lua_pcall"><code>lua_pcall</code></a> function returns 0 in case of success
+or one of the following error codes
+(defined in <code>lua.h</code>):
+
+<ul>
+
+<li><b><a name="pdf-LUA_ERRRUN"><code>LUA_ERRRUN</code></a>:</b>
+a runtime error.
+</li>
+
+<li><b><a name="pdf-LUA_ERRMEM"><code>LUA_ERRMEM</code></a>:</b>
+memory allocation error.
+For such errors, Lua does not call the error handler function.
+</li>
+
+<li><b><a name="pdf-LUA_ERRERR"><code>LUA_ERRERR</code></a>:</b>
+error while running the error handler function.
+</li>
+
+</ul>
+
+
+
+
+<hr><h3><a name="lua_pop"><code>lua_pop</code></a></h3><p>
+<span class="apii">[-n, +0, <em>-</em>]</span>
+<pre>void lua_pop (lua_State *L, int n);</pre>
+
+<p>
+Pops <code>n</code> elements from the stack.
+
+
+
+
+
+<hr><h3><a name="lua_pushboolean"><code>lua_pushboolean</code></a></h3><p>
+<span class="apii">[-0, +1, <em>-</em>]</span>
+<pre>void lua_pushboolean (lua_State *L, int b);</pre>
+
+<p>
+Pushes a boolean value with value <code>b</code> onto the stack.
+
+
+
+
+
+<hr><h3><a name="lua_pushcclosure"><code>lua_pushcclosure</code></a></h3><p>
+<span class="apii">[-n, +1, <em>m</em>]</span>
+<pre>void lua_pushcclosure (lua_State *L, lua_CFunction fn, int n);</pre>
+
+<p>
+Pushes a new C&nbsp;closure onto the stack.
+
+
+<p>
+When a C&nbsp;function is created,
+it is possible to associate some values with it,
+thus creating a C&nbsp;closure (see <a href="#3.4">&sect;3.4</a>);
+these values are then accessible to the function whenever it is called.
+To associate values with a C&nbsp;function,
+first these values should be pushed onto the stack
+(when there are multiple values, the first value is pushed first).
+Then <a href="#lua_pushcclosure"><code>lua_pushcclosure</code></a>
+is called to create and push the C&nbsp;function onto the stack,
+with the argument <code>n</code> telling how many values should be
+associated with the function.
+<a href="#lua_pushcclosure"><code>lua_pushcclosure</code></a> also pops these values from the stack.
+
+
+
+
+
+<hr><h3><a name="lua_pushcfunction"><code>lua_pushcfunction</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>void lua_pushcfunction (lua_State *L, lua_CFunction f);</pre>
+
+<p>
+Pushes a C&nbsp;function onto the stack.
+This function receives a pointer to a C function
+and pushes onto the stack a Lua value of type <code>function</code> that,
+when called, invokes the corresponding C&nbsp;function.
+
+
+<p>
+Any function to be registered in Lua must
+follow the correct protocol to receive its parameters
+and return its results (see <a href="#lua_CFunction"><code>lua_CFunction</code></a>).
+
+
+<p>
+<code>lua_pushcfunction</code> is defined as a macro:
+
+<pre>
+     #define lua_pushcfunction(L,f)  lua_pushcclosure(L,f,0)
+</pre>
+
+
+
+
+<hr><h3><a name="lua_pushfstring"><code>lua_pushfstring</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>const char *lua_pushfstring (lua_State *L, const char *fmt, ...);</pre>
+
+<p>
+Pushes onto the stack a formatted string
+and returns a pointer to this string.
+It is similar to the C&nbsp;function <code>sprintf</code>,
+but has some important differences:
+
+<ul>
+
+<li>
+You do not have to allocate space for the result:
+the result is a Lua string and Lua takes care of memory allocation
+(and deallocation, through garbage collection).
+</li>
+
+<li>
+The conversion specifiers are quite restricted.
+There are no flags, widths, or precisions.
+The conversion specifiers can only be
+'<code>%%</code>' (inserts a '<code>%</code>' in the string),
+'<code>%s</code>' (inserts a zero-terminated string, with no size restrictions),
+'<code>%f</code>' (inserts a <a href="#lua_Number"><code>lua_Number</code></a>),
+'<code>%p</code>' (inserts a pointer as a hexadecimal numeral),
+'<code>%d</code>' (inserts an <code>int</code>), and
+'<code>%c</code>' (inserts an <code>int</code> as a character).
+</li>
+
+</ul>
+
+
+
+
+<hr><h3><a name="lua_pushinteger"><code>lua_pushinteger</code></a></h3><p>
+<span class="apii">[-0, +1, <em>-</em>]</span>
+<pre>void lua_pushinteger (lua_State *L, lua_Integer n);</pre>
+
+<p>
+Pushes a number with value <code>n</code> onto the stack.
+
+
+
+
+
+<hr><h3><a name="lua_pushlightuserdata"><code>lua_pushlightuserdata</code></a></h3><p>
+<span class="apii">[-0, +1, <em>-</em>]</span>
+<pre>void lua_pushlightuserdata (lua_State *L, void *p);</pre>
+
+<p>
+Pushes a light userdata onto the stack.
+
+
+<p>
+Userdata represent C&nbsp;values in Lua.
+A <em>light userdata</em> represents a pointer.
+It is a value (like a number):
+you do not create it, it has no individual metatable,
+and it is not collected (as it was never created).
+A light userdata is equal to "any"
+light userdata with the same C&nbsp;address.
+
+
+
+
+
+<hr><h3><a name="lua_pushliteral"><code>lua_pushliteral</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>void lua_pushliteral (lua_State *L, const char *s);</pre>
+
+<p>
+This macro is equivalent to <a href="#lua_pushlstring"><code>lua_pushlstring</code></a>,
+but can be used only when <code>s</code> is a literal string.
+In these cases, it automatically provides the string length.
+
+
+
+
+
+<hr><h3><a name="lua_pushlstring"><code>lua_pushlstring</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>void lua_pushlstring (lua_State *L, const char *s, size_t len);</pre>
+
+<p>
+Pushes the string pointed to by <code>s</code> with size <code>len</code>
+onto the stack.
+Lua makes (or reuses) an internal copy of the given string,
+so the memory at <code>s</code> can be freed or reused immediately after
+the function returns.
+The string can contain embedded zeros.
+
+
+
+
+
+<hr><h3><a name="lua_pushnil"><code>lua_pushnil</code></a></h3><p>
+<span class="apii">[-0, +1, <em>-</em>]</span>
+<pre>void lua_pushnil (lua_State *L);</pre>
+
+<p>
+Pushes a nil value onto the stack.
+
+
+
+
+
+<hr><h3><a name="lua_pushnumber"><code>lua_pushnumber</code></a></h3><p>
+<span class="apii">[-0, +1, <em>-</em>]</span>
+<pre>void lua_pushnumber (lua_State *L, lua_Number n);</pre>
+
+<p>
+Pushes a number with value <code>n</code> onto the stack.
+
+
+
+
+
+<hr><h3><a name="lua_pushstring"><code>lua_pushstring</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>void lua_pushstring (lua_State *L, const char *s);</pre>
+
+<p>
+Pushes the zero-terminated string pointed to by <code>s</code>
+onto the stack.
+Lua makes (or reuses) an internal copy of the given string,
+so the memory at <code>s</code> can be freed or reused immediately after
+the function returns.
+The string cannot contain embedded zeros;
+it is assumed to end at the first zero.
+
+
+
+
+
+<hr><h3><a name="lua_pushthread"><code>lua_pushthread</code></a></h3><p>
+<span class="apii">[-0, +1, <em>-</em>]</span>
+<pre>int lua_pushthread (lua_State *L);</pre>
+
+<p>
+Pushes the thread represented by <code>L</code> onto the stack.
+Returns 1 if this thread is the main thread of its state.
+
+
+
+
+
+<hr><h3><a name="lua_pushvalue"><code>lua_pushvalue</code></a></h3><p>
+<span class="apii">[-0, +1, <em>-</em>]</span>
+<pre>void lua_pushvalue (lua_State *L, int index);</pre>
+
+<p>
+Pushes a copy of the element at the given valid index
+onto the stack.
+
+
+
+
+
+<hr><h3><a name="lua_pushvfstring"><code>lua_pushvfstring</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>const char *lua_pushvfstring (lua_State *L,
+                              const char *fmt,
+                              va_list argp);</pre>
+
+<p>
+Equivalent to <a href="#lua_pushfstring"><code>lua_pushfstring</code></a>, except that it receives a <code>va_list</code>
+instead of a variable number of arguments.
+
+
+
+
+
+<hr><h3><a name="lua_rawequal"><code>lua_rawequal</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_rawequal (lua_State *L, int index1, int index2);</pre>
+
+<p>
+Returns 1 if the two values in acceptable indices <code>index1</code> and
+<code>index2</code> are primitively equal
+(that is, without calling metamethods).
+Otherwise returns&nbsp;0.
+Also returns&nbsp;0 if any of the indices are non valid.
+
+
+
+
+
+<hr><h3><a name="lua_rawget"><code>lua_rawget</code></a></h3><p>
+<span class="apii">[-1, +1, <em>-</em>]</span>
+<pre>void lua_rawget (lua_State *L, int index);</pre>
+
+<p>
+Similar to <a href="#lua_gettable"><code>lua_gettable</code></a>, but does a raw access
+(i.e., without metamethods).
+
+
+
+
+
+<hr><h3><a name="lua_rawgeti"><code>lua_rawgeti</code></a></h3><p>
+<span class="apii">[-0, +1, <em>-</em>]</span>
+<pre>void lua_rawgeti (lua_State *L, int index, int n);</pre>
+
+<p>
+Pushes onto the stack the value <code>t[n]</code>,
+where <code>t</code> is the value at the given valid index.
+The access is raw;
+that is, it does not invoke metamethods.
+
+
+
+
+
+<hr><h3><a name="lua_rawset"><code>lua_rawset</code></a></h3><p>
+<span class="apii">[-2, +0, <em>m</em>]</span>
+<pre>void lua_rawset (lua_State *L, int index);</pre>
+
+<p>
+Similar to <a href="#lua_settable"><code>lua_settable</code></a>, but does a raw assignment
+(i.e., without metamethods).
+
+
+
+
+
+<hr><h3><a name="lua_rawseti"><code>lua_rawseti</code></a></h3><p>
+<span class="apii">[-1, +0, <em>m</em>]</span>
+<pre>void lua_rawseti (lua_State *L, int index, int n);</pre>
+
+<p>
+Does the equivalent of <code>t[n] = v</code>,
+where <code>t</code> is the value at the given valid index
+and <code>v</code> is the value at the top of the stack.
+
+
+<p>
+This function pops the value from the stack.
+The assignment is raw;
+that is, it does not invoke metamethods.
+
+
+
+
+
+<hr><h3><a name="lua_Reader"><code>lua_Reader</code></a></h3>
+<pre>typedef const char * (*lua_Reader) (lua_State *L,
+                                    void *data,
+                                    size_t *size);</pre>
+
+<p>
+The reader function used by <a href="#lua_load"><code>lua_load</code></a>.
+Every time it needs another piece of the chunk,
+<a href="#lua_load"><code>lua_load</code></a> calls the reader,
+passing along its <code>data</code> parameter.
+The reader must return a pointer to a block of memory
+with a new piece of the chunk
+and set <code>size</code> to the block size.
+The block must exist until the reader function is called again.
+To signal the end of the chunk, the reader must return <code>NULL</code>.
+The reader function may return pieces of any size greater than zero.
+
+
+
+
+
+<hr><h3><a name="lua_register"><code>lua_register</code></a></h3><p>
+<span class="apii">[-0, +0, <em>e</em>]</span>
+<pre>void lua_register (lua_State *L,
+                   const char *name,
+                   lua_CFunction f);</pre>
+
+<p>
+Sets the C function <code>f</code> as the new value of global <code>name</code>.
+It is defined as a macro:
+
+<pre>
+     #define lua_register(L,n,f) \
+            (lua_pushcfunction(L, f), lua_setglobal(L, n))
+</pre>
+
+
+
+
+<hr><h3><a name="lua_remove"><code>lua_remove</code></a></h3><p>
+<span class="apii">[-1, +0, <em>-</em>]</span>
+<pre>void lua_remove (lua_State *L, int index);</pre>
+
+<p>
+Removes the element at the given valid index,
+shifting down the elements above this index to fill the gap.
+Cannot be called with a pseudo-index,
+because a pseudo-index is not an actual stack position.
+
+
+
+
+
+<hr><h3><a name="lua_replace"><code>lua_replace</code></a></h3><p>
+<span class="apii">[-1, +0, <em>-</em>]</span>
+<pre>void lua_replace (lua_State *L, int index);</pre>
+
+<p>
+Moves the top element into the given position (and pops it),
+without shifting any element
+(therefore replacing the value at the given position).
+
+
+
+
+
+<hr><h3><a name="lua_resume"><code>lua_resume</code></a></h3><p>
+<span class="apii">[-?, +?, <em>-</em>]</span>
+<pre>int lua_resume (lua_State *L, int narg);</pre>
+
+<p>
+Starts and resumes a coroutine in a given thread.
+
+
+<p>
+To start a coroutine, you first create a new thread
+(see <a href="#lua_newthread"><code>lua_newthread</code></a>);
+then you push onto its stack the main function plus any arguments;
+then you call <a href="#lua_resume"><code>lua_resume</code></a>,
+with <code>narg</code> being the number of arguments.
+This call returns when the coroutine suspends or finishes its execution.
+When it returns, the stack contains all values passed to <a href="#lua_yield"><code>lua_yield</code></a>,
+or all values returned by the body function.
+<a href="#lua_resume"><code>lua_resume</code></a> returns
+<a href="#pdf-LUA_YIELD"><code>LUA_YIELD</code></a> if the coroutine yields,
+0 if the coroutine finishes its execution
+without errors,
+or an error code in case of errors (see <a href="#lua_pcall"><code>lua_pcall</code></a>).
+In case of errors,
+the stack is not unwound,
+so you can use the debug API over it.
+The error message is on the top of the stack.
+To restart a coroutine, you put on its stack only the values to
+be passed as results from <code>yield</code>,
+and then call <a href="#lua_resume"><code>lua_resume</code></a>.
+
+
+
+
+
+<hr><h3><a name="lua_setallocf"><code>lua_setallocf</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>void lua_setallocf (lua_State *L, lua_Alloc f, void *ud);</pre>
+
+<p>
+Changes the allocator function of a given state to <code>f</code>
+with user data <code>ud</code>.
+
+
+
+
+
+<hr><h3><a name="lua_setfenv"><code>lua_setfenv</code></a></h3><p>
+<span class="apii">[-1, +0, <em>-</em>]</span>
+<pre>int lua_setfenv (lua_State *L, int index);</pre>
+
+<p>
+Pops a table from the stack and sets it as
+the new environment for the value at the given index.
+If the value at the given index is
+neither a function nor a thread nor a userdata,
+<a href="#lua_setfenv"><code>lua_setfenv</code></a> returns 0.
+Otherwise it returns 1.
+
+
+
+
+
+<hr><h3><a name="lua_setfield"><code>lua_setfield</code></a></h3><p>
+<span class="apii">[-1, +0, <em>e</em>]</span>
+<pre>void lua_setfield (lua_State *L, int index, const char *k);</pre>
+
+<p>
+Does the equivalent to <code>t[k] = v</code>,
+where <code>t</code> is the value at the given valid index
+and <code>v</code> is the value at the top of the stack.
+
+
+<p>
+This function pops the value from the stack.
+As in Lua, this function may trigger a metamethod
+for the "newindex" event (see <a href="#2.8">&sect;2.8</a>).
+
+
+
+
+
+<hr><h3><a name="lua_setglobal"><code>lua_setglobal</code></a></h3><p>
+<span class="apii">[-1, +0, <em>e</em>]</span>
+<pre>void lua_setglobal (lua_State *L, const char *name);</pre>
+
+<p>
+Pops a value from the stack and
+sets it as the new value of global <code>name</code>.
+It is defined as a macro:
+
+<pre>
+     #define lua_setglobal(L,s)   lua_setfield(L, LUA_GLOBALSINDEX, s)
+</pre>
+
+
+
+
+<hr><h3><a name="lua_setmetatable"><code>lua_setmetatable</code></a></h3><p>
+<span class="apii">[-1, +0, <em>-</em>]</span>
+<pre>int lua_setmetatable (lua_State *L, int index);</pre>
+
+<p>
+Pops a table from the stack and
+sets it as the new metatable for the value at the given
+acceptable index.
+
+
+
+
+
+<hr><h3><a name="lua_settable"><code>lua_settable</code></a></h3><p>
+<span class="apii">[-2, +0, <em>e</em>]</span>
+<pre>void lua_settable (lua_State *L, int index);</pre>
+
+<p>
+Does the equivalent to <code>t[k] = v</code>,
+where <code>t</code> is the value at the given valid index,
+<code>v</code> is the value at the top of the stack,
+and <code>k</code> is the value just below the top.
+
+
+<p>
+This function pops both the key and the value from the stack.
+As in Lua, this function may trigger a metamethod
+for the "newindex" event (see <a href="#2.8">&sect;2.8</a>).
+
+
+
+
+
+<hr><h3><a name="lua_settop"><code>lua_settop</code></a></h3><p>
+<span class="apii">[-?, +?, <em>-</em>]</span>
+<pre>void lua_settop (lua_State *L, int index);</pre>
+
+<p>
+Accepts any acceptable index, or&nbsp;0,
+and sets the stack top to this index.
+If the new top is larger than the old one,
+then the new elements are filled with <b>nil</b>.
+If <code>index</code> is&nbsp;0, then all stack elements are removed.
+
+
+
+
+
+<hr><h3><a name="lua_State"><code>lua_State</code></a></h3>
+<pre>typedef struct lua_State lua_State;</pre>
+
+<p>
+Opaque structure that keeps the whole state of a Lua interpreter.
+The Lua library is fully reentrant:
+it has no global variables.
+All information about a state is kept in this structure.
+
+
+<p>
+A pointer to this state must be passed as the first argument to
+every function in the library, except to <a href="#lua_newstate"><code>lua_newstate</code></a>,
+which creates a Lua state from scratch.
+
+
+
+
+
+<hr><h3><a name="lua_status"><code>lua_status</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_status (lua_State *L);</pre>
+
+<p>
+Returns the status of the thread <code>L</code>.
+
+
+<p>
+The status can be 0 for a normal thread,
+an error code if the thread finished its execution with an error,
+or <a name="pdf-LUA_YIELD"><code>LUA_YIELD</code></a> if the thread is suspended.
+
+
+
+
+
+<hr><h3><a name="lua_toboolean"><code>lua_toboolean</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_toboolean (lua_State *L, int index);</pre>
+
+<p>
+Converts the Lua value at the given acceptable index to a C&nbsp;boolean
+value (0&nbsp;or&nbsp;1).
+Like all tests in Lua,
+<a href="#lua_toboolean"><code>lua_toboolean</code></a> returns 1 for any Lua value
+different from <b>false</b> and <b>nil</b>;
+otherwise it returns 0.
+It also returns 0 when called with a non-valid index.
+(If you want to accept only actual boolean values,
+use <a href="#lua_isboolean"><code>lua_isboolean</code></a> to test the value's type.)
+
+
+
+
+
+<hr><h3><a name="lua_tocfunction"><code>lua_tocfunction</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>lua_CFunction lua_tocfunction (lua_State *L, int index);</pre>
+
+<p>
+Converts a value at the given acceptable index to a C&nbsp;function.
+That value must be a C&nbsp;function;
+otherwise, returns <code>NULL</code>.
+
+
+
+
+
+<hr><h3><a name="lua_tointeger"><code>lua_tointeger</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>lua_Integer lua_tointeger (lua_State *L, int index);</pre>
+
+<p>
+Converts the Lua value at the given acceptable index
+to the signed integral type <a href="#lua_Integer"><code>lua_Integer</code></a>.
+The Lua value must be a number or a string convertible to a number
+(see <a href="#2.2.1">&sect;2.2.1</a>);
+otherwise, <a href="#lua_tointeger"><code>lua_tointeger</code></a> returns&nbsp;0.
+
+
+<p>
+If the number is not an integer,
+it is truncated in some non-specified way.
+
+
+
+
+
+<hr><h3><a name="lua_tolstring"><code>lua_tolstring</code></a></h3><p>
+<span class="apii">[-0, +0, <em>m</em>]</span>
+<pre>const char *lua_tolstring (lua_State *L, int index, size_t *len);</pre>
+
+<p>
+Converts the Lua value at the given acceptable index to a C&nbsp;string.
+If <code>len</code> is not <code>NULL</code>,
+it also sets <code>*len</code> with the string length.
+The Lua value must be a string or a number;
+otherwise, the function returns <code>NULL</code>.
+If the value is a number,
+then <a href="#lua_tolstring"><code>lua_tolstring</code></a> also
+<em>changes the actual value in the stack to a string</em>.
+(This change confuses <a href="#lua_next"><code>lua_next</code></a>
+when <a href="#lua_tolstring"><code>lua_tolstring</code></a> is applied to keys during a table traversal.)
+
+
+<p>
+<a href="#lua_tolstring"><code>lua_tolstring</code></a> returns a fully aligned pointer
+to a string inside the Lua state.
+This string always has a zero ('<code>\0</code>')
+after its last character (as in&nbsp;C),
+but may contain other zeros in its body.
+Because Lua has garbage collection,
+there is no guarantee that the pointer returned by <a href="#lua_tolstring"><code>lua_tolstring</code></a>
+will be valid after the corresponding value is removed from the stack.
+
+
+
+
+
+<hr><h3><a name="lua_tonumber"><code>lua_tonumber</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>lua_Number lua_tonumber (lua_State *L, int index);</pre>
+
+<p>
+Converts the Lua value at the given acceptable index
+to the C&nbsp;type <a href="#lua_Number"><code>lua_Number</code></a> (see <a href="#lua_Number"><code>lua_Number</code></a>).
+The Lua value must be a number or a string convertible to a number
+(see <a href="#2.2.1">&sect;2.2.1</a>);
+otherwise, <a href="#lua_tonumber"><code>lua_tonumber</code></a> returns&nbsp;0.
+
+
+
+
+
+<hr><h3><a name="lua_topointer"><code>lua_topointer</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>const void *lua_topointer (lua_State *L, int index);</pre>
+
+<p>
+Converts the value at the given acceptable index to a generic
+C&nbsp;pointer (<code>void*</code>).
+The value may be a userdata, a table, a thread, or a function;
+otherwise, <a href="#lua_topointer"><code>lua_topointer</code></a> returns <code>NULL</code>.
+Different objects will give different pointers.
+There is no way to convert the pointer back to its original value.
+
+
+<p>
+Typically this function is used only for debug information.
+
+
+
+
+
+<hr><h3><a name="lua_tostring"><code>lua_tostring</code></a></h3><p>
+<span class="apii">[-0, +0, <em>m</em>]</span>
+<pre>const char *lua_tostring (lua_State *L, int index);</pre>
+
+<p>
+Equivalent to <a href="#lua_tolstring"><code>lua_tolstring</code></a> with <code>len</code> equal to <code>NULL</code>.
+
+
+
+
+
+<hr><h3><a name="lua_tothread"><code>lua_tothread</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>lua_State *lua_tothread (lua_State *L, int index);</pre>
+
+<p>
+Converts the value at the given acceptable index to a Lua thread
+(represented as <code>lua_State*</code>).
+This value must be a thread;
+otherwise, the function returns <code>NULL</code>.
+
+
+
+
+
+<hr><h3><a name="lua_touserdata"><code>lua_touserdata</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>void *lua_touserdata (lua_State *L, int index);</pre>
+
+<p>
+If the value at the given acceptable index is a full userdata,
+returns its block address.
+If the value is a light userdata,
+returns its pointer.
+Otherwise, returns <code>NULL</code>.
+
+
+
+
+
+<hr><h3><a name="lua_type"><code>lua_type</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_type (lua_State *L, int index);</pre>
+
+<p>
+Returns the type of the value in the given acceptable index,
+or <code>LUA_TNONE</code> for a non-valid index
+(that is, an index to an "empty" stack position).
+The types returned by <a href="#lua_type"><code>lua_type</code></a> are coded by the following constants
+defined in <code>lua.h</code>:
+<code>LUA_TNIL</code>,
+<code>LUA_TNUMBER</code>,
+<code>LUA_TBOOLEAN</code>,
+<code>LUA_TSTRING</code>,
+<code>LUA_TTABLE</code>,
+<code>LUA_TFUNCTION</code>,
+<code>LUA_TUSERDATA</code>,
+<code>LUA_TTHREAD</code>,
+and
+<code>LUA_TLIGHTUSERDATA</code>.
+
+
+
+
+
+<hr><h3><a name="lua_typename"><code>lua_typename</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>const char *lua_typename  (lua_State *L, int tp);</pre>
+
+<p>
+Returns the name of the type encoded by the value <code>tp</code>,
+which must be one the values returned by <a href="#lua_type"><code>lua_type</code></a>.
+
+
+
+
+
+<hr><h3><a name="lua_Writer"><code>lua_Writer</code></a></h3>
+<pre>typedef int (*lua_Writer) (lua_State *L,
+                           const void* p,
+                           size_t sz,
+                           void* ud);</pre>
+
+<p>
+The type of the writer function used by <a href="#lua_dump"><code>lua_dump</code></a>.
+Every time it produces another piece of chunk,
+<a href="#lua_dump"><code>lua_dump</code></a> calls the writer,
+passing along the buffer to be written (<code>p</code>),
+its size (<code>sz</code>),
+and the <code>data</code> parameter supplied to <a href="#lua_dump"><code>lua_dump</code></a>.
+
+
+<p>
+The writer returns an error code:
+0&nbsp;means no errors;
+any other value means an error and stops <a href="#lua_dump"><code>lua_dump</code></a> from
+calling the writer again.
+
+
+
+
+
+<hr><h3><a name="lua_xmove"><code>lua_xmove</code></a></h3><p>
+<span class="apii">[-?, +?, <em>-</em>]</span>
+<pre>void lua_xmove (lua_State *from, lua_State *to, int n);</pre>
+
+<p>
+Exchange values between different threads of the <em>same</em> global state.
+
+
+<p>
+This function pops <code>n</code> values from the stack <code>from</code>,
+and pushes them onto the stack <code>to</code>.
+
+
+
+
+
+<hr><h3><a name="lua_yield"><code>lua_yield</code></a></h3><p>
+<span class="apii">[-?, +?, <em>-</em>]</span>
+<pre>int lua_yield  (lua_State *L, int nresults);</pre>
+
+<p>
+Yields a coroutine.
+
+
+<p>
+This function should only be called as the
+return expression of a C&nbsp;function, as follows:
+
+<pre>
+     return lua_yield (L, nresults);
+</pre><p>
+When a C&nbsp;function calls <a href="#lua_yield"><code>lua_yield</code></a> in that way,
+the running coroutine suspends its execution,
+and the call to <a href="#lua_resume"><code>lua_resume</code></a> that started this coroutine returns.
+The parameter <code>nresults</code> is the number of values from the stack
+that are passed as results to <a href="#lua_resume"><code>lua_resume</code></a>.
+
+
+
+
+
+
+
+<h2>3.8 - <a name="3.8">The Debug Interface</a></h2>
+
+<p>
+Lua has no built-in debugging facilities.
+Instead, it offers a special interface
+by means of functions and <em>hooks</em>.
+This interface allows the construction of different
+kinds of debuggers, profilers, and other tools
+that need "inside information" from the interpreter.
+
+
+
+<hr><h3><a name="lua_Debug"><code>lua_Debug</code></a></h3>
+<pre>typedef struct lua_Debug {
+  int event;
+  const char *name;           /* (n) */
+  const char *namewhat;       /* (n) */
+  const char *what;           /* (S) */
+  const char *source;         /* (S) */
+  int currentline;            /* (l) */
+  int nups;                   /* (u) number of upvalues */
+  int linedefined;            /* (S) */
+  int lastlinedefined;        /* (S) */
+  char short_src[LUA_IDSIZE]; /* (S) */
+  /* private part */
+  <em>other fields</em>
+} lua_Debug;</pre>
+
+<p>
+A structure used to carry different pieces of
+information about an active function.
+<a href="#lua_getstack"><code>lua_getstack</code></a> fills only the private part
+of this structure, for later use.
+To fill the other fields of <a href="#lua_Debug"><code>lua_Debug</code></a> with useful information,
+call <a href="#lua_getinfo"><code>lua_getinfo</code></a>.
+
+
+<p>
+The fields of <a href="#lua_Debug"><code>lua_Debug</code></a> have the following meaning:
+
+<ul>
+
+<li><b><code>source</code>:</b>
+If the function was defined in a string,
+then <code>source</code> is that string.
+If the function was defined in a file,
+then <code>source</code> starts with a '<code>@</code>' followed by the file name.
+</li>
+
+<li><b><code>short_src</code>:</b>
+a "printable" version of <code>source</code>, to be used in error messages.
+</li>
+
+<li><b><code>linedefined</code>:</b>
+the line number where the definition of the function starts.
+</li>
+
+<li><b><code>lastlinedefined</code>:</b>
+the line number where the definition of the function ends.
+</li>
+
+<li><b><code>what</code>:</b>
+the string <code>"Lua"</code> if the function is a Lua function,
+<code>"C"</code> if it is a C&nbsp;function,
+<code>"main"</code> if it is the main part of a chunk,
+and <code>"tail"</code> if it was a function that did a tail call.
+In the latter case,
+Lua has no other information about the function.
+</li>
+
+<li><b><code>currentline</code>:</b>
+the current line where the given function is executing.
+When no line information is available,
+<code>currentline</code> is set to -1.
+</li>
+
+<li><b><code>name</code>:</b>
+a reasonable name for the given function.
+Because functions in Lua are first-class values,
+they do not have a fixed name:
+some functions may be the value of multiple global variables,
+while others may be stored only in a table field.
+The <code>lua_getinfo</code> function checks how the function was
+called to find a suitable name.
+If it cannot find a name,
+then <code>name</code> is set to <code>NULL</code>.
+</li>
+
+<li><b><code>namewhat</code>:</b>
+explains the <code>name</code> field.
+The value of <code>namewhat</code> can be
+<code>"global"</code>, <code>"local"</code>, <code>"method"</code>,
+<code>"field"</code>, <code>"upvalue"</code>, or <code>""</code> (the empty string),
+according to how the function was called.
+(Lua uses the empty string when no other option seems to apply.)
+</li>
+
+<li><b><code>nups</code>:</b>
+the number of upvalues of the function.
+</li>
+
+</ul>
+
+
+
+
+<hr><h3><a name="lua_gethook"><code>lua_gethook</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>lua_Hook lua_gethook (lua_State *L);</pre>
+
+<p>
+Returns the current hook function.
+
+
+
+
+
+<hr><h3><a name="lua_gethookcount"><code>lua_gethookcount</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_gethookcount (lua_State *L);</pre>
+
+<p>
+Returns the current hook count.
+
+
+
+
+
+<hr><h3><a name="lua_gethookmask"><code>lua_gethookmask</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_gethookmask (lua_State *L);</pre>
+
+<p>
+Returns the current hook mask.
+
+
+
+
+
+<hr><h3><a name="lua_getinfo"><code>lua_getinfo</code></a></h3><p>
+<span class="apii">[-(0|1), +(0|1|2), <em>m</em>]</span>
+<pre>int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar);</pre>
+
+<p>
+Returns information about a specific function or function invocation.
+
+
+<p>
+To get information about a function invocation,
+the parameter <code>ar</code> must be a valid activation record that was
+filled by a previous call to <a href="#lua_getstack"><code>lua_getstack</code></a> or
+given as argument to a hook (see <a href="#lua_Hook"><code>lua_Hook</code></a>).
+
+
+<p>
+To get information about a function you push it onto the stack
+and start the <code>what</code> string with the character '<code>&gt;</code>'.
+(In that case,
+<code>lua_getinfo</code> pops the function in the top of the stack.)
+For instance, to know in which line a function <code>f</code> was defined,
+you can write the following code:
+
+<pre>
+     lua_Debug ar;
+     lua_getfield(L, LUA_GLOBALSINDEX, "f");  /* get global 'f' */
+     lua_getinfo(L, "&gt;S", &amp;ar);
+     printf("%d\n", ar.linedefined);
+</pre>
+
+<p>
+Each character in the string <code>what</code>
+selects some fields of the structure <code>ar</code> to be filled or
+a value to be pushed on the stack:
+
+<ul>
+
+<li><b>'<code>n</code>':</b> fills in the field <code>name</code> and <code>namewhat</code>;
+</li>
+
+<li><b>'<code>S</code>':</b>
+fills in the fields <code>source</code>, <code>short_src</code>,
+<code>linedefined</code>, <code>lastlinedefined</code>, and <code>what</code>;
+</li>
+
+<li><b>'<code>l</code>':</b> fills in the field <code>currentline</code>;
+</li>
+
+<li><b>'<code>u</code>':</b> fills in the field <code>nups</code>;
+</li>
+
+<li><b>'<code>f</code>':</b>
+pushes onto the stack the function that is
+running at the given level;
+</li>
+
+<li><b>'<code>L</code>':</b>
+pushes onto the stack a table whose indices are the
+numbers of the lines that are valid on the function.
+(A <em>valid line</em> is a line with some associated code,
+that is, a line where you can put a break point.
+Non-valid lines include empty lines and comments.)
+</li>
+
+</ul>
+
+<p>
+This function returns 0 on error
+(for instance, an invalid option in <code>what</code>).
+
+
+
+
+
+<hr><h3><a name="lua_getlocal"><code>lua_getlocal</code></a></h3><p>
+<span class="apii">[-0, +(0|1), <em>-</em>]</span>
+<pre>const char *lua_getlocal (lua_State *L, lua_Debug *ar, int n);</pre>
+
+<p>
+Gets information about a local variable of a given activation record.
+The parameter <code>ar</code> must be a valid activation record that was
+filled by a previous call to <a href="#lua_getstack"><code>lua_getstack</code></a> or
+given as argument to a hook (see <a href="#lua_Hook"><code>lua_Hook</code></a>).
+The index <code>n</code> selects which local variable to inspect
+(1 is the first parameter or active local variable, and so on,
+until the last active local variable).
+<a href="#lua_getlocal"><code>lua_getlocal</code></a> pushes the variable's value onto the stack
+and returns its name.
+
+
+<p>
+Variable names starting with '<code>(</code>' (open parentheses)
+represent internal variables
+(loop control variables, temporaries, and C&nbsp;function locals).
+
+
+<p>
+Returns <code>NULL</code> (and pushes nothing)
+when the index is greater than
+the number of active local variables.
+
+
+
+
+
+<hr><h3><a name="lua_getstack"><code>lua_getstack</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_getstack (lua_State *L, int level, lua_Debug *ar);</pre>
+
+<p>
+Get information about the interpreter runtime stack.
+
+
+<p>
+This function fills parts of a <a href="#lua_Debug"><code>lua_Debug</code></a> structure with
+an identification of the <em>activation record</em>
+of the function executing at a given level.
+Level&nbsp;0 is the current running function,
+whereas level <em>n+1</em> is the function that has called level <em>n</em>.
+When there are no errors, <a href="#lua_getstack"><code>lua_getstack</code></a> returns 1;
+when called with a level greater than the stack depth,
+it returns 0.
+
+
+
+
+
+<hr><h3><a name="lua_getupvalue"><code>lua_getupvalue</code></a></h3><p>
+<span class="apii">[-0, +(0|1), <em>-</em>]</span>
+<pre>const char *lua_getupvalue (lua_State *L, int funcindex, int n);</pre>
+
+<p>
+Gets information about a closure's upvalue.
+(For Lua functions,
+upvalues are the external local variables that the function uses,
+and that are consequently included in its closure.)
+<a href="#lua_getupvalue"><code>lua_getupvalue</code></a> gets the index <code>n</code> of an upvalue,
+pushes the upvalue's value onto the stack,
+and returns its name.
+<code>funcindex</code> points to the closure in the stack.
+(Upvalues have no particular order,
+as they are active through the whole function.
+So, they are numbered in an arbitrary order.)
+
+
+<p>
+Returns <code>NULL</code> (and pushes nothing)
+when the index is greater than the number of upvalues.
+For C&nbsp;functions, this function uses the empty string <code>""</code>
+as a name for all upvalues.
+
+
+
+
+
+<hr><h3><a name="lua_Hook"><code>lua_Hook</code></a></h3>
+<pre>typedef void (*lua_Hook) (lua_State *L, lua_Debug *ar);</pre>
+
+<p>
+Type for debugging hook functions.
+
+
+<p>
+Whenever a hook is called, its <code>ar</code> argument has its field
+<code>event</code> set to the specific event that triggered the hook.
+Lua identifies these events with the following constants:
+<a name="pdf-LUA_HOOKCALL"><code>LUA_HOOKCALL</code></a>, <a name="pdf-LUA_HOOKRET"><code>LUA_HOOKRET</code></a>,
+<a name="pdf-LUA_HOOKTAILRET"><code>LUA_HOOKTAILRET</code></a>, <a name="pdf-LUA_HOOKLINE"><code>LUA_HOOKLINE</code></a>,
+and <a name="pdf-LUA_HOOKCOUNT"><code>LUA_HOOKCOUNT</code></a>.
+Moreover, for line events, the field <code>currentline</code> is also set.
+To get the value of any other field in <code>ar</code>,
+the hook must call <a href="#lua_getinfo"><code>lua_getinfo</code></a>.
+For return events, <code>event</code> may be <code>LUA_HOOKRET</code>,
+the normal value, or <code>LUA_HOOKTAILRET</code>.
+In the latter case, Lua is simulating a return from
+a function that did a tail call;
+in this case, it is useless to call <a href="#lua_getinfo"><code>lua_getinfo</code></a>.
+
+
+<p>
+While Lua is running a hook, it disables other calls to hooks.
+Therefore, if a hook calls back Lua to execute a function or a chunk,
+this execution occurs without any calls to hooks.
+
+
+
+
+
+<hr><h3><a name="lua_sethook"><code>lua_sethook</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_sethook (lua_State *L, lua_Hook f, int mask, int count);</pre>
+
+<p>
+Sets the debugging hook function.
+
+
+<p>
+Argument <code>f</code> is the hook function.
+<code>mask</code> specifies on which events the hook will be called:
+it is formed by a bitwise or of the constants
+<a name="pdf-LUA_MASKCALL"><code>LUA_MASKCALL</code></a>,
+<a name="pdf-LUA_MASKRET"><code>LUA_MASKRET</code></a>,
+<a name="pdf-LUA_MASKLINE"><code>LUA_MASKLINE</code></a>,
+and <a name="pdf-LUA_MASKCOUNT"><code>LUA_MASKCOUNT</code></a>.
+The <code>count</code> argument is only meaningful when the mask
+includes <code>LUA_MASKCOUNT</code>.
+For each event, the hook is called as explained below:
+
+<ul>
+
+<li><b>The call hook:</b> is called when the interpreter calls a function.
+The hook is called just after Lua enters the new function,
+before the function gets its arguments.
+</li>
+
+<li><b>The return hook:</b> is called when the interpreter returns from a function.
+The hook is called just before Lua leaves the function.
+You have no access to the values to be returned by the function.
+</li>
+
+<li><b>The line hook:</b> is called when the interpreter is about to
+start the execution of a new line of code,
+or when it jumps back in the code (even to the same line).
+(This event only happens while Lua is executing a Lua function.)
+</li>
+
+<li><b>The count hook:</b> is called after the interpreter executes every
+<code>count</code> instructions.
+(This event only happens while Lua is executing a Lua function.)
+</li>
+
+</ul>
+
+<p>
+A hook is disabled by setting <code>mask</code> to zero.
+
+
+
+
+
+<hr><h3><a name="lua_setlocal"><code>lua_setlocal</code></a></h3><p>
+<span class="apii">[-(0|1), +0, <em>-</em>]</span>
+<pre>const char *lua_setlocal (lua_State *L, lua_Debug *ar, int n);</pre>
+
+<p>
+Sets the value of a local variable of a given activation record.
+Parameters <code>ar</code> and <code>n</code> are as in <a href="#lua_getlocal"><code>lua_getlocal</code></a>
+(see <a href="#lua_getlocal"><code>lua_getlocal</code></a>).
+<a href="#lua_setlocal"><code>lua_setlocal</code></a> assigns the value at the top of the stack
+to the variable and returns its name.
+It also pops the value from the stack.
+
+
+<p>
+Returns <code>NULL</code> (and pops nothing)
+when the index is greater than
+the number of active local variables.
+
+
+
+
+
+<hr><h3><a name="lua_setupvalue"><code>lua_setupvalue</code></a></h3><p>
+<span class="apii">[-(0|1), +0, <em>-</em>]</span>
+<pre>const char *lua_setupvalue (lua_State *L, int funcindex, int n);</pre>
+
+<p>
+Sets the value of a closure's upvalue.
+It assigns the value at the top of the stack
+to the upvalue and returns its name.
+It also pops the value from the stack.
+Parameters <code>funcindex</code> and <code>n</code> are as in the <a href="#lua_getupvalue"><code>lua_getupvalue</code></a>
+(see <a href="#lua_getupvalue"><code>lua_getupvalue</code></a>).
+
+
+<p>
+Returns <code>NULL</code> (and pops nothing)
+when the index is greater than the number of upvalues.
+
+
+
+
+
+
+
+<h1>4 - <a name="4">The Auxiliary Library</a></h1>
+
+<p>
+
+The <em>auxiliary library</em> provides several convenient functions
+to interface C with Lua.
+While the basic API provides the primitive functions for all 
+interactions between C and Lua,
+the auxiliary library provides higher-level functions for some
+common tasks.
+
+
+<p>
+All functions from the auxiliary library
+are defined in header file <code>lauxlib.h</code> and
+have a prefix <code>luaL_</code>.
+
+
+<p>
+All functions in the auxiliary library are built on
+top of the basic API,
+and so they provide nothing that cannot be done with this API.
+
+
+<p>
+Several functions in the auxiliary library are used to
+check C&nbsp;function arguments.
+Their names are always <code>luaL_check*</code> or <code>luaL_opt*</code>.
+All of these functions throw an error if the check is not satisfied.
+Because the error message is formatted for arguments
+(e.g., "<code>bad argument #1</code>"),
+you should not use these functions for other stack values.
+
+
+
+<h2>4.1 - <a name="4.1">Functions and Types</a></h2>
+
+<p>
+Here we list all functions and types from the auxiliary library
+in alphabetical order.
+
+
+
+<hr><h3><a name="luaL_addchar"><code>luaL_addchar</code></a></h3><p>
+<span class="apii">[-0, +0, <em>m</em>]</span>
+<pre>void luaL_addchar (luaL_Buffer *B, char c);</pre>
+
+<p>
+Adds the character <code>c</code> to the buffer <code>B</code>
+(see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>).
+
+
+
+
+
+<hr><h3><a name="luaL_addlstring"><code>luaL_addlstring</code></a></h3><p>
+<span class="apii">[-0, +0, <em>m</em>]</span>
+<pre>void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l);</pre>
+
+<p>
+Adds the string pointed to by <code>s</code> with length <code>l</code> to
+the buffer <code>B</code>
+(see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>).
+The string may contain embedded zeros.
+
+
+
+
+
+<hr><h3><a name="luaL_addsize"><code>luaL_addsize</code></a></h3><p>
+<span class="apii">[-0, +0, <em>m</em>]</span>
+<pre>void luaL_addsize (luaL_Buffer *B, size_t n);</pre>
+
+<p>
+Adds to the buffer <code>B</code> (see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>)
+a string of length <code>n</code> previously copied to the
+buffer area (see <a href="#luaL_prepbuffer"><code>luaL_prepbuffer</code></a>).
+
+
+
+
+
+<hr><h3><a name="luaL_addstring"><code>luaL_addstring</code></a></h3><p>
+<span class="apii">[-0, +0, <em>m</em>]</span>
+<pre>void luaL_addstring (luaL_Buffer *B, const char *s);</pre>
+
+<p>
+Adds the zero-terminated string pointed to by <code>s</code>
+to the buffer <code>B</code>
+(see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>).
+The string may not contain embedded zeros.
+
+
+
+
+
+<hr><h3><a name="luaL_addvalue"><code>luaL_addvalue</code></a></h3><p>
+<span class="apii">[-1, +0, <em>m</em>]</span>
+<pre>void luaL_addvalue (luaL_Buffer *B);</pre>
+
+<p>
+Adds the value at the top of the stack
+to the buffer <code>B</code>
+(see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>).
+Pops the value.
+
+
+<p>
+This is the only function on string buffers that can (and must)
+be called with an extra element on the stack,
+which is the value to be added to the buffer.
+
+
+
+
+
+<hr><h3><a name="luaL_argcheck"><code>luaL_argcheck</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>void luaL_argcheck (lua_State *L,
+                    int cond,
+                    int narg,
+                    const char *extramsg);</pre>
+
+<p>
+Checks whether <code>cond</code> is true.
+If not, raises an error with the following message,
+where <code>func</code> is retrieved from the call stack:
+
+<pre>
+     bad argument #&lt;narg&gt; to &lt;func&gt; (&lt;extramsg&gt;)
+</pre>
+
+
+
+
+<hr><h3><a name="luaL_argerror"><code>luaL_argerror</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>int luaL_argerror (lua_State *L, int narg, const char *extramsg);</pre>
+
+<p>
+Raises an error with the following message,
+where <code>func</code> is retrieved from the call stack:
+
+<pre>
+     bad argument #&lt;narg&gt; to &lt;func&gt; (&lt;extramsg&gt;)
+</pre>
+
+<p>
+This function never returns,
+but it is an idiom to use it in C&nbsp;functions
+as <code>return luaL_argerror(<em>args</em>)</code>.
+
+
+
+
+
+<hr><h3><a name="luaL_Buffer"><code>luaL_Buffer</code></a></h3>
+<pre>typedef struct luaL_Buffer luaL_Buffer;</pre>
+
+<p>
+Type for a <em>string buffer</em>.
+
+
+<p>
+A string buffer allows C&nbsp;code to build Lua strings piecemeal.
+Its pattern of use is as follows:
+
+<ul>
+
+<li>First you declare a variable <code>b</code> of type <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>.</li>
+
+<li>Then you initialize it with a call <code>luaL_buffinit(L, &amp;b)</code>.</li>
+
+<li>
+Then you add string pieces to the buffer calling any of
+the <code>luaL_add*</code> functions.
+</li>
+
+<li>
+You finish by calling <code>luaL_pushresult(&amp;b)</code>.
+This call leaves the final string on the top of the stack.
+</li>
+
+</ul>
+
+<p>
+During its normal operation,
+a string buffer uses a variable number of stack slots.
+So, while using a buffer, you cannot assume that you know where
+the top of the stack is.
+You can use the stack between successive calls to buffer operations
+as long as that use is balanced;
+that is,
+when you call a buffer operation,
+the stack is at the same level
+it was immediately after the previous buffer operation.
+(The only exception to this rule is <a href="#luaL_addvalue"><code>luaL_addvalue</code></a>.)
+After calling <a href="#luaL_pushresult"><code>luaL_pushresult</code></a> the stack is back to its
+level when the buffer was initialized,
+plus the final string on its top.
+
+
+
+
+
+<hr><h3><a name="luaL_buffinit"><code>luaL_buffinit</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>void luaL_buffinit (lua_State *L, luaL_Buffer *B);</pre>
+
+<p>
+Initializes a buffer <code>B</code>.
+This function does not allocate any space;
+the buffer must be declared as a variable
+(see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>).
+
+
+
+
+
+<hr><h3><a name="luaL_callmeta"><code>luaL_callmeta</code></a></h3><p>
+<span class="apii">[-0, +(0|1), <em>e</em>]</span>
+<pre>int luaL_callmeta (lua_State *L, int obj, const char *e);</pre>
+
+<p>
+Calls a metamethod.
+
+
+<p>
+If the object at index <code>obj</code> has a metatable and this
+metatable has a field <code>e</code>,
+this function calls this field and passes the object as its only argument.
+In this case this function returns 1 and pushes onto the
+stack the value returned by the call.
+If there is no metatable or no metamethod,
+this function returns 0 (without pushing any value on the stack).
+
+
+
+
+
+<hr><h3><a name="luaL_checkany"><code>luaL_checkany</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>void luaL_checkany (lua_State *L, int narg);</pre>
+
+<p>
+Checks whether the function has an argument
+of any type (including <b>nil</b>) at position <code>narg</code>.
+
+
+
+
+
+<hr><h3><a name="luaL_checkint"><code>luaL_checkint</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>int luaL_checkint (lua_State *L, int narg);</pre>
+
+<p>
+Checks whether the function argument <code>narg</code> is a number
+and returns this number cast to an <code>int</code>.
+
+
+
+
+
+<hr><h3><a name="luaL_checkinteger"><code>luaL_checkinteger</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>lua_Integer luaL_checkinteger (lua_State *L, int narg);</pre>
+
+<p>
+Checks whether the function argument <code>narg</code> is a number
+and returns this number cast to a <a href="#lua_Integer"><code>lua_Integer</code></a>.
+
+
+
+
+
+<hr><h3><a name="luaL_checklong"><code>luaL_checklong</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>long luaL_checklong (lua_State *L, int narg);</pre>
+
+<p>
+Checks whether the function argument <code>narg</code> is a number
+and returns this number cast to a <code>long</code>.
+
+
+
+
+
+<hr><h3><a name="luaL_checklstring"><code>luaL_checklstring</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>const char *luaL_checklstring (lua_State *L, int narg, size_t *l);</pre>
+
+<p>
+Checks whether the function argument <code>narg</code> is a string
+and returns this string;
+if <code>l</code> is not <code>NULL</code> fills <code>*l</code>
+with the string's length.
+
+
+<p>
+This function uses <a href="#lua_tolstring"><code>lua_tolstring</code></a> to get its result,
+so all conversions and caveats of that function apply here.
+
+
+
+
+
+<hr><h3><a name="luaL_checknumber"><code>luaL_checknumber</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>lua_Number luaL_checknumber (lua_State *L, int narg);</pre>
+
+<p>
+Checks whether the function argument <code>narg</code> is a number
+and returns this number.
+
+
+
+
+
+<hr><h3><a name="luaL_checkoption"><code>luaL_checkoption</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>int luaL_checkoption (lua_State *L,
+                      int narg,
+                      const char *def,
+                      const char *const lst[]);</pre>
+
+<p>
+Checks whether the function argument <code>narg</code> is a string and
+searches for this string in the array <code>lst</code>
+(which must be NULL-terminated).
+Returns the index in the array where the string was found.
+Raises an error if the argument is not a string or
+if the string cannot be found.
+
+
+<p>
+If <code>def</code> is not <code>NULL</code>,
+the function uses <code>def</code> as a default value when
+there is no argument <code>narg</code> or if this argument is <b>nil</b>.
+
+
+<p>
+This is a useful function for mapping strings to C&nbsp;enums.
+(The usual convention in Lua libraries is
+to use strings instead of numbers to select options.)
+
+
+
+
+
+<hr><h3><a name="luaL_checkstack"><code>luaL_checkstack</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>void luaL_checkstack (lua_State *L, int sz, const char *msg);</pre>
+
+<p>
+Grows the stack size to <code>top + sz</code> elements,
+raising an error if the stack cannot grow to that size.
+<code>msg</code> is an additional text to go into the error message.
+
+
+
+
+
+<hr><h3><a name="luaL_checkstring"><code>luaL_checkstring</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>const char *luaL_checkstring (lua_State *L, int narg);</pre>
+
+<p>
+Checks whether the function argument <code>narg</code> is a string
+and returns this string.
+
+
+<p>
+This function uses <a href="#lua_tolstring"><code>lua_tolstring</code></a> to get its result,
+so all conversions and caveats of that function apply here.
+
+
+
+
+
+<hr><h3><a name="luaL_checktype"><code>luaL_checktype</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>void luaL_checktype (lua_State *L, int narg, int t);</pre>
+
+<p>
+Checks whether the function argument <code>narg</code> has type <code>t</code>.
+See <a href="#lua_type"><code>lua_type</code></a> for the encoding of types for <code>t</code>.
+
+
+
+
+
+<hr><h3><a name="luaL_checkudata"><code>luaL_checkudata</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>void *luaL_checkudata (lua_State *L, int narg, const char *tname);</pre>
+
+<p>
+Checks whether the function argument <code>narg</code> is a userdata
+of the type <code>tname</code> (see <a href="#luaL_newmetatable"><code>luaL_newmetatable</code></a>).
+
+
+
+
+
+<hr><h3><a name="luaL_dofile"><code>luaL_dofile</code></a></h3><p>
+<span class="apii">[-0, +?, <em>m</em>]</span>
+<pre>int luaL_dofile (lua_State *L, const char *filename);</pre>
+
+<p>
+Loads and runs the given file.
+It is defined as the following macro:
+
+<pre>
+     (luaL_loadfile(L, filename) || lua_pcall(L, 0, LUA_MULTRET, 0))
+</pre><p>
+It returns 0 if there are no errors
+or 1 in case of errors.
+
+
+
+
+
+<hr><h3><a name="luaL_dostring"><code>luaL_dostring</code></a></h3><p>
+<span class="apii">[-0, +?, <em>m</em>]</span>
+<pre>int luaL_dostring (lua_State *L, const char *str);</pre>
+
+<p>
+Loads and runs the given string.
+It is defined as the following macro:
+
+<pre>
+     (luaL_loadstring(L, str) || lua_pcall(L, 0, LUA_MULTRET, 0))
+</pre><p>
+It returns 0 if there are no errors
+or 1 in case of errors.
+
+
+
+
+
+<hr><h3><a name="luaL_error"><code>luaL_error</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>int luaL_error (lua_State *L, const char *fmt, ...);</pre>
+
+<p>
+Raises an error.
+The error message format is given by <code>fmt</code>
+plus any extra arguments,
+following the same rules of <a href="#lua_pushfstring"><code>lua_pushfstring</code></a>.
+It also adds at the beginning of the message the file name and
+the line number where the error occurred,
+if this information is available.
+
+
+<p>
+This function never returns,
+but it is an idiom to use it in C&nbsp;functions
+as <code>return luaL_error(<em>args</em>)</code>.
+
+
+
+
+
+<hr><h3><a name="luaL_getmetafield"><code>luaL_getmetafield</code></a></h3><p>
+<span class="apii">[-0, +(0|1), <em>m</em>]</span>
+<pre>int luaL_getmetafield (lua_State *L, int obj, const char *e);</pre>
+
+<p>
+Pushes onto the stack the field <code>e</code> from the metatable
+of the object at index <code>obj</code>.
+If the object does not have a metatable,
+or if the metatable does not have this field,
+returns 0 and pushes nothing.
+
+
+
+
+
+<hr><h3><a name="luaL_getmetatable"><code>luaL_getmetatable</code></a></h3><p>
+<span class="apii">[-0, +1, <em>-</em>]</span>
+<pre>void luaL_getmetatable (lua_State *L, const char *tname);</pre>
+
+<p>
+Pushes onto the stack the metatable associated with name <code>tname</code>
+in the registry (see <a href="#luaL_newmetatable"><code>luaL_newmetatable</code></a>).
+
+
+
+
+
+<hr><h3><a name="luaL_gsub"><code>luaL_gsub</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>const char *luaL_gsub (lua_State *L,
+                       const char *s,
+                       const char *p,
+                       const char *r);</pre>
+
+<p>
+Creates a copy of string <code>s</code> by replacing
+any occurrence of the string <code>p</code>
+with the string <code>r</code>.
+Pushes the resulting string on the stack and returns it.
+
+
+
+
+
+<hr><h3><a name="luaL_loadbuffer"><code>luaL_loadbuffer</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>int luaL_loadbuffer (lua_State *L,
+                     const char *buff,
+                     size_t sz,
+                     const char *name);</pre>
+
+<p>
+Loads a buffer as a Lua chunk.
+This function uses <a href="#lua_load"><code>lua_load</code></a> to load the chunk in the
+buffer pointed to by <code>buff</code> with size <code>sz</code>.
+
+
+<p>
+This function returns the same results as <a href="#lua_load"><code>lua_load</code></a>.
+<code>name</code> is the chunk name,
+used for debug information and error messages.
+
+
+
+
+
+<hr><h3><a name="luaL_loadfile"><code>luaL_loadfile</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>int luaL_loadfile (lua_State *L, const char *filename);</pre>
+
+<p>
+Loads a file as a Lua chunk.
+This function uses <a href="#lua_load"><code>lua_load</code></a> to load the chunk in the file
+named <code>filename</code>.
+If <code>filename</code> is <code>NULL</code>,
+then it loads from the standard input.
+The first line in the file is ignored if it starts with a <code>#</code>.
+
+
+<p>
+This function returns the same results as <a href="#lua_load"><code>lua_load</code></a>,
+but it has an extra error code <a name="pdf-LUA_ERRFILE"><code>LUA_ERRFILE</code></a>
+if it cannot open/read the file.
+
+
+<p>
+As <a href="#lua_load"><code>lua_load</code></a>, this function only loads the chunk;
+it does not run it.
+
+
+
+
+
+<hr><h3><a name="luaL_loadstring"><code>luaL_loadstring</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>int luaL_loadstring (lua_State *L, const char *s);</pre>
+
+<p>
+Loads a string as a Lua chunk.
+This function uses <a href="#lua_load"><code>lua_load</code></a> to load the chunk in
+the zero-terminated string <code>s</code>.
+
+
+<p>
+This function returns the same results as <a href="#lua_load"><code>lua_load</code></a>.
+
+
+<p>
+Also as <a href="#lua_load"><code>lua_load</code></a>, this function only loads the chunk;
+it does not run it.
+
+
+
+
+
+<hr><h3><a name="luaL_newmetatable"><code>luaL_newmetatable</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>int luaL_newmetatable (lua_State *L, const char *tname);</pre>
+
+<p>
+If the registry already has the key <code>tname</code>,
+returns 0.
+Otherwise,
+creates a new table to be used as a metatable for userdata,
+adds it to the registry with key <code>tname</code>,
+and returns 1.
+
+
+<p>
+In both cases pushes onto the stack the final value associated
+with <code>tname</code> in the registry.
+
+
+
+
+
+<hr><h3><a name="luaL_newstate"><code>luaL_newstate</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>lua_State *luaL_newstate (void);</pre>
+
+<p>
+Creates a new Lua state.
+It calls <a href="#lua_newstate"><code>lua_newstate</code></a> with an
+allocator based on the standard&nbsp;C <code>realloc</code> function
+and then sets a panic function (see <a href="#lua_atpanic"><code>lua_atpanic</code></a>) that prints
+an error message to the standard error output in case of fatal
+errors.
+
+
+<p>
+Returns the new state,
+or <code>NULL</code> if there is a memory allocation error.
+
+
+
+
+
+<hr><h3><a name="luaL_openlibs"><code>luaL_openlibs</code></a></h3><p>
+<span class="apii">[-0, +0, <em>m</em>]</span>
+<pre>void luaL_openlibs (lua_State *L);</pre>
+
+<p>
+Opens all standard Lua libraries into the given state.
+
+
+
+
+
+<hr><h3><a name="luaL_optint"><code>luaL_optint</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>int luaL_optint (lua_State *L, int narg, int d);</pre>
+
+<p>
+If the function argument <code>narg</code> is a number,
+returns this number cast to an <code>int</code>.
+If this argument is absent or is <b>nil</b>,
+returns <code>d</code>.
+Otherwise, raises an error.
+
+
+
+
+
+<hr><h3><a name="luaL_optinteger"><code>luaL_optinteger</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>lua_Integer luaL_optinteger (lua_State *L,
+                             int narg,
+                             lua_Integer d);</pre>
+
+<p>
+If the function argument <code>narg</code> is a number,
+returns this number cast to a <a href="#lua_Integer"><code>lua_Integer</code></a>.
+If this argument is absent or is <b>nil</b>,
+returns <code>d</code>.
+Otherwise, raises an error.
+
+
+
+
+
+<hr><h3><a name="luaL_optlong"><code>luaL_optlong</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>long luaL_optlong (lua_State *L, int narg, long d);</pre>
+
+<p>
+If the function argument <code>narg</code> is a number,
+returns this number cast to a <code>long</code>.
+If this argument is absent or is <b>nil</b>,
+returns <code>d</code>.
+Otherwise, raises an error.
+
+
+
+
+
+<hr><h3><a name="luaL_optlstring"><code>luaL_optlstring</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>const char *luaL_optlstring (lua_State *L,
+                             int narg,
+                             const char *d,
+                             size_t *l);</pre>
+
+<p>
+If the function argument <code>narg</code> is a string,
+returns this string.
+If this argument is absent or is <b>nil</b>,
+returns <code>d</code>.
+Otherwise, raises an error.
+
+
+<p>
+If <code>l</code> is not <code>NULL</code>,
+fills the position <code>*l</code> with the results's length.
+
+
+
+
+
+<hr><h3><a name="luaL_optnumber"><code>luaL_optnumber</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>lua_Number luaL_optnumber (lua_State *L, int narg, lua_Number d);</pre>
+
+<p>
+If the function argument <code>narg</code> is a number,
+returns this number.
+If this argument is absent or is <b>nil</b>,
+returns <code>d</code>.
+Otherwise, raises an error.
+
+
+
+
+
+<hr><h3><a name="luaL_optstring"><code>luaL_optstring</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>const char *luaL_optstring (lua_State *L,
+                            int narg,
+                            const char *d);</pre>
+
+<p>
+If the function argument <code>narg</code> is a string,
+returns this string.
+If this argument is absent or is <b>nil</b>,
+returns <code>d</code>.
+Otherwise, raises an error.
+
+
+
+
+
+<hr><h3><a name="luaL_prepbuffer"><code>luaL_prepbuffer</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>char *luaL_prepbuffer (luaL_Buffer *B);</pre>
+
+<p>
+Returns an address to a space of size <a name="pdf-LUAL_BUFFERSIZE"><code>LUAL_BUFFERSIZE</code></a>
+where you can copy a string to be added to buffer <code>B</code>
+(see <a href="#luaL_Buffer"><code>luaL_Buffer</code></a>).
+After copying the string into this space you must call
+<a href="#luaL_addsize"><code>luaL_addsize</code></a> with the size of the string to actually add 
+it to the buffer.
+
+
+
+
+
+<hr><h3><a name="luaL_pushresult"><code>luaL_pushresult</code></a></h3><p>
+<span class="apii">[-?, +1, <em>m</em>]</span>
+<pre>void luaL_pushresult (luaL_Buffer *B);</pre>
+
+<p>
+Finishes the use of buffer <code>B</code> leaving the final string on
+the top of the stack.
+
+
+
+
+
+<hr><h3><a name="luaL_ref"><code>luaL_ref</code></a></h3><p>
+<span class="apii">[-1, +0, <em>m</em>]</span>
+<pre>int luaL_ref (lua_State *L, int t);</pre>
+
+<p>
+Creates and returns a <em>reference</em>,
+in the table at index <code>t</code>,
+for the object at the top of the stack (and pops the object).
+
+
+<p>
+A reference is a unique integer key.
+As long as you do not manually add integer keys into table <code>t</code>,
+<a href="#luaL_ref"><code>luaL_ref</code></a> ensures the uniqueness of the key it returns.
+You can retrieve an object referred by reference <code>r</code>
+by calling <code>lua_rawgeti(L, t, r)</code>.
+Function <a href="#luaL_unref"><code>luaL_unref</code></a> frees a reference and its associated object.
+
+
+<p>
+If the object at the top of the stack is <b>nil</b>,
+<a href="#luaL_ref"><code>luaL_ref</code></a> returns the constant <a name="pdf-LUA_REFNIL"><code>LUA_REFNIL</code></a>.
+The constant <a name="pdf-LUA_NOREF"><code>LUA_NOREF</code></a> is guaranteed to be different
+from any reference returned by <a href="#luaL_ref"><code>luaL_ref</code></a>.
+
+
+
+
+
+<hr><h3><a name="luaL_Reg"><code>luaL_Reg</code></a></h3>
+<pre>typedef struct luaL_Reg {
+  const char *name;
+  lua_CFunction func;
+} luaL_Reg;</pre>
+
+<p>
+Type for arrays of functions to be registered by
+<a href="#luaL_register"><code>luaL_register</code></a>.
+<code>name</code> is the function name and <code>func</code> is a pointer to
+the function.
+Any array of <a href="#luaL_Reg"><code>luaL_Reg</code></a> must end with an sentinel entry
+in which both <code>name</code> and <code>func</code> are <code>NULL</code>.
+
+
+
+
+
+<hr><h3><a name="luaL_register"><code>luaL_register</code></a></h3><p>
+<span class="apii">[-(0|1), +1, <em>m</em>]</span>
+<pre>void luaL_register (lua_State *L,
+                    const char *libname,
+                    const luaL_Reg *l);</pre>
+
+<p>
+Opens a library.
+
+
+<p>
+When called with <code>libname</code> equal to <code>NULL</code>,
+it simply registers all functions in the list <code>l</code>
+(see <a href="#luaL_Reg"><code>luaL_Reg</code></a>) into the table on the top of the stack.
+
+
+<p>
+When called with a non-null <code>libname</code>,
+<code>luaL_register</code> creates a new table <code>t</code>,
+sets it as the value of the global variable <code>libname</code>,
+sets it as the value of <code>package.loaded[libname]</code>,
+and registers on it all functions in the list <code>l</code>.
+If there is a table in <code>package.loaded[libname]</code> or in
+variable <code>libname</code>,
+reuses this table instead of creating a new one.
+
+
+<p>
+In any case the function leaves the table
+on the top of the stack.
+
+
+
+
+
+<hr><h3><a name="luaL_typename"><code>luaL_typename</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>const char *luaL_typename (lua_State *L, int index);</pre>
+
+<p>
+Returns the name of the type of the value at the given index.
+
+
+
+
+
+<hr><h3><a name="luaL_typerror"><code>luaL_typerror</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>int luaL_typerror (lua_State *L, int narg, const char *tname);</pre>
+
+<p>
+Generates an error with a message like the following:
+
+<pre>
+     <em>location</em>: bad argument <em>narg</em> to '<em>func</em>' (<em>tname</em> expected, got <em>rt</em>)
+</pre><p>
+where <code><em>location</em></code> is produced by <a href="#luaL_where"><code>luaL_where</code></a>,
+<code><em>func</em></code> is the name of the current function,
+and <code><em>rt</em></code> is the type name of the actual argument.
+
+
+
+
+
+<hr><h3><a name="luaL_unref"><code>luaL_unref</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>void luaL_unref (lua_State *L, int t, int ref);</pre>
+
+<p>
+Releases reference <code>ref</code> from the table at index <code>t</code>
+(see <a href="#luaL_ref"><code>luaL_ref</code></a>).
+The entry is removed from the table,
+so that the referred object can be collected.
+The reference <code>ref</code> is also freed to be used again.
+
+
+<p>
+If <code>ref</code> is <a href="#pdf-LUA_NOREF"><code>LUA_NOREF</code></a> or <a href="#pdf-LUA_REFNIL"><code>LUA_REFNIL</code></a>,
+<a href="#luaL_unref"><code>luaL_unref</code></a> does nothing.
+
+
+
+
+
+<hr><h3><a name="luaL_where"><code>luaL_where</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>void luaL_where (lua_State *L, int lvl);</pre>
+
+<p>
+Pushes onto the stack a string identifying the current position
+of the control at level <code>lvl</code> in the call stack.
+Typically this string has the following format:
+
+<pre>
+     <em>chunkname</em>:<em>currentline</em>:
+</pre><p>
+Level&nbsp;0 is the running function,
+level&nbsp;1 is the function that called the running function,
+etc.
+
+
+<p>
+This function is used to build a prefix for error messages.
+
+
+
+
+
+
+
+<h1>5 - <a name="5">Standard Libraries</a></h1>
+
+<p>
+The standard Lua libraries provide useful functions
+that are implemented directly through the C&nbsp;API.
+Some of these functions provide essential services to the language
+(e.g., <a href="#pdf-type"><code>type</code></a> and <a href="#pdf-getmetatable"><code>getmetatable</code></a>);
+others provide access to "outside" services (e.g., I/O);
+and others could be implemented in Lua itself,
+but are quite useful or have critical performance requirements that
+deserve an implementation in C (e.g., <a href="#pdf-table.sort"><code>table.sort</code></a>).
+
+
+<p>
+All libraries are implemented through the official C&nbsp;API
+and are provided as separate C&nbsp;modules.
+Currently, Lua has the following standard libraries:
+
+<ul>
+
+<li>basic library;</li>
+
+<li>package library;</li>
+
+<li>string manipulation;</li>
+
+<li>table manipulation;</li>
+
+<li>mathematical functions (sin, log, etc.);</li>
+
+<li>input and output;</li>
+
+<li>operating system facilities;</li>
+
+<li>debug facilities.</li>
+
+</ul><p>
+Except for the basic and package libraries,
+each library provides all its functions as fields of a global table
+or as methods of its objects.
+
+
+<p>
+To have access to these libraries,
+the C&nbsp;host program should call the <a href="#luaL_openlibs"><code>luaL_openlibs</code></a> function,
+which opens all standard libraries.
+Alternatively,
+it can open them individually by calling
+<a name="pdf-luaopen_base"><code>luaopen_base</code></a> (for the basic library),
+<a name="pdf-luaopen_package"><code>luaopen_package</code></a> (for the package library),
+<a name="pdf-luaopen_string"><code>luaopen_string</code></a> (for the string library),
+<a name="pdf-luaopen_table"><code>luaopen_table</code></a> (for the table library),
+<a name="pdf-luaopen_math"><code>luaopen_math</code></a> (for the mathematical library),
+<a name="pdf-luaopen_io"><code>luaopen_io</code></a> (for the I/O library),
+<a name="pdf-luaopen_os"><code>luaopen_os</code></a> (for the Operating System library),
+and <a name="pdf-luaopen_debug"><code>luaopen_debug</code></a> (for the debug library).
+These functions are declared in <a name="pdf-lualib.h"><code>lualib.h</code></a>
+and should not be called directly:
+you must call them like any other Lua C&nbsp;function,
+e.g., by using <a href="#lua_call"><code>lua_call</code></a>.
+
+
+
+<h2>5.1 - <a name="5.1">Basic Functions</a></h2>
+
+<p>
+The basic library provides some core functions to Lua.
+If you do not include this library in your application,
+you should check carefully whether you need to provide 
+implementations for some of its facilities.
+
+
+<p>
+<hr><h3><a name="pdf-assert"><code>assert (v [, message])</code></a></h3>
+Issues an  error when
+the value of its argument <code>v</code> is false (i.e., <b>nil</b> or <b>false</b>);
+otherwise, returns all its arguments.
+<code>message</code> is an error message;
+when absent, it defaults to "assertion failed!"
+
+
+
+
+<p>
+<hr><h3><a name="pdf-collectgarbage"><code>collectgarbage (opt [, arg])</code></a></h3>
+
+
+<p>
+This function is a generic interface to the garbage collector.
+It performs different functions according to its first argument, <code>opt</code>:
+
+<ul>
+
+<li><b>"stop":</b>
+stops the garbage collector.
+</li>
+
+<li><b>"restart":</b>
+restarts the garbage collector.
+</li>
+
+<li><b>"collect":</b>
+performs a full garbage-collection cycle.
+</li>
+
+<li><b>"count":</b>
+returns the total memory in use by Lua (in Kbytes).
+</li>
+
+<li><b>"step":</b>
+performs a garbage-collection step.
+The step "size" is controlled by <code>arg</code>
+(larger values mean more steps) in a non-specified way.
+If you want to control the step size
+you must experimentally tune the value of <code>arg</code>.
+Returns <b>true</b> if the step finished a collection cycle.
+</li>
+
+<li><b>"setpause":</b>
+sets <code>arg</code>/100 as the new value for the <em>pause</em> of
+the collector (see <a href="#2.10">&sect;2.10</a>).
+</li>
+
+<li><b>"setstepmul":</b>
+sets <code>arg</code>/100 as the new value for the <em>step multiplier</em> of
+the collector (see <a href="#2.10">&sect;2.10</a>).
+</li>
+
+</ul>
+
+
+
+<p>
+<hr><h3><a name="pdf-dofile"><code>dofile (filename)</code></a></h3>
+Opens the named file and executes its contents as a Lua chunk.
+When called without arguments,
+<code>dofile</code> executes the contents of the standard input (<code>stdin</code>).
+Returns all values returned by the chunk.
+In case of errors, <code>dofile</code> propagates the error
+to its caller (that is, <code>dofile</code> does not run in protected mode).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-error"><code>error (message [, level])</code></a></h3>
+Terminates the last protected function called
+and returns <code>message</code> as the error message.
+Function <code>error</code> never returns.
+
+
+<p>
+Usually, <code>error</code> adds some information about the error position
+at the beginning of the message.
+The <code>level</code> argument specifies how to get the error position.
+With level&nbsp;1 (the default), the error position is where the
+<code>error</code> function was called.
+Level&nbsp;2 points the error to where the function
+that called <code>error</code> was called; and so on.
+Passing a level&nbsp;0 avoids the addition of error position information
+to the message.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-_G"><code>_G</code></a></h3>
+A global variable (not a function) that
+holds the global environment (that is, <code>_G._G = _G</code>).
+Lua itself does not use this variable;
+changing its value does not affect any environment,
+nor vice-versa.
+(Use <a href="#pdf-setfenv"><code>setfenv</code></a> to change environments.)
+
+
+
+
+<p>
+<hr><h3><a name="pdf-getfenv"><code>getfenv ([f])</code></a></h3>
+Returns the current environment in use by the function.
+<code>f</code> can be a Lua function or a number
+that specifies the function at that stack level:
+Level&nbsp;1 is the function calling <code>getfenv</code>.
+If the given function is not a Lua function,
+or if <code>f</code> is 0,
+<code>getfenv</code> returns the global environment.
+The default for <code>f</code> is 1.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-getmetatable"><code>getmetatable (object)</code></a></h3>
+
+
+<p>
+If <code>object</code> does not have a metatable, returns <b>nil</b>.
+Otherwise,
+if the object's metatable has a <code>"__metatable"</code> field,
+returns the associated value.
+Otherwise, returns the metatable of the given object.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-ipairs"><code>ipairs (t)</code></a></h3>
+
+
+<p>
+Returns three values: an iterator function, the table <code>t</code>, and 0,
+so that the construction
+
+<pre>
+     for i,v in ipairs(t) do <em>body</em> end
+</pre><p>
+will iterate over the pairs (<code>1,t[1]</code>), (<code>2,t[2]</code>), &middot;&middot;&middot;,
+up to the first integer key absent from the table.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-load"><code>load (func [, chunkname])</code></a></h3>
+
+
+<p>
+Loads a chunk using function <code>func</code> to get its pieces.
+Each call to <code>func</code> must return a string that concatenates
+with previous results.
+A return of <b>nil</b> (or no value) signals the end of the chunk.
+
+
+<p>
+If there are no errors, 
+returns the compiled chunk as a function;
+otherwise, returns <b>nil</b> plus the error message.
+The environment of the returned function is the global environment.
+
+
+<p>
+<code>chunkname</code> is used as the chunk name for error messages
+and debug information.
+When absent,
+it defaults to "<code>=(load)</code>".
+
+
+
+
+<p>
+<hr><h3><a name="pdf-loadfile"><code>loadfile ([filename])</code></a></h3>
+
+
+<p>
+Similar to <a href="#pdf-load"><code>load</code></a>,
+but gets the chunk from file <code>filename</code>
+or from the standard input,
+if no file name is given.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-loadstring"><code>loadstring (string [, chunkname])</code></a></h3>
+
+
+<p>
+Similar to <a href="#pdf-load"><code>load</code></a>,
+but gets the chunk from the given string.
+
+
+<p>
+To load and run a given string, use the idiom
+
+<pre>
+     assert(loadstring(s))()
+</pre>
+
+<p>
+When absent,
+<code>chunkname</code> defaults to the given string.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-next"><code>next (table [, index])</code></a></h3>
+
+
+<p>
+Allows a program to traverse all fields of a table.
+Its first argument is a table and its second argument
+is an index in this table.
+<code>next</code> returns the next index of the table
+and its associated value.
+When called with <b>nil</b> as its second argument,
+<code>next</code> returns an initial index
+and its associated value.
+When called with the last index,
+or with <b>nil</b> in an empty table,
+<code>next</code> returns <b>nil</b>.
+If the second argument is absent, then it is interpreted as <b>nil</b>.
+In particular,
+you can use <code>next(t)</code> to check whether a table is empty.
+
+
+<p>
+The order in which the indices are enumerated is not specified,
+<em>even for numeric indices</em>.
+(To traverse a table in numeric order,
+use a numerical <b>for</b> or the <a href="#pdf-ipairs"><code>ipairs</code></a> function.)
+
+
+<p>
+The behavior of <code>next</code> is <em>undefined</em> if,
+during the traversal,
+you assign any value to a non-existent field in the table.
+You may however modify existing fields.
+In particular, you may clear existing fields.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-pairs"><code>pairs (t)</code></a></h3>
+
+
+<p>
+Returns three values: the <a href="#pdf-next"><code>next</code></a> function, the table <code>t</code>, and <b>nil</b>,
+so that the construction
+
+<pre>
+     for k,v in pairs(t) do <em>body</em> end
+</pre><p>
+will iterate over all key&ndash;value pairs of table <code>t</code>.
+
+
+<p>
+See function <a href="#pdf-next"><code>next</code></a> for the caveats of modifying
+the table during its traversal.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-pcall"><code>pcall (f, arg1, &middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Calls function <code>f</code> with
+the given arguments in <em>protected mode</em>.
+This means that any error inside&nbsp;<code>f</code> is not propagated;
+instead, <code>pcall</code> catches the error
+and returns a status code.
+Its first result is the status code (a boolean),
+which is true if the call succeeds without errors.
+In such case, <code>pcall</code> also returns all results from the call,
+after this first result.
+In case of any error, <code>pcall</code> returns <b>false</b> plus the error message.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-print"><code>print (&middot;&middot;&middot;)</code></a></h3>
+Receives any number of arguments,
+and prints their values to <code>stdout</code>,
+using the <a href="#pdf-tostring"><code>tostring</code></a> function to convert them to strings.
+<code>print</code> is not intended for formatted output,
+but only as a quick way to show a value,
+typically for debugging.
+For formatted output, use <a href="#pdf-string.format"><code>string.format</code></a>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-rawequal"><code>rawequal (v1, v2)</code></a></h3>
+Checks whether <code>v1</code> is equal to <code>v2</code>,
+without invoking any metamethod.
+Returns a boolean.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-rawget"><code>rawget (table, index)</code></a></h3>
+Gets the real value of <code>table[index]</code>,
+without invoking any metamethod.
+<code>table</code> must be a table;
+<code>index</code> may be any value.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-rawset"><code>rawset (table, index, value)</code></a></h3>
+Sets the real value of <code>table[index]</code> to <code>value</code>,
+without invoking any metamethod.
+<code>table</code> must be a table,
+<code>index</code> any value different from <b>nil</b>,
+and <code>value</code> any Lua value.
+
+
+<p>
+This function returns <code>table</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-select"><code>select (index, &middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+If <code>index</code> is a number,
+returns all arguments after argument number <code>index</code>.
+Otherwise, <code>index</code> must be the string <code>"#"</code>,
+and <code>select</code> returns the total number of extra arguments it received.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-setfenv"><code>setfenv (f, table)</code></a></h3>
+
+
+<p>
+Sets the environment to be used by the given function.
+<code>f</code> can be a Lua function or a number
+that specifies the function at that stack level:
+Level&nbsp;1 is the function calling <code>setfenv</code>.
+<code>setfenv</code> returns the given function.
+
+
+<p>
+As a special case, when <code>f</code> is 0 <code>setfenv</code> changes
+the environment of the running thread.
+In this case, <code>setfenv</code> returns no values.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-setmetatable"><code>setmetatable (table, metatable)</code></a></h3>
+
+
+<p>
+Sets the metatable for the given table.
+(You cannot change the metatable of other types from Lua, only from&nbsp;C.)
+If <code>metatable</code> is <b>nil</b>,
+removes the metatable of the given table.
+If the original metatable has a <code>"__metatable"</code> field,
+raises an error.
+
+
+<p>
+This function returns <code>table</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-tonumber"><code>tonumber (e [, base])</code></a></h3>
+Tries to convert its argument to a number.
+If the argument is already a number or a string convertible
+to a number, then <code>tonumber</code> returns this number;
+otherwise, it returns <b>nil</b>.
+
+
+<p>
+An optional argument specifies the base to interpret the numeral.
+The base may be any integer between 2 and 36, inclusive.
+In bases above&nbsp;10, the letter '<code>A</code>' (in either upper or lower case)
+represents&nbsp;10, '<code>B</code>' represents&nbsp;11, and so forth,
+with '<code>Z</code>' representing 35.
+In base 10 (the default), the number may have a decimal part,
+as well as an optional exponent part (see <a href="#2.1">&sect;2.1</a>).
+In other bases, only unsigned integers are accepted.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-tostring"><code>tostring (e)</code></a></h3>
+Receives an argument of any type and
+converts it to a string in a reasonable format.
+For complete control of how numbers are converted,
+use <a href="#pdf-string.format"><code>string.format</code></a>.
+
+
+<p>
+If the metatable of <code>e</code> has a <code>"__tostring"</code> field,
+then <code>tostring</code> calls the corresponding value
+with <code>e</code> as argument,
+and uses the result of the call as its result.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-type"><code>type (v)</code></a></h3>
+Returns the type of its only argument, coded as a string.
+The possible results of this function are
+"<code>nil</code>" (a string, not the value <b>nil</b>),
+"<code>number</code>",
+"<code>string</code>",
+"<code>boolean</code>",
+"<code>table</code>",
+"<code>function</code>",
+"<code>thread</code>",
+and "<code>userdata</code>".
+
+
+
+
+<p>
+<hr><h3><a name="pdf-unpack"><code>unpack (list [, i [, j]])</code></a></h3>
+Returns the elements from the given table.
+This function is equivalent to
+
+<pre>
+     return list[i], list[i+1], &middot;&middot;&middot;, list[j]
+</pre><p>
+except that the above code can be written only for a fixed number
+of elements.
+By default, <code>i</code> is&nbsp;1 and <code>j</code> is the length of the list,
+as defined by the length operator (see <a href="#2.5.5">&sect;2.5.5</a>).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-_VERSION"><code>_VERSION</code></a></h3>
+A global variable (not a function) that
+holds a string containing the current interpreter version.
+The current contents of this variable is "<code>Lua 5.1</code>".
+
+
+
+
+<p>
+<hr><h3><a name="pdf-xpcall"><code>xpcall (f, err)</code></a></h3>
+
+
+<p>
+This function is similar to <a href="#pdf-pcall"><code>pcall</code></a>,
+except that you can set a new error handler.
+
+
+<p>
+<code>xpcall</code> calls function <code>f</code> in protected mode,
+using <code>err</code> as the error handler.
+Any error inside <code>f</code> is not propagated;
+instead, <code>xpcall</code> catches the error,
+calls the <code>err</code> function with the original error object,
+and returns a status code.
+Its first result is the status code (a boolean),
+which is true if the call succeeds without errors.
+In this case, <code>xpcall</code> also returns all results from the call,
+after this first result.
+In case of any error,
+<code>xpcall</code> returns <b>false</b> plus the result from <code>err</code>.
+
+
+
+
+
+
+
+<h2>5.2 - <a name="5.2">Coroutine Manipulation</a></h2>
+
+<p>
+The operations related to coroutines comprise a sub-library of
+the basic library and come inside the table <a name="pdf-coroutine"><code>coroutine</code></a>.
+See <a href="#2.11">&sect;2.11</a> for a general description of coroutines.
+
+
+<p>
+<hr><h3><a name="pdf-coroutine.create"><code>coroutine.create (f)</code></a></h3>
+
+
+<p>
+Creates a new coroutine, with body <code>f</code>.
+<code>f</code> must be a Lua function.
+Returns this new coroutine,
+an object with type <code>"thread"</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-coroutine.resume"><code>coroutine.resume (co [, val1, &middot;&middot;&middot;])</code></a></h3>
+
+
+<p>
+Starts or continues the execution of coroutine <code>co</code>.
+The first time you resume a coroutine,
+it starts running its body.
+The values <code>val1</code>, &middot;&middot;&middot; are passed
+as the arguments to the body function.
+If the coroutine has yielded,
+<code>resume</code> restarts it;
+the values <code>val1</code>, &middot;&middot;&middot; are passed
+as the results from the yield.
+
+
+<p>
+If the coroutine runs without any errors,
+<code>resume</code> returns <b>true</b> plus any values passed to <code>yield</code>
+(if the coroutine yields) or any values returned by the body function
+(if the coroutine terminates).
+If there is any error,
+<code>resume</code> returns <b>false</b> plus the error message.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-coroutine.running"><code>coroutine.running ()</code></a></h3>
+
+
+<p>
+Returns the running coroutine,
+or <b>nil</b> when called by the main thread.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-coroutine.status"><code>coroutine.status (co)</code></a></h3>
+
+
+<p>
+Returns the status of coroutine <code>co</code>, as a string:
+<code>"running"</code>,
+if the coroutine is running (that is, it called <code>status</code>);
+<code>"suspended"</code>, if the coroutine is suspended in a call to <code>yield</code>,
+or if it has not started running yet;
+<code>"normal"</code> if the coroutine is active but not running
+(that is, it has resumed another coroutine);
+and <code>"dead"</code> if the coroutine has finished its body function,
+or if it has stopped with an error.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-coroutine.wrap"><code>coroutine.wrap (f)</code></a></h3>
+
+
+<p>
+Creates a new coroutine, with body <code>f</code>.
+<code>f</code> must be a Lua function.
+Returns a function that resumes the coroutine each time it is called.
+Any arguments passed to the function behave as the
+extra arguments to <code>resume</code>.
+Returns the same values returned by <code>resume</code>,
+except the first boolean.
+In case of error, propagates the error.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-coroutine.yield"><code>coroutine.yield (&middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Suspends the execution of the calling coroutine.
+The coroutine cannot be running a C&nbsp;function,
+a metamethod, or an iterator.
+Any arguments to <code>yield</code> are passed as extra results to <code>resume</code>.
+
+
+
+
+
+
+
+<h2>5.3 - <a name="5.3">Modules</a></h2>
+
+<p>
+The package library provides basic
+facilities for loading and building modules in Lua.
+It exports two of its functions directly in the global environment:
+<a href="#pdf-require"><code>require</code></a> and <a href="#pdf-module"><code>module</code></a>.
+Everything else is exported in a table <a name="pdf-package"><code>package</code></a>.
+
+
+<p>
+<hr><h3><a name="pdf-module"><code>module (name [, &middot;&middot;&middot;])</code></a></h3>
+
+
+<p>
+Creates a module.
+If there is a table in <code>package.loaded[name]</code>,
+this table is the module.
+Otherwise, if there is a global table <code>t</code> with the given name,
+this table is the module.
+Otherwise creates a new table <code>t</code> and
+sets it as the value of the global <code>name</code> and
+the value of <code>package.loaded[name]</code>.
+This function also initializes <code>t._NAME</code> with the given name,
+<code>t._M</code> with the module (<code>t</code> itself),
+and <code>t._PACKAGE</code> with the package name
+(the full module name minus last component; see below).
+Finally, <code>module</code> sets <code>t</code> as the new environment
+of the current function and the new value of <code>package.loaded[name]</code>,
+so that <a href="#pdf-require"><code>require</code></a> returns <code>t</code>.
+
+
+<p>
+If <code>name</code> is a compound name
+(that is, one with components separated by dots),
+<code>module</code> creates (or reuses, if they already exist)
+tables for each component.
+For instance, if <code>name</code> is <code>a.b.c</code>,
+then <code>module</code> stores the module table in field <code>c</code> of
+field <code>b</code> of global <code>a</code>.
+
+
+<p>
+This function may receive optional <em>options</em> after
+the module name,
+where each option is a function to be applied over the module.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-require"><code>require (modname)</code></a></h3>
+
+
+<p>
+Loads the given module.
+The function starts by looking into the <a href="#pdf-package.loaded"><code>package.loaded</code></a> table
+to determine whether <code>modname</code> is already loaded.
+If it is, then <code>require</code> returns the value stored
+at <code>package.loaded[modname]</code>.
+Otherwise, it tries to find a <em>loader</em> for the module.
+
+
+<p>
+To find a loader,
+<code>require</code> is guided by the <a href="#pdf-package.loaders"><code>package.loaders</code></a> array.
+By changing this array,
+we can change how <code>require</code> looks for a module.
+The following explanation is based on the default configuration
+for <a href="#pdf-package.loaders"><code>package.loaders</code></a>.
+
+
+<p>
+First <code>require</code> queries <code>package.preload[modname]</code>.
+If it has a value,
+this value (which should be a function) is the loader.
+Otherwise <code>require</code> searches for a Lua loader using the
+path stored in <a href="#pdf-package.path"><code>package.path</code></a>.
+If that also fails, it searches for a C&nbsp;loader using the
+path stored in <a href="#pdf-package.cpath"><code>package.cpath</code></a>.
+If that also fails,
+it tries an <em>all-in-one</em> loader (see <a href="#pdf-package.loaders"><code>package.loaders</code></a>).
+
+
+<p>
+Once a loader is found,
+<code>require</code> calls the loader with a single argument, <code>modname</code>.
+If the loader returns any value,
+<code>require</code> assigns the returned value to <code>package.loaded[modname]</code>.
+If the loader returns no value and
+has not assigned any value to <code>package.loaded[modname]</code>,
+then <code>require</code> assigns <b>true</b> to this entry.
+In any case, <code>require</code> returns the
+final value of <code>package.loaded[modname]</code>.
+
+
+<p>
+If there is any error loading or running the module,
+or if it cannot find any loader for the module,
+then <code>require</code> signals an error. 
+
+
+
+
+<p>
+<hr><h3><a name="pdf-package.cpath"><code>package.cpath</code></a></h3>
+
+
+<p>
+The path used by <a href="#pdf-require"><code>require</code></a> to search for a C&nbsp;loader.
+
+
+<p>
+Lua initializes the C&nbsp;path <a href="#pdf-package.cpath"><code>package.cpath</code></a> in the same way
+it initializes the Lua path <a href="#pdf-package.path"><code>package.path</code></a>,
+using the environment variable <a name="pdf-LUA_CPATH"><code>LUA_CPATH</code></a>
+or a default path defined in <code>luaconf.h</code>.
+
+
+
+
+<p>
+
+<hr><h3><a name="pdf-package.loaded"><code>package.loaded</code></a></h3>
+
+
+<p>
+A table used by <a href="#pdf-require"><code>require</code></a> to control which
+modules are already loaded.
+When you require a module <code>modname</code> and
+<code>package.loaded[modname]</code> is not false,
+<a href="#pdf-require"><code>require</code></a> simply returns the value stored there.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-package.loaders"><code>package.loaders</code></a></h3>
+
+
+<p>
+A table used by <a href="#pdf-require"><code>require</code></a> to control how to load modules.
+
+
+<p>
+Each entry in this table is a <em>searcher function</em>.
+When looking for a module,
+<a href="#pdf-require"><code>require</code></a> calls each of these searchers in ascending order,
+with the module name (the argument given to <a href="#pdf-require"><code>require</code></a>) as its
+sole parameter.
+The function may return another function (the module <em>loader</em>)
+or a string explaining why it did not find that module
+(or <b>nil</b> if it has nothing to say).
+Lua initializes this table with four functions.
+
+
+<p>
+The first searcher simply looks for a loader in the
+<a href="#pdf-package.preload"><code>package.preload</code></a> table.
+
+
+<p>
+The second searcher looks for a loader as a Lua library,
+using the path stored at <a href="#pdf-package.path"><code>package.path</code></a>.
+A path is a sequence of <em>templates</em> separated by semicolons.
+For each template,
+the searcher will change each interrogation
+mark in the template by <code>filename</code>,
+which is the module name with each dot replaced by a
+"directory separator" (such as "<code>/</code>" in Unix);
+then it will try to open the resulting file name.
+So, for instance, if the Lua path is the string
+
+<pre>
+     "./?.lua;./?.lc;/usr/local/?/init.lua"
+</pre><p>
+the search for a Lua file for module <code>foo</code>
+will try to open the files
+<code>./foo.lua</code>, <code>./foo.lc</code>, and
+<code>/usr/local/foo/init.lua</code>, in that order.
+
+
+<p>
+The third searcher looks for a loader as a C&nbsp;library,
+using the path given by the variable <a href="#pdf-package.cpath"><code>package.cpath</code></a>.
+For instance,
+if the C&nbsp;path is the string
+
+<pre>
+     "./?.so;./?.dll;/usr/local/?/init.so"
+</pre><p>
+the searcher for module <code>foo</code>
+will try to open the files <code>./foo.so</code>, <code>./foo.dll</code>,
+and <code>/usr/local/foo/init.so</code>, in that order.
+Once it finds a C&nbsp;library,
+this searcher first uses a dynamic link facility to link the
+application with the library.
+Then it tries to find a C&nbsp;function inside the library to
+be used as the loader.
+The name of this C&nbsp;function is the string "<code>luaopen_</code>"
+concatenated with a copy of the module name where each dot
+is replaced by an underscore.
+Moreover, if the module name has a hyphen,
+its prefix up to (and including) the first hyphen is removed.
+For instance, if the module name is <code>a.v1-b.c</code>,
+the function name will be <code>luaopen_b_c</code>.
+
+
+<p>
+The fourth searcher tries an <em>all-in-one loader</em>.
+It searches the C&nbsp;path for a library for
+the root name of the given module.
+For instance, when requiring <code>a.b.c</code>,
+it will search for a C&nbsp;library for <code>a</code>.
+If found, it looks into it for an open function for
+the submodule;
+in our example, that would be <code>luaopen_a_b_c</code>.
+With this facility, a package can pack several C&nbsp;submodules
+into one single library,
+with each submodule keeping its original open function.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-package.loadlib"><code>package.loadlib (libname, funcname)</code></a></h3>
+
+
+<p>
+Dynamically links the host program with the C&nbsp;library <code>libname</code>.
+Inside this library, looks for a function <code>funcname</code>
+and returns this function as a C&nbsp;function.
+(So, <code>funcname</code> must follow the protocol (see <a href="#lua_CFunction"><code>lua_CFunction</code></a>)).
+
+
+<p>
+This is a low-level function.
+It completely bypasses the package and module system.
+Unlike <a href="#pdf-require"><code>require</code></a>,
+it does not perform any path searching and
+does not automatically adds extensions.
+<code>libname</code> must be the complete file name of the C&nbsp;library,
+including if necessary a path and extension.
+<code>funcname</code> must be the exact name exported by the C&nbsp;library
+(which may depend on the C&nbsp;compiler and linker used).
+
+
+<p>
+This function is not supported by ANSI C.
+As such, it is only available on some platforms
+(Windows, Linux, Mac OS X, Solaris, BSD,
+plus other Unix systems that support the <code>dlfcn</code> standard).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-package.path"><code>package.path</code></a></h3>
+
+
+<p>
+The path used by <a href="#pdf-require"><code>require</code></a> to search for a Lua loader.
+
+
+<p>
+At start-up, Lua initializes this variable with
+the value of the environment variable <a name="pdf-LUA_PATH"><code>LUA_PATH</code></a> or
+with a default path defined in <code>luaconf.h</code>,
+if the environment variable is not defined.
+Any "<code>;;</code>" in the value of the environment variable
+is replaced by the default path.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-package.preload"><code>package.preload</code></a></h3>
+
+
+<p>
+A table to store loaders for specific modules
+(see <a href="#pdf-require"><code>require</code></a>).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-package.seeall"><code>package.seeall (module)</code></a></h3>
+
+
+<p>
+Sets a metatable for <code>module</code> with
+its <code>__index</code> field referring to the global environment,
+so that this module inherits values
+from the global environment.
+To be used as an option to function <a href="#pdf-module"><code>module</code></a>.
+
+
+
+
+
+
+
+<h2>5.4 - <a name="5.4">String Manipulation</a></h2>
+
+<p>
+This library provides generic functions for string manipulation,
+such as finding and extracting substrings, and pattern matching.
+When indexing a string in Lua, the first character is at position&nbsp;1
+(not at&nbsp;0, as in C).
+Indices are allowed to be negative and are interpreted as indexing backwards,
+from the end of the string.
+Thus, the last character is at position -1, and so on.
+
+
+<p>
+The string library provides all its functions inside the table
+<a name="pdf-string"><code>string</code></a>.
+It also sets a metatable for strings
+where the <code>__index</code> field points to the <code>string</code> table.
+Therefore, you can use the string functions in object-oriented style.
+For instance, <code>string.byte(s, i)</code>
+can be written as <code>s:byte(i)</code>.
+
+
+<p>
+<hr><h3><a name="pdf-string.byte"><code>string.byte (s [, i [, j]])</code></a></h3>
+Returns the internal numerical codes of the characters <code>s[i]</code>,
+<code>s[i+1]</code>, &middot;&middot;&middot;, <code>s[j]</code>.
+The default value for <code>i</code> is&nbsp;1;
+the default value for <code>j</code> is&nbsp;<code>i</code>.
+
+
+<p>
+Note that numerical codes are not necessarily portable across platforms.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.char"><code>string.char (&middot;&middot;&middot;)</code></a></h3>
+Receives zero or more integers.
+Returns a string with length equal to the number of arguments,
+in which each character has the internal numerical code equal
+to its corresponding argument.
+
+
+<p>
+Note that numerical codes are not necessarily portable across platforms.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.dump"><code>string.dump (function)</code></a></h3>
+
+
+<p>
+Returns a string containing a binary representation of the given function,
+so that a later <a href="#pdf-loadstring"><code>loadstring</code></a> on this string returns
+a copy of the function.
+<code>function</code> must be a Lua function without upvalues.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.find"><code>string.find (s, pattern [, init [, plain]])</code></a></h3>
+Looks for the first match of
+<code>pattern</code> in the string <code>s</code>.
+If it finds a match, then <code>find</code> returns the indices of&nbsp;<code>s</code>
+where this occurrence starts and ends;
+otherwise, it returns <b>nil</b>.
+A third, optional numerical argument <code>init</code> specifies
+where to start the search;
+its default value is&nbsp;1 and may be negative.
+A value of <b>true</b> as a fourth, optional argument <code>plain</code>
+turns off the pattern matching facilities,
+so the function does a plain "find substring" operation,
+with no characters in <code>pattern</code> being considered "magic".
+Note that if <code>plain</code> is given, then <code>init</code> must be given as well.
+
+
+<p>
+If the pattern has captures,
+then in a successful match
+the captured values are also returned,
+after the two indices.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.format"><code>string.format (formatstring, &middot;&middot;&middot;)</code></a></h3>
+Returns a formatted version of its variable number of arguments
+following the description given in its first argument (which must be a string).
+The format string follows the same rules as the <code>printf</code> family of
+standard C&nbsp;functions.
+The only differences are that the options/modifiers
+<code>*</code>, <code>l</code>, <code>L</code>, <code>n</code>, <code>p</code>,
+and <code>h</code> are not supported
+and that there is an extra option, <code>q</code>.
+The <code>q</code> option formats a string in a form suitable to be safely read
+back by the Lua interpreter:
+the string is written between double quotes,
+and all double quotes, newlines, embedded zeros,
+and backslashes in the string
+are correctly escaped when written.
+For instance, the call
+
+<pre>
+     string.format('%q', 'a string with "quotes" and \n new line')
+</pre><p>
+will produce the string:
+
+<pre>
+     "a string with \"quotes\" and \
+      new line"
+</pre>
+
+<p>
+The options <code>c</code>, <code>d</code>, <code>E</code>, <code>e</code>, <code>f</code>,
+<code>g</code>, <code>G</code>, <code>i</code>, <code>o</code>, <code>u</code>, <code>X</code>, and <code>x</code> all
+expect a number as argument,
+whereas <code>q</code> and <code>s</code> expect a string.
+
+
+<p>
+This function does not accept string values
+containing embedded zeros,
+except as arguments to the <code>q</code> option.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.gmatch"><code>string.gmatch (s, pattern)</code></a></h3>
+Returns an iterator function that,
+each time it is called,
+returns the next captures from <code>pattern</code> over string <code>s</code>.
+If <code>pattern</code> specifies no captures,
+then the whole match is produced in each call.
+
+
+<p>
+As an example, the following loop
+
+<pre>
+     s = "hello world from Lua"
+     for w in string.gmatch(s, "%a+") do
+       print(w)
+     end
+</pre><p>
+will iterate over all the words from string <code>s</code>,
+printing one per line.
+The next example collects all pairs <code>key=value</code> from the
+given string into a table:
+
+<pre>
+     t = {}
+     s = "from=world, to=Lua"
+     for k, v in string.gmatch(s, "(%w+)=(%w+)") do
+       t[k] = v
+     end
+</pre>
+
+<p>
+For this function, a '<code>^</code>' at the start of a pattern does not
+work as an anchor, as this would prevent the iteration.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.gsub"><code>string.gsub (s, pattern, repl [, n])</code></a></h3>
+Returns a copy of <code>s</code>
+in which all (or the first <code>n</code>, if given)
+occurrences of the <code>pattern</code> have been
+replaced by a replacement string specified by <code>repl</code>,
+which may be a string, a table, or a function.
+<code>gsub</code> also returns, as its second value,
+the total number of matches that occurred.
+
+
+<p>
+If <code>repl</code> is a string, then its value is used for replacement.
+The character&nbsp;<code>%</code> works as an escape character:
+any sequence in <code>repl</code> of the form <code>%<em>n</em></code>,
+with <em>n</em> between 1 and 9,
+stands for the value of the <em>n</em>-th captured substring (see below).
+The sequence <code>%0</code> stands for the whole match.
+The sequence <code>%%</code> stands for a single&nbsp;<code>%</code>.
+
+
+<p>
+If <code>repl</code> is a table, then the table is queried for every match,
+using the first capture as the key;
+if the pattern specifies no captures,
+then the whole match is used as the key.
+
+
+<p>
+If <code>repl</code> is a function, then this function is called every time a
+match occurs, with all captured substrings passed as arguments,
+in order;
+if the pattern specifies no captures,
+then the whole match is passed as a sole argument.
+
+
+<p>
+If the value returned by the table query or by the function call
+is a string or a number,
+then it is used as the replacement string;
+otherwise, if it is <b>false</b> or <b>nil</b>,
+then there is no replacement
+(that is, the original match is kept in the string).
+
+
+<p>
+Here are some examples:
+
+<pre>
+     x = string.gsub("hello world", "(%w+)", "%1 %1")
+     --&gt; x="hello hello world world"
+     
+     x = string.gsub("hello world", "%w+", "%0 %0", 1)
+     --&gt; x="hello hello world"
+     
+     x = string.gsub("hello world from Lua", "(%w+)%s*(%w+)", "%2 %1")
+     --&gt; x="world hello Lua from"
+     
+     x = string.gsub("home = $HOME, user = $USER", "%$(%w+)", os.getenv)
+     --&gt; x="home = /home/roberto, user = roberto"
+     
+     x = string.gsub("4+5 = $return 4+5$", "%$(.-)%$", function (s)
+           return loadstring(s)()
+         end)
+     --&gt; x="4+5 = 9"
+     
+     local t = {name="lua", version="5.1"}
+     x = string.gsub("$name-$version.tar.gz", "%$(%w+)", t)
+     --&gt; x="lua-5.1.tar.gz"
+</pre>
+
+
+
+<p>
+<hr><h3><a name="pdf-string.len"><code>string.len (s)</code></a></h3>
+Receives a string and returns its length.
+The empty string <code>""</code> has length 0.
+Embedded zeros are counted,
+so <code>"a\000bc\000"</code> has length 5.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.lower"><code>string.lower (s)</code></a></h3>
+Receives a string and returns a copy of this string with all
+uppercase letters changed to lowercase.
+All other characters are left unchanged.
+The definition of what an uppercase letter is depends on the current locale.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.match"><code>string.match (s, pattern [, init])</code></a></h3>
+Looks for the first <em>match</em> of
+<code>pattern</code> in the string <code>s</code>.
+If it finds one, then <code>match</code> returns
+the captures from the pattern;
+otherwise it returns <b>nil</b>.
+If <code>pattern</code> specifies no captures,
+then the whole match is returned.
+A third, optional numerical argument <code>init</code> specifies
+where to start the search;
+its default value is&nbsp;1 and may be negative.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.rep"><code>string.rep (s, n)</code></a></h3>
+Returns a string that is the concatenation of <code>n</code> copies of
+the string <code>s</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.reverse"><code>string.reverse (s)</code></a></h3>
+Returns a string that is the string <code>s</code> reversed.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.sub"><code>string.sub (s, i [, j])</code></a></h3>
+Returns the substring of <code>s</code> that
+starts at <code>i</code>  and continues until <code>j</code>;
+<code>i</code> and <code>j</code> may be negative.
+If <code>j</code> is absent, then it is assumed to be equal to -1
+(which is the same as the string length).
+In particular,
+the call <code>string.sub(s,1,j)</code> returns a prefix of <code>s</code>
+with length <code>j</code>,
+and <code>string.sub(s, -i)</code> returns a suffix of <code>s</code>
+with length <code>i</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-string.upper"><code>string.upper (s)</code></a></h3>
+Receives a string and returns a copy of this string with all
+lowercase letters changed to uppercase.
+All other characters are left unchanged.
+The definition of what a lowercase letter is depends on the current locale.
+
+
+
+<h3>5.4.1 - <a name="5.4.1">Patterns</a></h3>
+
+
+<h4>Character Class:</h4><p>
+A <em>character class</em> is used to represent a set of characters.
+The following combinations are allowed in describing a character class:
+
+<ul>
+
+<li><b><em>x</em>:</b>
+(where <em>x</em> is not one of the <em>magic characters</em>
+<code>^$()%.[]*+-?</code>)
+represents the character <em>x</em> itself.
+</li>
+
+<li><b><code>.</code>:</b> (a dot) represents all characters.</li>
+
+<li><b><code>%a</code>:</b> represents all letters.</li>
+
+<li><b><code>%c</code>:</b> represents all control characters.</li>
+
+<li><b><code>%d</code>:</b> represents all digits.</li>
+
+<li><b><code>%l</code>:</b> represents all lowercase letters.</li>
+
+<li><b><code>%p</code>:</b> represents all punctuation characters.</li>
+
+<li><b><code>%s</code>:</b> represents all space characters.</li>
+
+<li><b><code>%u</code>:</b> represents all uppercase letters.</li>
+
+<li><b><code>%w</code>:</b> represents all alphanumeric characters.</li>
+
+<li><b><code>%x</code>:</b> represents all hexadecimal digits.</li>
+
+<li><b><code>%z</code>:</b> represents the character with representation 0.</li>
+
+<li><b><code>%<em>x</em></code>:</b> (where <em>x</em> is any non-alphanumeric character)
+represents the character <em>x</em>.
+This is the standard way to escape the magic characters.
+Any punctuation character (even the non magic)
+can be preceded by a '<code>%</code>'
+when used to represent itself in a pattern.
+</li>
+
+<li><b><code>[<em>set</em>]</code>:</b>
+represents the class which is the union of all
+characters in <em>set</em>.
+A range of characters may be specified by
+separating the end characters of the range with a '<code>-</code>'.
+All classes <code>%</code><em>x</em> described above may also be used as
+components in <em>set</em>.
+All other characters in <em>set</em> represent themselves.
+For example, <code>[%w_]</code> (or <code>[_%w]</code>)
+represents all alphanumeric characters plus the underscore,
+<code>[0-7]</code> represents the octal digits,
+and <code>[0-7%l%-]</code> represents the octal digits plus
+the lowercase letters plus the '<code>-</code>' character.
+
+
+<p>
+The interaction between ranges and classes is not defined.
+Therefore, patterns like <code>[%a-z]</code> or <code>[a-%%]</code>
+have no meaning.
+</li>
+
+<li><b><code>[^<em>set</em>]</code>:</b>
+represents the complement of <em>set</em>,
+where <em>set</em> is interpreted as above.
+</li>
+
+</ul><p>
+For all classes represented by single letters (<code>%a</code>, <code>%c</code>, etc.),
+the corresponding uppercase letter represents the complement of the class.
+For instance, <code>%S</code> represents all non-space characters.
+
+
+<p>
+The definitions of letter, space, and other character groups
+depend on the current locale.
+In particular, the class <code>[a-z]</code> may not be equivalent to <code>%l</code>.
+
+
+
+
+
+<h4>Pattern Item:</h4><p>
+A <em>pattern item</em> may be
+
+<ul>
+
+<li>
+a single character class,
+which matches any single character in the class;
+</li>
+
+<li>
+a single character class followed by '<code>*</code>',
+which matches 0 or more repetitions of characters in the class.
+These repetition items will always match the longest possible sequence;
+</li>
+
+<li>
+a single character class followed by '<code>+</code>',
+which matches 1 or more repetitions of characters in the class.
+These repetition items will always match the longest possible sequence;
+</li>
+
+<li>
+a single character class followed by '<code>-</code>',
+which also matches 0 or more repetitions of characters in the class.
+Unlike '<code>*</code>',
+these repetition items will always match the <em>shortest</em> possible sequence;
+</li>
+
+<li>
+a single character class followed by '<code>?</code>',
+which matches 0 or 1 occurrence of a character in the class;
+</li>
+
+<li>
+<code>%<em>n</em></code>, for <em>n</em> between 1 and 9;
+such item matches a substring equal to the <em>n</em>-th captured string
+(see below);
+</li>
+
+<li>
+<code>%b<em>xy</em></code>, where <em>x</em> and <em>y</em> are two distinct characters;
+such item matches strings that start with&nbsp;<em>x</em>, end with&nbsp;<em>y</em>,
+and where the <em>x</em> and <em>y</em> are <em>balanced</em>.
+This means that, if one reads the string from left to right,
+counting <em>+1</em> for an <em>x</em> and <em>-1</em> for a <em>y</em>,
+the ending <em>y</em> is the first <em>y</em> where the count reaches 0.
+For instance, the item <code>%b()</code> matches expressions with
+balanced parentheses.
+</li>
+
+</ul>
+
+
+
+
+<h4>Pattern:</h4><p>
+A <em>pattern</em> is a sequence of pattern items.
+A '<code>^</code>' at the beginning of a pattern anchors the match at the
+beginning of the subject string.
+A '<code>$</code>' at the end of a pattern anchors the match at the
+end of the subject string.
+At other positions,
+'<code>^</code>' and '<code>$</code>' have no special meaning and represent themselves.
+
+
+
+
+
+<h4>Captures:</h4><p>
+A pattern may contain sub-patterns enclosed in parentheses;
+they describe <em>captures</em>.
+When a match succeeds, the substrings of the subject string
+that match captures are stored (<em>captured</em>) for future use.
+Captures are numbered according to their left parentheses.
+For instance, in the pattern <code>"(a*(.)%w(%s*))"</code>,
+the part of the string matching <code>"a*(.)%w(%s*)"</code> is
+stored as the first capture (and therefore has number&nbsp;1);
+the character matching "<code>.</code>" is captured with number&nbsp;2,
+and the part matching "<code>%s*</code>" has number&nbsp;3.
+
+
+<p>
+As a special case, the empty capture <code>()</code> captures
+the current string position (a number).
+For instance, if we apply the pattern <code>"()aa()"</code> on the
+string <code>"flaaap"</code>, there will be two captures: 3&nbsp;and&nbsp;5.
+
+
+<p>
+A pattern cannot contain embedded zeros.  Use <code>%z</code> instead.
+
+
+
+
+
+
+
+
+
+
+
+<h2>5.5 - <a name="5.5">Table Manipulation</a></h2><p>
+This library provides generic functions for table manipulation.
+It provides all its functions inside the table <a name="pdf-table"><code>table</code></a>.
+
+
+<p>
+Most functions in the table library assume that the table
+represents an array or a list.
+For these functions, when we talk about the "length" of a table
+we mean the result of the length operator.
+
+
+<p>
+<hr><h3><a name="pdf-table.concat"><code>table.concat (table [, sep [, i [, j]]])</code></a></h3>
+Given an array where all elements are strings or numbers,
+returns <code>table[i]..sep..table[i+1] &middot;&middot;&middot; sep..table[j]</code>.
+The default value for <code>sep</code> is the empty string,
+the default for <code>i</code> is 1,
+and the default for <code>j</code> is the length of the table.
+If <code>i</code> is greater than <code>j</code>, returns the empty string.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-table.insert"><code>table.insert (table, [pos,] value)</code></a></h3>
+
+
+<p>
+Inserts element <code>value</code> at position <code>pos</code> in <code>table</code>,
+shifting up other elements to open space, if necessary.
+The default value for <code>pos</code> is <code>n+1</code>,
+where <code>n</code> is the length of the table (see <a href="#2.5.5">&sect;2.5.5</a>),
+so that a call <code>table.insert(t,x)</code> inserts <code>x</code> at the end
+of table <code>t</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-table.maxn"><code>table.maxn (table)</code></a></h3>
+
+
+<p>
+Returns the largest positive numerical index of the given table,
+or zero if the table has no positive numerical indices.
+(To do its job this function does a linear traversal of
+the whole table.) 
+
+
+
+
+<p>
+<hr><h3><a name="pdf-table.remove"><code>table.remove (table [, pos])</code></a></h3>
+
+
+<p>
+Removes from <code>table</code> the element at position <code>pos</code>,
+shifting down other elements to close the space, if necessary.
+Returns the value of the removed element.
+The default value for <code>pos</code> is <code>n</code>,
+where <code>n</code> is the length of the table,
+so that a call <code>table.remove(t)</code> removes the last element
+of table <code>t</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-table.sort"><code>table.sort (table [, comp])</code></a></h3>
+Sorts table elements in a given order, <em>in-place</em>,
+from <code>table[1]</code> to <code>table[n]</code>,
+where <code>n</code> is the length of the table.
+If <code>comp</code> is given,
+then it must be a function that receives two table elements,
+and returns true
+when the first is less than the second
+(so that <code>not comp(a[i+1],a[i])</code> will be true after the sort).
+If <code>comp</code> is not given,
+then the standard Lua operator <code>&lt;</code> is used instead.
+
+
+<p>
+The sort algorithm is not stable;
+that is, elements considered equal by the given order
+may have their relative positions changed by the sort.
+
+
+
+
+
+
+
+<h2>5.6 - <a name="5.6">Mathematical Functions</a></h2>
+
+<p>
+This library is an interface to the standard C&nbsp;math library.
+It provides all its functions inside the table <a name="pdf-math"><code>math</code></a>.
+
+
+<p>
+<hr><h3><a name="pdf-math.abs"><code>math.abs (x)</code></a></h3>
+
+
+<p>
+Returns the absolute value of <code>x</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.acos"><code>math.acos (x)</code></a></h3>
+
+
+<p>
+Returns the arc cosine of <code>x</code> (in radians).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.asin"><code>math.asin (x)</code></a></h3>
+
+
+<p>
+Returns the arc sine of <code>x</code> (in radians).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.atan"><code>math.atan (x)</code></a></h3>
+
+
+<p>
+Returns the arc tangent of <code>x</code> (in radians).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.atan2"><code>math.atan2 (y, x)</code></a></h3>
+
+
+<p>
+Returns the arc tangent of <code>y/x</code> (in radians),
+but uses the signs of both parameters to find the
+quadrant of the result.
+(It also handles correctly the case of <code>x</code> being zero.)
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.ceil"><code>math.ceil (x)</code></a></h3>
+
+
+<p>
+Returns the smallest integer larger than or equal to <code>x</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.cos"><code>math.cos (x)</code></a></h3>
+
+
+<p>
+Returns the cosine of <code>x</code> (assumed to be in radians).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.cosh"><code>math.cosh (x)</code></a></h3>
+
+
+<p>
+Returns the hyperbolic cosine of <code>x</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.deg"><code>math.deg (x)</code></a></h3>
+
+
+<p>
+Returns the angle <code>x</code> (given in radians) in degrees.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.exp"><code>math.exp (x)</code></a></h3>
+
+
+<p>
+Returns the value <em>e<sup>x</sup></em>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.floor"><code>math.floor (x)</code></a></h3>
+
+
+<p>
+Returns the largest integer smaller than or equal to <code>x</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.fmod"><code>math.fmod (x, y)</code></a></h3>
+
+
+<p>
+Returns the remainder of the division of <code>x</code> by <code>y</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.frexp"><code>math.frexp (x)</code></a></h3>
+
+
+<p>
+Returns <code>m</code> and <code>e</code> such that <em>x = m2<sup>e</sup></em>,
+<code>e</code> is an integer and the absolute value of <code>m</code> is
+in the range <em>[0.5, 1)</em>
+(or zero when <code>x</code> is zero).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.huge"><code>math.huge</code></a></h3>
+
+
+<p>
+The value <code>HUGE_VAL</code>,
+a value larger than or equal to any other numerical value.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.ldexp"><code>math.ldexp (m, e)</code></a></h3>
+
+
+<p>
+Returns <em>m2<sup>e</sup></em> (<code>e</code> should be an integer).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.log"><code>math.log (x)</code></a></h3>
+
+
+<p>
+Returns the natural logarithm of <code>x</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.log10"><code>math.log10 (x)</code></a></h3>
+
+
+<p>
+Returns the base-10 logarithm of <code>x</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.max"><code>math.max (x, &middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Returns the maximum value among its arguments.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.min"><code>math.min (x, &middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Returns the minimum value among its arguments.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.modf"><code>math.modf (x)</code></a></h3>
+
+
+<p>
+Returns two numbers,
+the integral part of <code>x</code> and the fractional part of <code>x</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.pi"><code>math.pi</code></a></h3>
+
+
+<p>
+The value of <em>pi</em>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.pow"><code>math.pow (x, y)</code></a></h3>
+
+
+<p>
+Returns <em>x<sup>y</sup></em>.
+(You can also use the expression <code>x^y</code> to compute this value.)
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.rad"><code>math.rad (x)</code></a></h3>
+
+
+<p>
+Returns the angle <code>x</code> (given in degrees) in radians.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.random"><code>math.random ([m [, n]])</code></a></h3>
+
+
+<p>
+This function is an interface to the simple
+pseudo-random generator function <code>rand</code> provided by ANSI&nbsp;C.
+(No guarantees can be given for its statistical properties.)
+
+
+<p>
+When called without arguments,
+returns a uniform pseudo-random real number
+in the range <em>[0,1)</em>.  
+When called with an integer number <code>m</code>,
+<code>math.random</code> returns
+a uniform pseudo-random integer in the range <em>[1, m]</em>.
+When called with two integer numbers <code>m</code> and <code>n</code>,
+<code>math.random</code> returns a uniform pseudo-random
+integer in the range <em>[m, n]</em>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.randomseed"><code>math.randomseed (x)</code></a></h3>
+
+
+<p>
+Sets <code>x</code> as the "seed"
+for the pseudo-random generator:
+equal seeds produce equal sequences of numbers.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.sin"><code>math.sin (x)</code></a></h3>
+
+
+<p>
+Returns the sine of <code>x</code> (assumed to be in radians).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.sinh"><code>math.sinh (x)</code></a></h3>
+
+
+<p>
+Returns the hyperbolic sine of <code>x</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.sqrt"><code>math.sqrt (x)</code></a></h3>
+
+
+<p>
+Returns the square root of <code>x</code>.
+(You can also use the expression <code>x^0.5</code> to compute this value.)
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.tan"><code>math.tan (x)</code></a></h3>
+
+
+<p>
+Returns the tangent of <code>x</code> (assumed to be in radians).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.tanh"><code>math.tanh (x)</code></a></h3>
+
+
+<p>
+Returns the hyperbolic tangent of <code>x</code>.
+
+
+
+
+
+
+
+<h2>5.7 - <a name="5.7">Input and Output Facilities</a></h2>
+
+<p>
+The I/O library provides two different styles for file manipulation.
+The first one uses implicit file descriptors;
+that is, there are operations to set a default input file and a
+default output file,
+and all input/output operations are over these default files.
+The second style uses explicit file descriptors.
+
+
+<p>
+When using implicit file descriptors,
+all operations are supplied by table <a name="pdf-io"><code>io</code></a>.
+When using explicit file descriptors,
+the operation <a href="#pdf-io.open"><code>io.open</code></a> returns a file descriptor
+and then all operations are supplied as methods of the file descriptor.
+
+
+<p>
+The table <code>io</code> also provides
+three predefined file descriptors with their usual meanings from C:
+<a name="pdf-io.stdin"><code>io.stdin</code></a>, <a name="pdf-io.stdout"><code>io.stdout</code></a>, and <a name="pdf-io.stderr"><code>io.stderr</code></a>.
+The I/O library never closes these files.
+
+
+<p>
+Unless otherwise stated,
+all I/O functions return <b>nil</b> on failure
+(plus an error message as a second result and
+a system-dependent error code as a third result)
+and some value different from <b>nil</b> on success.
+
+
+<p>
+<hr><h3><a name="pdf-io.close"><code>io.close ([file])</code></a></h3>
+
+
+<p>
+Equivalent to <code>file:close()</code>.
+Without a <code>file</code>, closes the default output file.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.flush"><code>io.flush ()</code></a></h3>
+
+
+<p>
+Equivalent to <code>file:flush</code> over the default output file.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.input"><code>io.input ([file])</code></a></h3>
+
+
+<p>
+When called with a file name, it opens the named file (in text mode),
+and sets its handle as the default input file.
+When called with a file handle,
+it simply sets this file handle as the default input file.
+When called without parameters,
+it returns the current default input file.
+
+
+<p>
+In case of errors this function raises the error,
+instead of returning an error code.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.lines"><code>io.lines ([filename])</code></a></h3>
+
+
+<p>
+Opens the given file name in read mode
+and returns an iterator function that,
+each time it is called,
+returns a new line from the file.
+Therefore, the construction
+
+<pre>
+     for line in io.lines(filename) do <em>body</em> end
+</pre><p>
+will iterate over all lines of the file.
+When the iterator function detects the end of file,
+it returns <b>nil</b> (to finish the loop) and automatically closes the file.
+
+
+<p>
+The call <code>io.lines()</code> (with no file name) is equivalent
+to <code>io.input():lines()</code>;
+that is, it iterates over the lines of the default input file.
+In this case it does not close the file when the loop ends.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.open"><code>io.open (filename [, mode])</code></a></h3>
+
+
+<p>
+This function opens a file,
+in the mode specified in the string <code>mode</code>.
+It returns a new file handle,
+or, in case of errors, <b>nil</b> plus an error message.
+
+
+<p>
+The <code>mode</code> string can be any of the following:
+
+<ul>
+<li><b>"r":</b> read mode (the default);</li>
+<li><b>"w":</b> write mode;</li>
+<li><b>"a":</b> append mode;</li>
+<li><b>"r+":</b> update mode, all previous data is preserved;</li>
+<li><b>"w+":</b> update mode, all previous data is erased;</li>
+<li><b>"a+":</b> append update mode, previous data is preserved,
+  writing is only allowed at the end of file.</li>
+</ul><p>
+The <code>mode</code> string may also have a '<code>b</code>' at the end,
+which is needed in some systems to open the file in binary mode.
+This string is exactly what is used in the
+standard&nbsp;C function <code>fopen</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.output"><code>io.output ([file])</code></a></h3>
+
+
+<p>
+Similar to <a href="#pdf-io.input"><code>io.input</code></a>, but operates over the default output file.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.popen"><code>io.popen (prog [, mode])</code></a></h3>
+
+
+<p>
+Starts program <code>prog</code> in a separated process and returns
+a file handle that you can use to read data from this program
+(if <code>mode</code> is <code>"r"</code>, the default)
+or to write data to this program
+(if <code>mode</code> is <code>"w"</code>).
+
+
+<p>
+This function is system dependent and is not available
+on all platforms.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.read"><code>io.read (&middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Equivalent to <code>io.input():read</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.tmpfile"><code>io.tmpfile ()</code></a></h3>
+
+
+<p>
+Returns a handle for a temporary file.
+This file is opened in update mode
+and it is automatically removed when the program ends.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.type"><code>io.type (obj)</code></a></h3>
+
+
+<p>
+Checks whether <code>obj</code> is a valid file handle.
+Returns the string <code>"file"</code> if <code>obj</code> is an open file handle,
+<code>"closed file"</code> if <code>obj</code> is a closed file handle,
+or <b>nil</b> if <code>obj</code> is not a file handle.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-io.write"><code>io.write (&middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Equivalent to <code>io.output():write</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-file:close"><code>file:close ()</code></a></h3>
+
+
+<p>
+Closes <code>file</code>.
+Note that files are automatically closed when
+their handles are garbage collected,
+but that takes an unpredictable amount of time to happen.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-file:flush"><code>file:flush ()</code></a></h3>
+
+
+<p>
+Saves any written data to <code>file</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-file:lines"><code>file:lines ()</code></a></h3>
+
+
+<p>
+Returns an iterator function that,
+each time it is called,
+returns a new line from the file.
+Therefore, the construction
+
+<pre>
+     for line in file:lines() do <em>body</em> end
+</pre><p>
+will iterate over all lines of the file.
+(Unlike <a href="#pdf-io.lines"><code>io.lines</code></a>, this function does not close the file
+when the loop ends.)
+
+
+
+
+<p>
+<hr><h3><a name="pdf-file:read"><code>file:read (&middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Reads the file <code>file</code>,
+according to the given formats, which specify what to read.
+For each format,
+the function returns a string (or a number) with the characters read,
+or <b>nil</b> if it cannot read data with the specified format.
+When called without formats,
+it uses a default format that reads the entire next line
+(see below).
+
+
+<p>
+The available formats are
+
+<ul>
+
+<li><b>"*n":</b>
+reads a number;
+this is the only format that returns a number instead of a string.
+</li>
+
+<li><b>"*a":</b>
+reads the whole file, starting at the current position.
+On end of file, it returns the empty string.
+</li>
+
+<li><b>"*l":</b>
+reads the next line (skipping the end of line),
+returning <b>nil</b> on end of file.
+This is the default format.
+</li>
+
+<li><b><em>number</em>:</b>
+reads a string with up to this number of characters,
+returning <b>nil</b> on end of file.
+If number is zero,
+it reads nothing and returns an empty string,
+or <b>nil</b> on end of file.
+</li>
+
+</ul>
+
+
+
+<p>
+<hr><h3><a name="pdf-file:seek"><code>file:seek ([whence] [, offset])</code></a></h3>
+
+
+<p>
+Sets and gets the file position,
+measured from the beginning of the file,
+to the position given by <code>offset</code> plus a base
+specified by the string <code>whence</code>, as follows:
+
+<ul>
+<li><b>"set":</b> base is position 0 (beginning of the file);</li>
+<li><b>"cur":</b> base is current position;</li>
+<li><b>"end":</b> base is end of file;</li>
+</ul><p>
+In case of success, function <code>seek</code> returns the final file position,
+measured in bytes from the beginning of the file.
+If this function fails, it returns <b>nil</b>,
+plus a string describing the error.
+
+
+<p>
+The default value for <code>whence</code> is <code>"cur"</code>,
+and for <code>offset</code> is 0.
+Therefore, the call <code>file:seek()</code> returns the current
+file position, without changing it;
+the call <code>file:seek("set")</code> sets the position to the
+beginning of the file (and returns 0);
+and the call <code>file:seek("end")</code> sets the position to the
+end of the file, and returns its size.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-file:setvbuf"><code>file:setvbuf (mode [, size])</code></a></h3>
+
+
+<p>
+Sets the buffering mode for an output file.
+There are three available modes:
+
+<ul>
+
+<li><b>"no":</b>
+no buffering; the result of any output operation appears immediately.
+</li>
+
+<li><b>"full":</b>
+full buffering; output operation is performed only
+when the buffer is full (or when you explicitly <code>flush</code> the file
+(see <a href="#pdf-io.flush"><code>io.flush</code></a>)).
+</li>
+
+<li><b>"line":</b>
+line buffering; output is buffered until a newline is output
+or there is any input from some special files
+(such as a terminal device).
+</li>
+
+</ul><p>
+For the last two cases, <code>size</code>
+specifies the size of the buffer, in bytes.
+The default is an appropriate size.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-file:write"><code>file:write (&middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Writes the value of each of its arguments to
+the <code>file</code>.
+The arguments must be strings or numbers.
+To write other values,
+use <a href="#pdf-tostring"><code>tostring</code></a> or <a href="#pdf-string.format"><code>string.format</code></a> before <code>write</code>.
+
+
+
+
+
+
+
+<h2>5.8 - <a name="5.8">Operating System Facilities</a></h2>
+
+<p>
+This library is implemented through table <a name="pdf-os"><code>os</code></a>.
+
+
+<p>
+<hr><h3><a name="pdf-os.clock"><code>os.clock ()</code></a></h3>
+
+
+<p>
+Returns an approximation of the amount in seconds of CPU time
+used by the program.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.date"><code>os.date ([format [, time]])</code></a></h3>
+
+
+<p>
+Returns a string or a table containing date and time,
+formatted according to the given string <code>format</code>.
+
+
+<p>
+If the <code>time</code> argument is present,
+this is the time to be formatted
+(see the <a href="#pdf-os.time"><code>os.time</code></a> function for a description of this value).
+Otherwise, <code>date</code> formats the current time.
+
+
+<p>
+If <code>format</code> starts with '<code>!</code>',
+then the date is formatted in Coordinated Universal Time.
+After this optional character,
+if <code>format</code> is the string "<code>*t</code>",
+then <code>date</code> returns a table with the following fields:
+<code>year</code> (four digits), <code>month</code> (1--12), <code>day</code> (1--31),
+<code>hour</code> (0--23), <code>min</code> (0--59), <code>sec</code> (0--61),
+<code>wday</code> (weekday, Sunday is&nbsp;1),
+<code>yday</code> (day of the year),
+and <code>isdst</code> (daylight saving flag, a boolean).
+
+
+<p>
+If <code>format</code> is not "<code>*t</code>",
+then <code>date</code> returns the date as a string,
+formatted according to the same rules as the C&nbsp;function <code>strftime</code>.
+
+
+<p>
+When called without arguments,
+<code>date</code> returns a reasonable date and time representation that depends on
+the host system and on the current locale
+(that is, <code>os.date()</code> is equivalent to <code>os.date("%c")</code>).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.difftime"><code>os.difftime (t2, t1)</code></a></h3>
+
+
+<p>
+Returns the number of seconds from time <code>t1</code> to time <code>t2</code>.
+In POSIX, Windows, and some other systems,
+this value is exactly <code>t2</code><em>-</em><code>t1</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.execute"><code>os.execute ([command])</code></a></h3>
+
+
+<p>
+This function is equivalent to the C&nbsp;function <code>system</code>.
+It passes <code>command</code> to be executed by an operating system shell.
+It returns a status code, which is system-dependent.
+If <code>command</code> is absent, then it returns nonzero if a shell is available
+and zero otherwise.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.exit"><code>os.exit ([code])</code></a></h3>
+
+
+<p>
+Calls the C&nbsp;function <code>exit</code>,
+with an optional <code>code</code>,
+to terminate the host program.
+The default value for <code>code</code> is the success code.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.getenv"><code>os.getenv (varname)</code></a></h3>
+
+
+<p>
+Returns the value of the process environment variable <code>varname</code>,
+or <b>nil</b> if the variable is not defined.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.remove"><code>os.remove (filename)</code></a></h3>
+
+
+<p>
+Deletes the file or directory with the given name.
+Directories must be empty to be removed.
+If this function fails, it returns <b>nil</b>,
+plus a string describing the error.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.rename"><code>os.rename (oldname, newname)</code></a></h3>
+
+
+<p>
+Renames file or directory named <code>oldname</code> to <code>newname</code>.
+If this function fails, it returns <b>nil</b>,
+plus a string describing the error.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.setlocale"><code>os.setlocale (locale [, category])</code></a></h3>
+
+
+<p>
+Sets the current locale of the program.
+<code>locale</code> is a string specifying a locale;
+<code>category</code> is an optional string describing which category to change:
+<code>"all"</code>, <code>"collate"</code>, <code>"ctype"</code>,
+<code>"monetary"</code>, <code>"numeric"</code>, or <code>"time"</code>;
+the default category is <code>"all"</code>.
+The function returns the name of the new locale,
+or <b>nil</b> if the request cannot be honored.
+
+
+<p>
+If <code>locale</code> is the empty string,
+the current locale is set to an implementation-defined native locale.
+If <code>locale</code> is the string "<code>C</code>",
+the current locale is set to the standard C locale.
+
+
+<p>
+When called with <b>nil</b> as the first argument,
+this function only returns the name of the current locale
+for the given category.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.time"><code>os.time ([table])</code></a></h3>
+
+
+<p>
+Returns the current time when called without arguments,
+or a time representing the date and time specified by the given table.
+This table must have fields <code>year</code>, <code>month</code>, and <code>day</code>,
+and may have fields <code>hour</code>, <code>min</code>, <code>sec</code>, and <code>isdst</code>
+(for a description of these fields, see the <a href="#pdf-os.date"><code>os.date</code></a> function).
+
+
+<p>
+The returned value is a number, whose meaning depends on your system.
+In POSIX, Windows, and some other systems, this number counts the number
+of seconds since some given start time (the "epoch").
+In other systems, the meaning is not specified,
+and the number returned by <code>time</code> can be used only as an argument to
+<code>date</code> and <code>difftime</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-os.tmpname"><code>os.tmpname ()</code></a></h3>
+
+
+<p>
+Returns a string with a file name that can
+be used for a temporary file.
+The file must be explicitly opened before its use
+and explicitly removed when no longer needed.
+
+
+
+
+
+
+
+<h2>5.9 - <a name="5.9">The Debug Library</a></h2>
+
+<p>
+This library provides
+the functionality of the debug interface to Lua programs.
+You should exert care when using this library.
+The functions provided here should be used exclusively for debugging
+and similar tasks, such as profiling.
+Please resist the temptation to use them as a
+usual programming tool:
+they can be very slow.
+Moreover, several of these functions
+violate some assumptions about Lua code
+(e.g., that variables local to a function
+cannot be accessed from outside or
+that userdata metatables cannot be changed by Lua code)
+and therefore can compromise otherwise secure code.
+
+
+<p>
+All functions in this library are provided
+inside the <a name="pdf-debug"><code>debug</code></a> table.
+All functions that operate over a thread
+have an optional first argument which is the
+thread to operate over.
+The default is always the current thread.
+
+
+<p>
+<hr><h3><a name="pdf-debug.debug"><code>debug.debug ()</code></a></h3>
+
+
+<p>
+Enters an interactive mode with the user,
+running each string that the user enters.
+Using simple commands and other debug facilities,
+the user can inspect global and local variables,
+change their values, evaluate expressions, and so on.
+A line containing only the word <code>cont</code> finishes this function,
+so that the caller continues its execution.
+
+
+<p>
+Note that commands for <code>debug.debug</code> are not lexically nested
+within any function, and so have no direct access to local variables.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.getfenv"><code>debug.getfenv (o)</code></a></h3>
+Returns the environment of object <code>o</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.gethook"><code>debug.gethook ([thread])</code></a></h3>
+
+
+<p>
+Returns the current hook settings of the thread, as three values:
+the current hook function, the current hook mask,
+and the current hook count
+(as set by the <a href="#pdf-debug.sethook"><code>debug.sethook</code></a> function).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.getinfo"><code>debug.getinfo ([thread,] function [, what])</code></a></h3>
+
+
+<p>
+Returns a table with information about a function.
+You can give the function directly,
+or you can give a number as the value of <code>function</code>,
+which means the function running at level <code>function</code> of the call stack
+of the given thread:
+level&nbsp;0 is the current function (<code>getinfo</code> itself);
+level&nbsp;1 is the function that called <code>getinfo</code>;
+and so on.
+If <code>function</code> is a number larger than the number of active functions,
+then <code>getinfo</code> returns <b>nil</b>.
+
+
+<p>
+The returned table may contain all the fields returned by <a href="#lua_getinfo"><code>lua_getinfo</code></a>,
+with the string <code>what</code> describing which fields to fill in.
+The default for <code>what</code> is to get all information available,
+except the table of valid lines.
+If present,
+the option '<code>f</code>'
+adds a field named <code>func</code> with the function itself.
+If present,
+the option '<code>L</code>'
+adds a field named <code>activelines</code> with the table of
+valid lines.
+
+
+<p>
+For instance, the expression <code>debug.getinfo(1,"n").name</code> returns
+a table with a name for the current function,
+if a reasonable name can be found,
+and the expression <code>debug.getinfo(print)</code>
+returns a table with all available information
+about the <a href="#pdf-print"><code>print</code></a> function.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.getlocal"><code>debug.getlocal ([thread,] level, local)</code></a></h3>
+
+
+<p>
+This function returns the name and the value of the local variable
+with index <code>local</code> of the function at level <code>level</code> of the stack.
+(The first parameter or local variable has index&nbsp;1, and so on,
+until the last active local variable.)
+The function returns <b>nil</b> if there is no local
+variable with the given index,
+and raises an error when called with a <code>level</code> out of range.
+(You can call <a href="#pdf-debug.getinfo"><code>debug.getinfo</code></a> to check whether the level is valid.)
+
+
+<p>
+Variable names starting with '<code>(</code>' (open parentheses)
+represent internal variables
+(loop control variables, temporaries, and C&nbsp;function locals).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.getmetatable"><code>debug.getmetatable (object)</code></a></h3>
+
+
+<p>
+Returns the metatable of the given <code>object</code>
+or <b>nil</b> if it does not have a metatable.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.getregistry"><code>debug.getregistry ()</code></a></h3>
+
+
+<p>
+Returns the registry table (see <a href="#3.5">&sect;3.5</a>).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.getupvalue"><code>debug.getupvalue (func, up)</code></a></h3>
+
+
+<p>
+This function returns the name and the value of the upvalue
+with index <code>up</code> of the function <code>func</code>.
+The function returns <b>nil</b> if there is no upvalue with the given index.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.setfenv"><code>debug.setfenv (object, table)</code></a></h3>
+
+
+<p>
+Sets the environment of the given <code>object</code> to the given <code>table</code>.
+Returns <code>object</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.sethook"><code>debug.sethook ([thread,] hook, mask [, count])</code></a></h3>
+
+
+<p>
+Sets the given function as a hook.
+The string <code>mask</code> and the number <code>count</code> describe
+when the hook will be called.
+The string mask may have the following characters,
+with the given meaning:
+
+<ul>
+<li><b><code>"c"</code>:</b> the hook is called every time Lua calls a function;</li>
+<li><b><code>"r"</code>:</b> the hook is called every time Lua returns from a function;</li>
+<li><b><code>"l"</code>:</b> the hook is called every time Lua enters a new line of code.</li>
+</ul><p>
+With a <code>count</code> different from zero,
+the hook is called after every <code>count</code> instructions.
+
+
+<p>
+When called without arguments,
+<a href="#pdf-debug.sethook"><code>debug.sethook</code></a> turns off the hook.
+
+
+<p>
+When the hook is called, its first parameter is a string
+describing the event that has triggered its call:
+<code>"call"</code>, <code>"return"</code> (or <code>"tail return"</code>),
+<code>"line"</code>, and <code>"count"</code>.
+For line events,
+the hook also gets the new line number as its second parameter.
+Inside a hook,
+you can call <code>getinfo</code> with level&nbsp;2 to get more information about
+the running function
+(level&nbsp;0 is the <code>getinfo</code> function,
+and level&nbsp;1 is the hook function),
+unless the event is <code>"tail return"</code>.
+In this case, Lua is only simulating the return,
+and a call to <code>getinfo</code> will return invalid data.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.setlocal"><code>debug.setlocal ([thread,] level, local, value)</code></a></h3>
+
+
+<p>
+This function assigns the value <code>value</code> to the local variable
+with index <code>local</code> of the function at level <code>level</code> of the stack.
+The function returns <b>nil</b> if there is no local
+variable with the given index,
+and raises an error when called with a <code>level</code> out of range.
+(You can call <code>getinfo</code> to check whether the level is valid.)
+Otherwise, it returns the name of the local variable.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.setmetatable"><code>debug.setmetatable (object, table)</code></a></h3>
+
+
+<p>
+Sets the metatable for the given <code>object</code> to the given <code>table</code>
+(which can be <b>nil</b>).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.setupvalue"><code>debug.setupvalue (func, up, value)</code></a></h3>
+
+
+<p>
+This function assigns the value <code>value</code> to the upvalue
+with index <code>up</code> of the function <code>func</code>.
+The function returns <b>nil</b> if there is no upvalue
+with the given index.
+Otherwise, it returns the name of the upvalue.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-debug.traceback"><code>debug.traceback ([thread,] [message] [, level])</code></a></h3>
+
+
+<p>
+Returns a string with a traceback of the call stack.
+An optional <code>message</code> string is appended
+at the beginning of the traceback.
+An optional <code>level</code> number tells at which level
+to start the traceback
+(default is 1, the function calling <code>traceback</code>).
+
+
+
+
+
+
+
+<h1>6 - <a name="6">Lua Stand-alone</a></h1>
+
+<p>
+Although Lua has been designed as an extension language,
+to be embedded in a host C&nbsp;program,
+it is also frequently used as a stand-alone language.
+An interpreter for Lua as a stand-alone language,
+called simply <code>lua</code>,
+is provided with the standard distribution.
+The stand-alone interpreter includes
+all standard libraries, including the debug library.
+Its usage is:
+
+<pre>
+     lua [options] [script [args]]
+</pre><p>
+The options are:
+
+<ul>
+<li><b><code>-e <em>stat</em></code>:</b> executes string <em>stat</em>;</li>
+<li><b><code>-l <em>mod</em></code>:</b> "requires" <em>mod</em>;</li>
+<li><b><code>-i</code>:</b> enters interactive mode after running <em>script</em>;</li>
+<li><b><code>-v</code>:</b> prints version information;</li>
+<li><b><code>--</code>:</b> stops handling options;</li>
+<li><b><code>-</code>:</b> executes <code>stdin</code> as a file and stops handling options.</li>
+</ul><p>
+After handling its options, <code>lua</code> runs the given <em>script</em>,
+passing to it the given <em>args</em> as string arguments.
+When called without arguments,
+<code>lua</code> behaves as <code>lua -v -i</code>
+when the standard input (<code>stdin</code>) is a terminal,
+and as <code>lua -</code> otherwise.
+
+
+<p>
+Before running any argument,
+the interpreter checks for an environment variable <a name="pdf-LUA_INIT"><code>LUA_INIT</code></a>.
+If its format is <code>@<em>filename</em></code>,
+then <code>lua</code> executes the file.
+Otherwise, <code>lua</code> executes the string itself.
+
+
+<p>
+All options are handled in order, except <code>-i</code>.
+For instance, an invocation like
+
+<pre>
+     $ lua -e'a=1' -e 'print(a)' script.lua
+</pre><p>
+will first set <code>a</code> to 1, then print the value of <code>a</code> (which is '<code>1</code>'),
+and finally run the file <code>script.lua</code> with no arguments.
+(Here <code>$</code> is the shell prompt. Your prompt may be different.)
+
+
+<p>
+Before starting to run the script,
+<code>lua</code> collects all arguments in the command line
+in a global table called <code>arg</code>.
+The script name is stored at index 0,
+the first argument after the script name goes to index 1,
+and so on.
+Any arguments before the script name
+(that is, the interpreter name plus the options)
+go to negative indices.
+For instance, in the call
+
+<pre>
+     $ lua -la b.lua t1 t2
+</pre><p>
+the interpreter first runs the file <code>a.lua</code>,
+then creates a table
+
+<pre>
+     arg = { [-2] = "lua", [-1] = "-la",
+             [0] = "b.lua",
+             [1] = "t1", [2] = "t2" }
+</pre><p>
+and finally runs the file <code>b.lua</code>.
+The script is called with <code>arg[1]</code>, <code>arg[2]</code>, &middot;&middot;&middot;
+as arguments;
+it can also access these arguments with the vararg expression '<code>...</code>'.
+
+
+<p>
+In interactive mode,
+if you write an incomplete statement,
+the interpreter waits for its completion
+by issuing a different prompt.
+
+
+<p>
+If the global variable <a name="pdf-_PROMPT"><code>_PROMPT</code></a> contains a string,
+then its value is used as the prompt.
+Similarly, if the global variable <a name="pdf-_PROMPT2"><code>_PROMPT2</code></a> contains a string,
+its value is used as the secondary prompt
+(issued during incomplete statements).
+Therefore, both prompts can be changed directly on the command line
+or in any Lua programs by assigning to <code>_PROMPT</code>.
+See the next example:
+
+<pre>
+     $ lua -e"_PROMPT='myprompt&gt; '" -i
+</pre><p>
+(The outer pair of quotes is for the shell,
+the inner pair is for Lua.)
+Note the use of <code>-i</code> to enter interactive mode;
+otherwise,
+the program would just end silently
+right after the assignment to <code>_PROMPT</code>.
+
+
+<p>
+To allow the use of Lua as a
+script interpreter in Unix systems,
+the stand-alone interpreter skips
+the first line of a chunk if it starts with <code>#</code>.
+Therefore, Lua scripts can be made into executable programs
+by using <code>chmod +x</code> and the&nbsp;<code>#!</code> form,
+as in
+
+<pre>
+     #!/usr/local/bin/lua
+</pre><p>
+(Of course,
+the location of the Lua interpreter may be different in your machine.
+If <code>lua</code> is in your <code>PATH</code>,
+then 
+
+<pre>
+     #!/usr/bin/env lua
+</pre><p>
+is a more portable solution.) 
+
+
+
+<h1>7 - <a name="7">Incompatibilities with the Previous Version</a></h1>
+
+<p>
+Here we list the incompatibilities that you may find when moving a program
+from Lua&nbsp;5.0 to Lua&nbsp;5.1.
+You can avoid most of the incompatibilities compiling Lua with
+appropriate options (see file <code>luaconf.h</code>).
+However,
+all these compatibility options will be removed in the next version of Lua.
+
+
+
+<h2>7.1 - <a name="7.1">Changes in the Language</a></h2>
+<ul>
+
+<li>
+The vararg system changed from the pseudo-argument <code>arg</code> with a
+table with the extra arguments to the vararg expression.
+(See compile-time option <code>LUA_COMPAT_VARARG</code> in <code>luaconf.h</code>.)
+</li>
+
+<li>
+There was a subtle change in the scope of the implicit
+variables of the <b>for</b> statement and for the <b>repeat</b> statement.
+</li>
+
+<li>
+The long string/long comment syntax (<code>[[<em>string</em>]]</code>)
+does not allow nesting.
+You can use the new syntax (<code>[=[<em>string</em>]=]</code>) in these cases.
+(See compile-time option <code>LUA_COMPAT_LSTR</code> in <code>luaconf.h</code>.)
+</li>
+
+</ul>
+
+
+
+
+<h2>7.2 - <a name="7.2">Changes in the Libraries</a></h2>
+<ul>
+
+<li>
+Function <code>string.gfind</code> was renamed <a href="#pdf-string.gmatch"><code>string.gmatch</code></a>.
+(See compile-time option <code>LUA_COMPAT_GFIND</code> in <code>luaconf.h</code>.)
+</li>
+
+<li>
+When <a href="#pdf-string.gsub"><code>string.gsub</code></a> is called with a function as its
+third argument,
+whenever this function returns <b>nil</b> or <b>false</b> the
+replacement string is the whole match,
+instead of the empty string.
+</li>
+
+<li>
+Function <code>table.setn</code> was deprecated.
+Function <code>table.getn</code> corresponds
+to the new length operator (<code>#</code>);
+use the operator instead of the function.
+(See compile-time option <code>LUA_COMPAT_GETN</code> in <code>luaconf.h</code>.)
+</li>
+
+<li>
+Function <code>loadlib</code> was renamed <a href="#pdf-package.loadlib"><code>package.loadlib</code></a>.
+(See compile-time option <code>LUA_COMPAT_LOADLIB</code> in <code>luaconf.h</code>.)
+</li>
+
+<li>
+Function <code>math.mod</code> was renamed <a href="#pdf-math.fmod"><code>math.fmod</code></a>.
+(See compile-time option <code>LUA_COMPAT_MOD</code> in <code>luaconf.h</code>.)
+</li>
+
+<li>
+Functions <code>table.foreach</code> and <code>table.foreachi</code> are deprecated.
+You can use a for loop with <code>pairs</code> or <code>ipairs</code> instead.
+</li>
+
+<li>
+There were substantial changes in function <a href="#pdf-require"><code>require</code></a> due to
+the new module system.
+However, the new behavior is mostly compatible with the old,
+but <code>require</code> gets the path from <a href="#pdf-package.path"><code>package.path</code></a> instead
+of from <code>LUA_PATH</code>.
+</li>
+
+<li>
+Function <a href="#pdf-collectgarbage"><code>collectgarbage</code></a> has different arguments.
+Function <code>gcinfo</code> is deprecated;
+use <code>collectgarbage("count")</code> instead.
+</li>
+
+</ul>
+
+
+
+
+<h2>7.3 - <a name="7.3">Changes in the API</a></h2>
+<ul>
+
+<li>
+The <code>luaopen_*</code> functions (to open libraries)
+cannot be called directly,
+like a regular C function.
+They must be called through Lua,
+like a Lua function.
+</li>
+
+<li>
+Function <code>lua_open</code> was replaced by <a href="#lua_newstate"><code>lua_newstate</code></a> to
+allow the user to set a memory-allocation function.
+You can use <a href="#luaL_newstate"><code>luaL_newstate</code></a> from the standard library to
+create a state with a standard allocation function
+(based on <code>realloc</code>).
+</li>
+
+<li>
+Functions <code>luaL_getn</code> and <code>luaL_setn</code>
+(from the auxiliary library) are deprecated.
+Use <a href="#lua_objlen"><code>lua_objlen</code></a> instead of <code>luaL_getn</code>
+and nothing instead of <code>luaL_setn</code>.
+</li>
+
+<li>
+Function <code>luaL_openlib</code> was replaced by <a href="#luaL_register"><code>luaL_register</code></a>.
+</li>
+
+<li>
+Function <code>luaL_checkudata</code> now throws an error when the given value
+is not a userdata of the expected type.
+(In Lua&nbsp;5.0 it returned <code>NULL</code>.)
+</li>
+
+</ul>
+
+
+
+
+<h1>8 - <a name="8">The Complete Syntax of Lua</a></h1>
+
+<p>
+Here is the complete syntax of Lua in extended BNF.
+(It does not describe operator precedences.)
+
+
+
+
+<pre>
+
+	chunk ::= {stat [`<b>;</b>&acute;]} [laststat [`<b>;</b>&acute;]]
+
+	block ::= chunk
+
+	stat ::=  varlist `<b>=</b>&acute; explist | 
+		 functioncall | 
+		 <b>do</b> block <b>end</b> | 
+		 <b>while</b> exp <b>do</b> block <b>end</b> | 
+		 <b>repeat</b> block <b>until</b> exp | 
+		 <b>if</b> exp <b>then</b> block {<b>elseif</b> exp <b>then</b> block} [<b>else</b> block] <b>end</b> | 
+		 <b>for</b> Name `<b>=</b>&acute; exp `<b>,</b>&acute; exp [`<b>,</b>&acute; exp] <b>do</b> block <b>end</b> | 
+		 <b>for</b> namelist <b>in</b> explist <b>do</b> block <b>end</b> | 
+		 <b>function</b> funcname funcbody | 
+		 <b>local</b> <b>function</b> Name funcbody | 
+		 <b>local</b> namelist [`<b>=</b>&acute; explist] 
+
+	laststat ::= <b>return</b> [explist] | <b>break</b>
+
+	funcname ::= Name {`<b>.</b>&acute; Name} [`<b>:</b>&acute; Name]
+
+	varlist ::= var {`<b>,</b>&acute; var}
+
+	var ::=  Name | prefixexp `<b>[</b>&acute; exp `<b>]</b>&acute; | prefixexp `<b>.</b>&acute; Name 
+
+	namelist ::= Name {`<b>,</b>&acute; Name}
+
+	explist ::= {exp `<b>,</b>&acute;} exp
+
+	exp ::=  <b>nil</b> | <b>false</b> | <b>true</b> | Number | String | `<b>...</b>&acute; | function | 
+		 prefixexp | tableconstructor | exp binop exp | unop exp 
+
+	prefixexp ::= var | functioncall | `<b>(</b>&acute; exp `<b>)</b>&acute;
+
+	functioncall ::=  prefixexp args | prefixexp `<b>:</b>&acute; Name args 
+
+	args ::=  `<b>(</b>&acute; [explist] `<b>)</b>&acute; | tableconstructor | String 
+
+	function ::= <b>function</b> funcbody
+
+	funcbody ::= `<b>(</b>&acute; [parlist] `<b>)</b>&acute; block <b>end</b>
+
+	parlist ::= namelist [`<b>,</b>&acute; `<b>...</b>&acute;] | `<b>...</b>&acute;
+
+	tableconstructor ::= `<b>{</b>&acute; [fieldlist] `<b>}</b>&acute;
+
+	fieldlist ::= field {fieldsep field} [fieldsep]
+
+	field ::= `<b>[</b>&acute; exp `<b>]</b>&acute; `<b>=</b>&acute; exp | Name `<b>=</b>&acute; exp | exp
+
+	fieldsep ::= `<b>,</b>&acute; | `<b>;</b>&acute;
+
+	binop ::= `<b>+</b>&acute; | `<b>-</b>&acute; | `<b>*</b>&acute; | `<b>/</b>&acute; | `<b>^</b>&acute; | `<b>%</b>&acute; | `<b>..</b>&acute; | 
+		 `<b>&lt;</b>&acute; | `<b>&lt;=</b>&acute; | `<b>&gt;</b>&acute; | `<b>&gt;=</b>&acute; | `<b>==</b>&acute; | `<b>~=</b>&acute; | 
+		 <b>and</b> | <b>or</b>
+
+	unop ::= `<b>-</b>&acute; | <b>not</b> | `<b>#</b>&acute;
+
+</pre>
+
+<p>
+
+
+
+
+
+
+
+<HR>
+<SMALL>
+Last update:
+Fri Jan 18 22:32:24 BRST 2008
+</SMALL>
+<!--
+Last change: revised for Lua 5.1.3
+-->
+
+</body></html>
+
diff --git a/com32/lua/doc/readme.html b/com32/lua/doc/readme.html
new file mode 100644
index 00000000..972faddd
--- /dev/null
+++ b/com32/lua/doc/readme.html
@@ -0,0 +1,40 @@
+<HTML>
+<HEAD>
+<TITLE>Lua documentation</TITLE>
+<LINK REL="stylesheet" TYPE="text/css" HREF="lua.css">
+</HEAD>
+
+<BODY>
+
+<HR>
+<H1>
+<A HREF="http://www.lua.org/"><IMG SRC="logo.gif" ALT="Lua" BORDER=0></A>
+Documentation
+</H1>
+
+This is the documentation included in the source distribution of Lua 5.1.3.
+
+<UL>
+<LI><A HREF="contents.html">Reference manual</A>
+<LI><A HREF="lua.html">lua man page</A>
+<LI><A HREF="luac.html">luac man page</A>
+<LI><A HREF="../README">lua/README</A>
+<LI><A HREF="../etc/README">lua/etc/README</A>
+<LI><A HREF="../test/README">lua/test/README</A>
+</UL>
+
+Lua's
+<A HREF="http://www.lua.org/">official web site</A>
+contains updated documentation,
+especially the
+<A HREF="http://www.lua.org/manual/5.1/">reference manual</A>.
+<P>
+
+<HR>
+<SMALL>
+Last update:
+Wed Dec 19 13:59:14 BRST 2007
+</SMALL>
+
+</BODY>
+</HTML>
diff --git a/com32/lua/etc/Makefile b/com32/lua/etc/Makefile
new file mode 100644
index 00000000..6d00008d
--- /dev/null
+++ b/com32/lua/etc/Makefile
@@ -0,0 +1,44 @@
+# makefile for Lua etc
+
+TOP= ..
+LIB= $(TOP)/src
+INC= $(TOP)/src
+BIN= $(TOP)/src
+SRC= $(TOP)/src
+TST= $(TOP)/test
+
+CC= gcc
+CFLAGS= -O2 -Wall -I$(INC) $(MYCFLAGS)
+MYCFLAGS= 
+MYLDFLAGS= -Wl,-E
+MYLIBS= -lm
+#MYLIBS= -lm -Wl,-E -ldl -lreadline -lhistory -lncurses
+RM= rm -f
+
+default:
+	@echo 'Please choose a target: min noparser one strict clean'
+
+min:	min.c
+	$(CC) $(CFLAGS) $@.c -L$(LIB) -llua $(MYLIBS)
+	echo 'print"Hello there!"' | ./a.out
+
+noparser: noparser.o
+	$(CC) noparser.o $(SRC)/lua.o -L$(LIB) -llua $(MYLIBS)
+	$(BIN)/luac $(TST)/hello.lua
+	-./a.out luac.out
+	-./a.out -e'a=1'
+
+one:
+	$(CC) $(CFLAGS) all.c $(MYLIBS)
+	./a.out $(TST)/hello.lua
+
+strict:
+	-$(BIN)/lua -e 'print(a);b=2'
+	-$(BIN)/lua -lstrict -e 'print(a)'
+	-$(BIN)/lua -e 'function f() b=2 end f()'
+	-$(BIN)/lua -lstrict -e 'function f() b=2 end f()'
+
+clean:
+	$(RM) a.out core core.* *.o luac.out
+
+.PHONY:	default min noparser one strict clean
diff --git a/com32/lua/etc/README b/com32/lua/etc/README
new file mode 100644
index 00000000..5149fc91
--- /dev/null
+++ b/com32/lua/etc/README
@@ -0,0 +1,37 @@
+This directory contains some useful files and code.
+Unlike the code in ../src, everything here is in the public domain.
+
+If any of the makes fail, you're probably not using the same libraries
+used to build Lua. Set MYLIBS in Makefile accordingly.
+
+all.c
+	Full Lua interpreter in a single file.
+	Do "make one" for a demo.
+
+lua.hpp
+	Lua header files for C++ using 'extern "C"'.
+
+lua.ico
+	A Lua icon for Windows (and web sites: save as favicon.ico).
+	Drawn by hand by Markus Gritsch <gritsch@iue.tuwien.ac.at>.
+
+lua.pc
+	pkg-config data for Lua
+
+luavs.bat
+	Script to build Lua under "Visual Studio .NET Command Prompt".
+	Run it from the toplevel as etc\luavs.bat.
+
+min.c
+	A minimal Lua interpreter.
+	Good for learning and for starting your own.
+	Do "make min" for a demo.
+
+noparser.c
+	Linking with noparser.o avoids loading the parsing modules in lualib.a.
+	Do "make noparser" for a demo.
+
+strict.lua
+	Traps uses of undeclared global variables.
+	Do "make strict" for a demo.
+
diff --git a/com32/lua/etc/all.c b/com32/lua/etc/all.c
new file mode 100644
index 00000000..dab68fac
--- /dev/null
+++ b/com32/lua/etc/all.c
@@ -0,0 +1,38 @@
+/*
+* all.c -- Lua core, libraries and interpreter in a single file
+*/
+
+#define luaall_c
+
+#include "lapi.c"
+#include "lcode.c"
+#include "ldebug.c"
+#include "ldo.c"
+#include "ldump.c"
+#include "lfunc.c"
+#include "lgc.c"
+#include "llex.c"
+#include "lmem.c"
+#include "lobject.c"
+#include "lopcodes.c"
+#include "lparser.c"
+#include "lstate.c"
+#include "lstring.c"
+#include "ltable.c"
+#include "ltm.c"
+#include "lundump.c"
+#include "lvm.c"
+#include "lzio.c"
+
+#include "lauxlib.c"
+#include "lbaselib.c"
+#include "ldblib.c"
+#include "liolib.c"
+#include "linit.c"
+#include "lmathlib.c"
+#include "loadlib.c"
+#include "loslib.c"
+#include "lstrlib.c"
+#include "ltablib.c"
+
+#include "lua.c"
diff --git a/com32/lua/etc/lua.hpp b/com32/lua/etc/lua.hpp
new file mode 100644
index 00000000..ec417f59
--- /dev/null
+++ b/com32/lua/etc/lua.hpp
@@ -0,0 +1,9 @@
+// lua.hpp
+// Lua header files for C++
+// <<extern "C">> not supplied automatically because Lua also compiles as C++
+
+extern "C" {
+#include "lua.h"
+#include "lualib.h"
+#include "lauxlib.h"
+}
diff --git a/com32/lua/etc/lua.ico b/com32/lua/etc/lua.ico
new file mode 100644
index 00000000..ccbabc4e
--- /dev/null
+++ b/com32/lua/etc/lua.ico
diff --git a/com32/lua/etc/lua.pc b/com32/lua/etc/lua.pc
new file mode 100644
index 00000000..19a5c915
--- /dev/null
+++ b/com32/lua/etc/lua.pc
@@ -0,0 +1,31 @@
+# lua.pc -- pkg-config data for Lua
+
+# vars from install Makefile
+
+# grep '^V=' ../Makefile
+V= 5.1
+# grep '^R=' ../Makefile
+R= 5.1.3
+
+# grep '^INSTALL_.*=' ../Makefile | sed 's/INSTALL_TOP/prefix/'
+prefix= /usr/local
+INSTALL_BIN= ${prefix}/bin
+INSTALL_INC= ${prefix}/include
+INSTALL_LIB= ${prefix}/lib
+INSTALL_MAN= ${prefix}/man/man1
+INSTALL_LMOD= ${prefix}/share/lua/${V}
+INSTALL_CMOD= ${prefix}/lib/lua/${V}
+
+# canonical vars
+exec_prefix=${prefix}
+libdir=${exec_prefix}/lib
+includedir=${prefix}/include
+
+Name: Lua
+Description: An Extensible Extension Language
+Version: ${R}
+Requires: 
+Libs: -L${libdir} -llua -lm
+Cflags: -I${includedir}
+
+# (end of lua.pc)
diff --git a/com32/lua/etc/luavs.bat b/com32/lua/etc/luavs.bat
new file mode 100644
index 00000000..08c2bedd
--- /dev/null
+++ b/com32/lua/etc/luavs.bat
@@ -0,0 +1,28 @@
+@rem Script to build Lua under "Visual Studio .NET Command Prompt".

+@rem Do not run from this directory; run it from the toplevel: etc\luavs.bat .

+@rem It creates lua51.dll, lua51.lib, lua.exe, and luac.exe in src.

+@rem (contributed by David Manura and Mike Pall)

+

+@setlocal

+@set MYCOMPILE=cl /nologo /MD /O2 /W3 /c /D_CRT_SECURE_NO_DEPRECATE

+@set MYLINK=link /nologo

+@set MYMT=mt /nologo

+

+cd src

+%MYCOMPILE% /DLUA_BUILD_AS_DLL l*.c

+del lua.obj luac.obj

+%MYLINK% /DLL /out:lua51.dll l*.obj

+if exist lua51.dll.manifest^

+  %MYMT% -manifest lua51.dll.manifest -outputresource:lua51.dll;2

+%MYCOMPILE% /DLUA_BUILD_AS_DLL lua.c

+%MYLINK% /out:lua.exe lua.obj lua51.lib

+if exist lua.exe.manifest^

+  %MYMT% -manifest lua.exe.manifest -outputresource:lua.exe

+%MYCOMPILE% l*.c print.c

+del lua.obj linit.obj lbaselib.obj ldblib.obj liolib.obj lmathlib.obj^

+    loslib.obj ltablib.obj lstrlib.obj loadlib.obj

+%MYLINK% /out:luac.exe *.obj

+if exist luac.exe.manifest^

+  %MYMT% -manifest luac.exe.manifest -outputresource:luac.exe

+del *.obj *.manifest

+cd ..

diff --git a/com32/lua/etc/min.c b/com32/lua/etc/min.c
new file mode 100644
index 00000000..6a85a4d1
--- /dev/null
+++ b/com32/lua/etc/min.c
@@ -0,0 +1,39 @@
+/*
+* min.c -- a minimal Lua interpreter
+* loads stdin only with minimal error handling.
+* no interaction, and no standard library, only a "print" function.
+*/
+
+#include <stdio.h>
+
+#include "lua.h"
+#include "lauxlib.h"
+
+static int print(lua_State *L)
+{
+ int n=lua_gettop(L);
+ int i;
+ for (i=1; i<=n; i++)
+ {
+  if (i>1) printf("\t");
+  if (lua_isstring(L,i))
+   printf("%s",lua_tostring(L,i));
+  else if (lua_isnil(L,i))
+   printf("%s","nil");
+  else if (lua_isboolean(L,i))
+   printf("%s",lua_toboolean(L,i) ? "true" : "false");
+  else
+   printf("%s:%p",luaL_typename(L,i),lua_topointer(L,i));
+ }
+ printf("\n");
+ return 0;
+}
+
+int main(void)
+{
+ lua_State *L=lua_open();
+ lua_register(L,"print",print);
+ if (luaL_dofile(L,NULL)!=0) fprintf(stderr,"%s\n",lua_tostring(L,-1));
+ lua_close(L);
+ return 0;
+}
diff --git a/com32/lua/etc/noparser.c b/com32/lua/etc/noparser.c
new file mode 100644
index 00000000..13ba5462
--- /dev/null
+++ b/com32/lua/etc/noparser.c
@@ -0,0 +1,50 @@
+/*
+* The code below can be used to make a Lua core that does not contain the
+* parsing modules (lcode, llex, lparser), which represent 35% of the total core.
+* You'll only be able to load binary files and strings, precompiled with luac.
+* (Of course, you'll have to build luac with the original parsing modules!)
+*
+* To use this module, simply compile it ("make noparser" does that) and list
+* its object file before the Lua libraries. The linker should then not load
+* the parsing modules. To try it, do "make luab".
+*
+* If you also want to avoid the dump module (ldump.o), define NODUMP.
+* #define NODUMP
+*/
+
+#define LUA_CORE
+
+#include "llex.h"
+#include "lparser.h"
+#include "lzio.h"
+
+LUAI_FUNC void luaX_init (lua_State *L) {
+  UNUSED(L);
+}
+
+LUAI_FUNC Proto *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff, const char *name) {
+  UNUSED(z);
+  UNUSED(buff);
+  UNUSED(name);
+  lua_pushliteral(L,"parser not loaded");
+  lua_error(L);
+  return NULL;
+}
+
+#ifdef NODUMP
+#include "lundump.h"
+
+LUAI_FUNC int luaU_dump (lua_State* L, const Proto* f, lua_Writer w, void* data, int strip) {
+  UNUSED(f);
+  UNUSED(w);
+  UNUSED(data);
+  UNUSED(strip);
+#if 1
+  UNUSED(L);
+  return 0;
+#else
+  lua_pushliteral(L,"dumper not loaded");
+  lua_error(L);
+#endif
+}
+#endif
diff --git a/com32/lua/etc/strict.lua b/com32/lua/etc/strict.lua
new file mode 100644
index 00000000..604619dd
--- /dev/null
+++ b/com32/lua/etc/strict.lua
@@ -0,0 +1,41 @@
+--
+-- strict.lua
+-- checks uses of undeclared global variables
+-- All global variables must be 'declared' through a regular assignment
+-- (even assigning nil will do) in a main chunk before being used
+-- anywhere or assigned to inside a function.
+--
+
+local getinfo, error, rawset, rawget = debug.getinfo, error, rawset, rawget
+
+local mt = getmetatable(_G)
+if mt == nil then
+  mt = {}
+  setmetatable(_G, mt)
+end
+
+mt.__declared = {}
+
+local function what ()
+  local d = getinfo(3, "S")
+  return d and d.what or "C"
+end
+
+mt.__newindex = function (t, n, v)
+  if not mt.__declared[n] then
+    local w = what()
+    if w ~= "main" and w ~= "C" then
+      error("assign to undeclared variable '"..n.."'", 2)
+    end
+    mt.__declared[n] = true
+  end
+  rawset(t, n, v)
+end
+  
+mt.__index = function (t, n)
+  if not mt.__declared[n] and what() ~= "C" then
+    error("variable '"..n.."' is not declared", 2)
+  end
+  return rawget(t, n)
+end
+
diff --git a/com32/lua/src/Makefile b/com32/lua/src/Makefile
new file mode 100644
index 00000000..72f2a2a7
--- /dev/null
+++ b/com32/lua/src/Makefile
@@ -0,0 +1,111 @@
+## -----------------------------------------------------------------------
+##
+##   Copyright 2001-2008 H. Peter Anvin - All Rights Reserved
+##
+##   This program is free software; you can redistribute it and/or modify
+##   it under the terms of the GNU General Public License as published by
+##   the Free Software Foundation, Inc., 53 Temple Place Ste 330,
+##   Boston MA 02111-1307, USA; either version 2 of the License, or
+##   (at your option) any later version; incorporated herein by reference.
+##
+## -----------------------------------------------------------------------
+
+##
+## samples for syslinux users
+##
+
+TMPFILE = $(shell mktemp /tmp/gcc_ok.XXXXXX)
+CC	= gcc
+
+gcc_ok   = $(shell tmpf=$(TMPFILE); if $(CC) $(1) -c -x c /dev/null -o $$tmpf 2>/dev/null; \
+	           then echo $(1); else echo $(2); fi; rm -f $$tmpf)
+
+M32     := $(call gcc_ok,-m32,) $(call gcc_ok,-fno-stack-protector,)
+
+LD         = ld -m elf_i386
+AR	   = ar
+NASM	   = nasm
+NASMOPT	   = -O9999
+RANLIB	   = ranlib
+CFLAGS     = $(M32) -mregparm=3 -DREGPARM=3 -W -Wall -march=i386 -Os \
+	     -fomit-frame-pointer -D__COM32__ \
+	     -nostdinc -iwithprefix include \
+	     -I../../libutil/include -I../../include \
+	     -I../../gplinclude \
+	     -Wp,-MT,$@,-MD,$(dir $@).$(notdir $@).d
+LNXCFLAGS  = -W -Wall -O -g -I../../libutil/include
+LNXSFLAGS  = -g
+LNXLDFLAGS = -g
+SFLAGS     = -D__COM32__ -march=i386
+LDFLAGS    = -T ../../lib/com32.ld
+OBJCOPY    = objcopy
+LIBGCC    := $(shell $(CC) --print-libgcc)
+LIBS	   = liblua.a ../../libutil/libutil_com.a \
+		../../gpllib/libcom32gpl.a  \
+		../../lib/libcom32.a $(LIBGCC)
+LNXLIBS	   = ../../libutil/libutil_lnx.a
+
+.SUFFIXES: .lss .c .o .elf .c32 .lnx
+
+LIBLUA_OBJS := lapi.o lcode.o ldebug.o ldo.o ldump.o lfunc.o
+LIBLUA_OBJS += lgc.o llex.o lmem.o  lobject.o lopcodes.o lparser.o
+LIBLUA_OBJS += lstate.o lstring.o ltable.o ltm.o lvm.o lzio.o lundump.o
+LIBLUA_OBJS += syslinux.o
+
+LIBLUA_OBJS += lauxlib.o lbaselib.o ldblib.o  ltablib.o \
+	lstrlib.o loadlib.o linit.o
+LIBLUA_OBJS += liolib.o
+LIBLUA_OBJS += dmi.o
+
+CFLAGS += -DLUA_ANSI
+
+all:	liblua.a lua.c32
+
+liblua.a: $(LIBLUA_OBJS)
+	$(AR) cq $@ $^
+	$(RANLIB) $@
+
+lua.elf: lua.o liblua.a
+	$(LD) --emit-relocs $(LDFLAGS) -o $@ lua.o $(LIBS) $(LNXLIBS)
+
+
+.PRECIOUS: %.o
+%.o: %.S
+	$(CC) $(SFLAGS) -c -o $@ $<
+
+.PRECIOUS: %.o
+%.o: %.c
+	$(CC) $(CFLAGS) -c -o $@ $<
+
+.PRECIOUS: %.elf
+%.elf: %.o $(LIBS)
+	$(LD) $(LDFLAGS) -o $@ $^
+
+.PRECIOUS: %.lo
+%.lo: %.S
+	$(CC) $(LNXSFLAGS) -c -o $@ $<
+
+.PRECIOUS: %.lo
+%.lo: %.c
+	$(CC) $(LNXCFLAGS) -c -o $@ $<
+
+.PRECIOUS: %.lnx
+%.lnx: %.lo $(LNXLIBS)
+	$(CC) $(LNXLDFLAGS) -o $@ $^
+
+%.c32: %.elf
+	$(OBJCOPY) -O binary $< $@
+	../../tools/relocs $< >> $@ || ( rm -f $@ ; false )
+
+tidy dist:
+	rm -f *.o *.lo *.a *.lst *.elf .*.d
+
+clean: tidy
+	rm -f *.lss *.c32 *.lnx *.com
+
+spotless: clean
+	rm -f *~ \#*
+
+install:	# Don't install samples
+
+-include .*.d
diff --git a/com32/lua/src/Makefile-orig b/com32/lua/src/Makefile-orig
new file mode 100644
index 00000000..e4a3cd61
--- /dev/null
+++ b/com32/lua/src/Makefile-orig
@@ -0,0 +1,182 @@
+# makefile for building Lua
+# see ../INSTALL for installation instructions
+# see ../Makefile and luaconf.h for further customization
+
+# == CHANGE THE SETTINGS BELOW TO SUIT YOUR ENVIRONMENT =======================
+
+# Your platform. See PLATS for possible values.
+PLAT= none
+
+CC= gcc
+CFLAGS= -O2 -Wall $(MYCFLAGS)
+AR= ar rcu
+RANLIB= ranlib
+RM= rm -f
+LIBS= -lm $(MYLIBS)
+
+MYCFLAGS=
+MYLDFLAGS=
+MYLIBS=
+
+# == END OF USER SETTINGS. NO NEED TO CHANGE ANYTHING BELOW THIS LINE =========
+
+PLATS= aix ansi bsd freebsd generic linux macosx mingw posix solaris
+
+LUA_A=	liblua.a
+CORE_O=	lapi.o lcode.o ldebug.o ldo.o ldump.o lfunc.o lgc.o llex.o lmem.o \
+	lobject.o lopcodes.o lparser.o lstate.o lstring.o ltable.o ltm.o  \
+	lundump.o lvm.o lzio.o
+LIB_O=	lauxlib.o lbaselib.o ldblib.o liolib.o lmathlib.o loslib.o ltablib.o \
+	lstrlib.o loadlib.o linit.o
+
+LUA_T=	lua
+LUA_O=	lua.o
+
+LUAC_T=	luac
+LUAC_O=	luac.o print.o
+
+ALL_O= $(CORE_O) $(LIB_O) $(LUA_O) $(LUAC_O)
+ALL_T= $(LUA_A) $(LUA_T) $(LUAC_T)
+ALL_A= $(LUA_A)
+
+default: $(PLAT)
+
+all:	$(ALL_T)
+
+o:	$(ALL_O)
+
+a:	$(ALL_A)
+
+$(LUA_A): $(CORE_O) $(LIB_O)
+	$(AR) $@ $?
+	$(RANLIB) $@
+
+$(LUA_T): $(LUA_O) $(LUA_A)
+	$(CC) -o $@ $(MYLDFLAGS) $(LUA_O) $(LUA_A) $(LIBS)
+
+$(LUAC_T): $(LUAC_O) $(LUA_A)
+	$(CC) -o $@ $(MYLDFLAGS) $(LUAC_O) $(LUA_A) $(LIBS)
+
+clean:
+	$(RM) $(ALL_T) $(ALL_O)
+
+depend:
+	@$(CC) $(CFLAGS) -MM l*.c print.c
+
+echo:
+	@echo "PLAT = $(PLAT)"
+	@echo "CC = $(CC)"
+	@echo "CFLAGS = $(CFLAGS)"
+	@echo "AR = $(AR)"
+	@echo "RANLIB = $(RANLIB)"
+	@echo "RM = $(RM)"
+	@echo "MYCFLAGS = $(MYCFLAGS)"
+	@echo "MYLDFLAGS = $(MYLDFLAGS)"
+	@echo "MYLIBS = $(MYLIBS)"
+
+# convenience targets for popular platforms
+
+none:
+	@echo "Please choose a platform:"
+	@echo "   $(PLATS)"
+
+aix:
+	$(MAKE) all CC="xlc" CFLAGS="-O2 -DLUA_USE_POSIX -DLUA_USE_DLOPEN" MYLIBS="-ldl" MYLDFLAGS="-brtl -bexpall"
+
+ansi:
+	$(MAKE) all MYCFLAGS=-DLUA_ANSI
+
+bsd:
+	$(MAKE) all MYCFLAGS="-DLUA_USE_POSIX -DLUA_USE_DLOPEN" MYLIBS="-Wl,-E"
+
+freebsd:
+	$(MAKE) all MYCFLAGS="-DLUA_USE_LINUX" MYLIBS="-Wl,-E -lreadline"
+
+generic:
+	$(MAKE) all MYCFLAGS=
+
+linux:
+	$(MAKE) all MYCFLAGS=-DLUA_USE_LINUX MYLIBS="-Wl,-E -ldl -lreadline -lhistory -lncurses"
+
+macosx:
+	$(MAKE) all MYCFLAGS=-DLUA_USE_LINUX MYLIBS="-lreadline"
+# use this on Mac OS X 10.3-
+#	$(MAKE) all MYCFLAGS=-DLUA_USE_MACOSX
+
+mingw:
+	$(MAKE) "LUA_A=lua51.dll" "LUA_T=lua.exe" \
+	"AR=$(CC) -shared -o" "RANLIB=strip --strip-unneeded" \
+	"MYCFLAGS=-DLUA_BUILD_AS_DLL" "MYLIBS=" "MYLDFLAGS=-s" lua.exe
+	$(MAKE) "LUAC_T=luac.exe" luac.exe
+
+posix:
+	$(MAKE) all MYCFLAGS=-DLUA_USE_POSIX
+
+solaris:
+	$(MAKE) all MYCFLAGS="-DLUA_USE_POSIX -DLUA_USE_DLOPEN" MYLIBS="-ldl"
+
+# list targets that do not create files (but not all makes understand .PHONY)
+.PHONY: all $(PLATS) default o a clean depend echo none
+
+# DO NOT DELETE
+
+lapi.o: lapi.c lua.h luaconf.h lapi.h lobject.h llimits.h ldebug.h \
+  lstate.h ltm.h lzio.h lmem.h ldo.h lfunc.h lgc.h lstring.h ltable.h \
+  lundump.h lvm.h
+lauxlib.o: lauxlib.c lua.h luaconf.h lauxlib.h
+lbaselib.o: lbaselib.c lua.h luaconf.h lauxlib.h lualib.h
+lcode.o: lcode.c lua.h luaconf.h lcode.h llex.h lobject.h llimits.h \
+  lzio.h lmem.h lopcodes.h lparser.h ldebug.h lstate.h ltm.h ldo.h lgc.h \
+  ltable.h
+ldblib.o: ldblib.c lua.h luaconf.h lauxlib.h lualib.h
+ldebug.o: ldebug.c lua.h luaconf.h lapi.h lobject.h llimits.h lcode.h \
+  llex.h lzio.h lmem.h lopcodes.h lparser.h ldebug.h lstate.h ltm.h ldo.h \
+  lfunc.h lstring.h lgc.h ltable.h lvm.h
+ldo.o: ldo.c lua.h luaconf.h ldebug.h lstate.h lobject.h llimits.h ltm.h \
+  lzio.h lmem.h ldo.h lfunc.h lgc.h lopcodes.h lparser.h lstring.h \
+  ltable.h lundump.h lvm.h
+ldump.o: ldump.c lua.h luaconf.h lobject.h llimits.h lstate.h ltm.h \
+  lzio.h lmem.h lundump.h
+lfunc.o: lfunc.c lua.h luaconf.h lfunc.h lobject.h llimits.h lgc.h lmem.h \
+  lstate.h ltm.h lzio.h
+lgc.o: lgc.c lua.h luaconf.h ldebug.h lstate.h lobject.h llimits.h ltm.h \
+  lzio.h lmem.h ldo.h lfunc.h lgc.h lstring.h ltable.h
+linit.o: linit.c lua.h luaconf.h lualib.h lauxlib.h
+liolib.o: liolib.c lua.h luaconf.h lauxlib.h lualib.h
+llex.o: llex.c lua.h luaconf.h ldo.h lobject.h llimits.h lstate.h ltm.h \
+  lzio.h lmem.h llex.h lparser.h lstring.h lgc.h ltable.h
+lmathlib.o: lmathlib.c lua.h luaconf.h lauxlib.h lualib.h
+lmem.o: lmem.c lua.h luaconf.h ldebug.h lstate.h lobject.h llimits.h \
+  ltm.h lzio.h lmem.h ldo.h
+loadlib.o: loadlib.c lua.h luaconf.h lauxlib.h lualib.h
+lobject.o: lobject.c lua.h luaconf.h ldo.h lobject.h llimits.h lstate.h \
+  ltm.h lzio.h lmem.h lstring.h lgc.h lvm.h
+lopcodes.o: lopcodes.c lopcodes.h llimits.h lua.h luaconf.h
+loslib.o: loslib.c lua.h luaconf.h lauxlib.h lualib.h
+lparser.o: lparser.c lua.h luaconf.h lcode.h llex.h lobject.h llimits.h \
+  lzio.h lmem.h lopcodes.h lparser.h ldebug.h lstate.h ltm.h ldo.h \
+  lfunc.h lstring.h lgc.h ltable.h
+lstate.o: lstate.c lua.h luaconf.h ldebug.h lstate.h lobject.h llimits.h \
+  ltm.h lzio.h lmem.h ldo.h lfunc.h lgc.h llex.h lstring.h ltable.h
+lstring.o: lstring.c lua.h luaconf.h lmem.h llimits.h lobject.h lstate.h \
+  ltm.h lzio.h lstring.h lgc.h
+lstrlib.o: lstrlib.c lua.h luaconf.h lauxlib.h lualib.h
+ltable.o: ltable.c lua.h luaconf.h ldebug.h lstate.h lobject.h llimits.h \
+  ltm.h lzio.h lmem.h ldo.h lgc.h ltable.h
+ltablib.o: ltablib.c lua.h luaconf.h lauxlib.h lualib.h
+ltm.o: ltm.c lua.h luaconf.h lobject.h llimits.h lstate.h ltm.h lzio.h \
+  lmem.h lstring.h lgc.h ltable.h
+lua.o: lua.c lua.h luaconf.h lauxlib.h lualib.h
+luac.o: luac.c lua.h luaconf.h lauxlib.h ldo.h lobject.h llimits.h \
+  lstate.h ltm.h lzio.h lmem.h lfunc.h lopcodes.h lstring.h lgc.h \
+  lundump.h
+lundump.o: lundump.c lua.h luaconf.h ldebug.h lstate.h lobject.h \
+  llimits.h ltm.h lzio.h lmem.h ldo.h lfunc.h lstring.h lgc.h lundump.h
+lvm.o: lvm.c lua.h luaconf.h ldebug.h lstate.h lobject.h llimits.h ltm.h \
+  lzio.h lmem.h ldo.h lfunc.h lgc.h lopcodes.h lstring.h ltable.h lvm.h
+lzio.o: lzio.c lua.h luaconf.h llimits.h lmem.h lstate.h lobject.h ltm.h \
+  lzio.h
+print.o: print.c ldebug.h lstate.h lua.h luaconf.h lobject.h llimits.h \
+  ltm.h lzio.h lmem.h lopcodes.h lundump.h
+
+# (end of Makefile)
diff --git a/com32/lua/src/dmi.c b/com32/lua/src/dmi.c
new file mode 100644
index 00000000..0c89ea9a
--- /dev/null
+++ b/com32/lua/src/dmi.c
@@ -0,0 +1,303 @@
+#include <stdlib.h>
+#include <string.h>
+
+#define ldmilib_c       /* Define the library */
+
+/* Include the Lua API header files */
+#include "lua.h"
+#include "lauxlib.h"
+#include "lualib.h"
+#include "dmi/dmi.h"
+
+static int dmi_gettable(lua_State *L)
+{
+  s_dmi dmi;
+
+  lua_newtable(L);
+
+  /* FIXME initalize *dmi */
+  if ( ! dmi_iterate(&dmi) ) {
+          printf("No DMI Structure found\n");
+          return -1;
+  }
+
+  parse_dmitable(&dmi);
+
+  /* bios */
+  lua_pushstring(L, "bios.vendor");
+  lua_pushstring(L, dmi.bios.vendor);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "bios.version");
+  lua_pushstring(L, dmi.bios.version);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "bios.release_date");
+  lua_pushstring(L, dmi.bios.release_date);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "bios.bios_revision");
+  lua_pushstring(L, dmi.bios.bios_revision);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "bios.firmware_revision");
+  lua_pushstring(L, dmi.bios.firmware_revision);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "bios.address");
+  lua_pushnumber(L, dmi.bios.address);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "bios.runtime_size");
+  lua_pushnumber(L, dmi.bios.runtime_size);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "bios.runtime_size_unit");
+  lua_pushstring(L, dmi.bios.runtime_size_unit);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "bios.rom_size");
+  lua_pushnumber(L, dmi.bios.rom_size);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "bios.rom_size_unit");
+  lua_pushstring(L, dmi.bios.rom_size_unit);
+  lua_settable(L,-3);
+
+  /* system */
+  lua_pushstring(L, "system.manufacturer");
+  lua_pushstring(L, dmi.system.manufacturer);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "system.product_name");
+  lua_pushstring(L, dmi.system.product_name);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "system.version");
+  lua_pushstring(L, dmi.system.version);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "system.serial");
+  lua_pushstring(L, dmi.system.serial);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "system.uuid");
+  lua_pushstring(L, dmi.system.uuid);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "system.wakeup_type");
+  lua_pushstring(L, dmi.system.wakeup_type);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "system.sku_number");
+  lua_pushstring(L, dmi.system.sku_number);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "system.family");
+  lua_pushstring(L, dmi.system.family);
+  lua_settable(L,-3);
+
+  /* base_board */
+  lua_pushstring(L, "base_board.manufacturer");
+  lua_pushstring(L, dmi.base_board.manufacturer);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "base_board.product_name");
+  lua_pushstring(L, dmi.base_board.product_name);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "base_board.version");
+  lua_pushstring(L, dmi.base_board.version);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "base_board.serial");
+  lua_pushstring(L, dmi.base_board.serial);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "base_board.asset_tag");
+  lua_pushstring(L, dmi.base_board.asset_tag);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "base_board.location");
+  lua_pushstring(L, dmi.base_board.location);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "base_board.type");
+  lua_pushstring(L, dmi.base_board.type);
+  lua_settable(L,-3);
+
+  /* chassis */
+  lua_pushstring(L, "chassis.manufacturer");
+  lua_pushstring(L, dmi.chassis.manufacturer);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "chassis.type");
+  lua_pushstring(L, dmi.chassis.type);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "chassis.lock");
+  lua_pushstring(L, dmi.chassis.lock);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "chassis.version");
+  lua_pushstring(L, dmi.chassis.version);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "chassis.serial");
+  lua_pushstring(L, dmi.chassis.serial);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "chassis.asset_tag");
+  lua_pushstring(L, dmi.chassis.asset_tag);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "chassis.boot_up_state");
+  lua_pushstring(L, dmi.chassis.boot_up_state);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "chassis.power_supply_state");
+  lua_pushstring(L, dmi.chassis.power_supply_state);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "chassis.thermal_state");
+  lua_pushstring(L, dmi.chassis.thermal_state);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "chassis.security_status");
+  lua_pushstring(L, dmi.chassis.security_status);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "chassis.oem_information");
+  lua_pushstring(L, dmi.chassis.oem_information);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "chassis.height");
+  lua_pushnumber(L, dmi.chassis.height);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "chassis.nb_power_cords");
+  lua_pushnumber(L, dmi.chassis.nb_power_cords);
+  lua_settable(L,-3);
+
+  /* processor */
+  lua_pushstring(L, "processor.socket_designation");
+  lua_pushstring(L, dmi.processor.socket_designation);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.type");
+  lua_pushstring(L, dmi.processor.type);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.family");
+  lua_pushstring(L, dmi.processor.family);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.manufacturer");
+  lua_pushstring(L, dmi.processor.manufacturer);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.version");
+  lua_pushstring(L, dmi.processor.version);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.external_clock");
+  lua_pushnumber(L, dmi.processor.external_clock);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.max_speed");
+  lua_pushnumber(L, dmi.processor.max_speed);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.current_speed");
+  lua_pushnumber(L, dmi.processor.current_speed);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.signature.type");
+  lua_pushnumber(L, dmi.processor.signature.type);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.signature.family");
+  lua_pushnumber(L, dmi.processor.signature.family);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.signature.model");
+  lua_pushnumber(L, dmi.processor.signature.model);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.signature.stepping");
+  lua_pushnumber(L, dmi.processor.signature.stepping);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.signature.minor_stepping");
+  lua_pushnumber(L, dmi.processor.signature.minor_stepping);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.voltage_mv");
+  lua_pushnumber(L, dmi.processor.voltage_mv);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.status");
+  lua_pushstring(L, dmi.processor.status);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.upgrade");
+  lua_pushstring(L, dmi.processor.upgrade);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.cache1");
+  lua_pushstring(L, dmi.processor.cache1);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.cache2");
+  lua_pushstring(L, dmi.processor.cache2);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.cache3");
+  lua_pushstring(L, dmi.processor.cache3);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.serial");
+  lua_pushstring(L, dmi.processor.serial);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.part_number");
+  lua_pushstring(L, dmi.processor.part_number);
+  lua_settable(L,-3);
+
+  lua_pushstring(L, "processor.id");
+  lua_pushstring(L, dmi.processor.id);
+  lua_settable(L,-3);
+
+  /* set global variable: lua_setglobal(L, "dmitable"); */
+
+  /* return number of return values on stack */
+  return 1;
+}
+
+
+static int dmi_supported(lua_State *L)
+{
+  s_dmi dmi;
+
+  /* FIXME initalize *dmi */
+  if ( dmi_iterate(&dmi) ) {
+    lua_pushboolean(L, 1);
+  } else {
+    lua_pushboolean(L, 0);
+  }
+  return 1;
+}
+
+
+static const luaL_Reg dmilib[] = {
+  {"gettable", dmi_gettable},
+  {"supported", dmi_supported},
+  {NULL, NULL}
+};
+
+
+LUALIB_API int luaopen_dmi (lua_State *L) {
+  luaL_openlib(L, LUA_DMILIBNAME, dmilib, 0);
+  return 1;
+}
+
diff --git a/com32/lua/src/lapi.c b/com32/lua/src/lapi.c
new file mode 100644
index 00000000..d7e8931e
--- /dev/null
+++ b/com32/lua/src/lapi.c
@@ -0,0 +1,1085 @@
+/*
+** $Id: lapi.c,v 2.55.1.3 2008/01/03 15:20:39 roberto Exp $
+** Lua API
+** See Copyright Notice in lua.h
+*/
+
+
+#include <assert.h>
+#include <math.h>
+#include <stdarg.h>
+#include <string.h>
+
+#define lapi_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "lapi.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+#include "lundump.h"
+#include "lvm.h"
+
+
+
+const char lua_ident[] =
+  "$Lua: " LUA_RELEASE " " LUA_COPYRIGHT " $\n"
+  "$Authors: " LUA_AUTHORS " $\n"
+  "$URL: www.lua.org $\n";
+
+
+
+#define api_checknelems(L, n)	api_check(L, (n) <= (L->top - L->base))
+
+#define api_checkvalidindex(L, i)	api_check(L, (i) != luaO_nilobject)
+
+#define api_incr_top(L)   {api_check(L, L->top < L->ci->top); L->top++;}
+
+
+
+static TValue *index2adr (lua_State *L, int idx) {
+  if (idx > 0) {
+    TValue *o = L->base + (idx - 1);
+    api_check(L, idx <= L->ci->top - L->base);
+    if (o >= L->top) return cast(TValue *, luaO_nilobject);
+    else return o;
+  }
+  else if (idx > LUA_REGISTRYINDEX) {
+    api_check(L, idx != 0 && -idx <= L->top - L->base);
+    return L->top + idx;
+  }
+  else switch (idx) {  /* pseudo-indices */
+    case LUA_REGISTRYINDEX: return registry(L);
+    case LUA_ENVIRONINDEX: {
+      Closure *func = curr_func(L);
+      sethvalue(L, &L->env, func->c.env);
+      return &L->env;
+    }
+    case LUA_GLOBALSINDEX: return gt(L);
+    default: {
+      Closure *func = curr_func(L);
+      idx = LUA_GLOBALSINDEX - idx;
+      return (idx <= func->c.nupvalues)
+                ? &func->c.upvalue[idx-1]
+                : cast(TValue *, luaO_nilobject);
+    }
+  }
+}
+
+
+static Table *getcurrenv (lua_State *L) {
+  if (L->ci == L->base_ci)  /* no enclosing function? */
+    return hvalue(gt(L));  /* use global table as environment */
+  else {
+    Closure *func = curr_func(L);
+    return func->c.env;
+  }
+}
+
+
+void luaA_pushobject (lua_State *L, const TValue *o) {
+  setobj2s(L, L->top, o);
+  api_incr_top(L);
+}
+
+
+LUA_API int lua_checkstack (lua_State *L, int size) {
+  int res;
+  lua_lock(L);
+  if ((L->top - L->base + size) > LUAI_MAXCSTACK)
+    res = 0;  /* stack overflow */
+  else {
+    luaD_checkstack(L, size);
+    if (L->ci->top < L->top + size)
+      L->ci->top = L->top + size;
+    res = 1;
+  }
+  lua_unlock(L);
+  return res;
+}
+
+
+LUA_API void lua_xmove (lua_State *from, lua_State *to, int n) {
+  int i;
+  if (from == to) return;
+  lua_lock(to);
+  api_checknelems(from, n);
+  api_check(from, G(from) == G(to));
+  api_check(from, to->ci->top - to->top >= n);
+  from->top -= n;
+  for (i = 0; i < n; i++) {
+    setobj2s(to, to->top++, from->top + i);
+  }
+  lua_unlock(to);
+}
+
+
+LUA_API void lua_setlevel (lua_State *from, lua_State *to) {
+  to->nCcalls = from->nCcalls;
+}
+
+
+LUA_API lua_CFunction lua_atpanic (lua_State *L, lua_CFunction panicf) {
+  lua_CFunction old;
+  lua_lock(L);
+  old = G(L)->panic;
+  G(L)->panic = panicf;
+  lua_unlock(L);
+  return old;
+}
+
+
+LUA_API lua_State *lua_newthread (lua_State *L) {
+  lua_State *L1;
+  lua_lock(L);
+  luaC_checkGC(L);
+  L1 = luaE_newthread(L);
+  setthvalue(L, L->top, L1);
+  api_incr_top(L);
+  lua_unlock(L);
+  luai_userstatethread(L, L1);
+  return L1;
+}
+
+
+
+/*
+** basic stack manipulation
+*/
+
+
+LUA_API int lua_gettop (lua_State *L) {
+  return cast_int(L->top - L->base);
+}
+
+
+LUA_API void lua_settop (lua_State *L, int idx) {
+  lua_lock(L);
+  if (idx >= 0) {
+    api_check(L, idx <= L->stack_last - L->base);
+    while (L->top < L->base + idx)
+      setnilvalue(L->top++);
+    L->top = L->base + idx;
+  }
+  else {
+    api_check(L, -(idx+1) <= (L->top - L->base));
+    L->top += idx+1;  /* `subtract' index (index is negative) */
+  }
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_remove (lua_State *L, int idx) {
+  StkId p;
+  lua_lock(L);
+  p = index2adr(L, idx);
+  api_checkvalidindex(L, p);
+  while (++p < L->top) setobjs2s(L, p-1, p);
+  L->top--;
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_insert (lua_State *L, int idx) {
+  StkId p;
+  StkId q;
+  lua_lock(L);
+  p = index2adr(L, idx);
+  api_checkvalidindex(L, p);
+  for (q = L->top; q>p; q--) setobjs2s(L, q, q-1);
+  setobjs2s(L, p, L->top);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_replace (lua_State *L, int idx) {
+  StkId o;
+  lua_lock(L);
+  /* explicit test for incompatible code */
+  if (idx == LUA_ENVIRONINDEX && L->ci == L->base_ci)
+    luaG_runerror(L, "no calling environment");
+  api_checknelems(L, 1);
+  o = index2adr(L, idx);
+  api_checkvalidindex(L, o);
+  if (idx == LUA_ENVIRONINDEX) {
+    Closure *func = curr_func(L);
+    api_check(L, ttistable(L->top - 1)); 
+    func->c.env = hvalue(L->top - 1);
+    luaC_barrier(L, func, L->top - 1);
+  }
+  else {
+    setobj(L, o, L->top - 1);
+    if (idx < LUA_GLOBALSINDEX)  /* function upvalue? */
+      luaC_barrier(L, curr_func(L), L->top - 1);
+  }
+  L->top--;
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushvalue (lua_State *L, int idx) {
+  lua_lock(L);
+  setobj2s(L, L->top, index2adr(L, idx));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+
+/*
+** access functions (stack -> C)
+*/
+
+
+LUA_API int lua_type (lua_State *L, int idx) {
+  StkId o = index2adr(L, idx);
+  return (o == luaO_nilobject) ? LUA_TNONE : ttype(o);
+}
+
+
+LUA_API const char *lua_typename (lua_State *L, int t) {
+  UNUSED(L);
+  return (t == LUA_TNONE) ? "no value" : luaT_typenames[t];
+}
+
+
+LUA_API int lua_iscfunction (lua_State *L, int idx) {
+  StkId o = index2adr(L, idx);
+  return iscfunction(o);
+}
+
+
+LUA_API int lua_isnumber (lua_State *L, int idx) {
+  TValue n;
+  const TValue *o = index2adr(L, idx);
+  return tonumber(o, &n);
+}
+
+
+LUA_API int lua_isstring (lua_State *L, int idx) {
+  int t = lua_type(L, idx);
+  return (t == LUA_TSTRING || t == LUA_TNUMBER);
+}
+
+
+LUA_API int lua_isuserdata (lua_State *L, int idx) {
+  const TValue *o = index2adr(L, idx);
+  return (ttisuserdata(o) || ttislightuserdata(o));
+}
+
+
+LUA_API int lua_rawequal (lua_State *L, int index1, int index2) {
+  StkId o1 = index2adr(L, index1);
+  StkId o2 = index2adr(L, index2);
+  return (o1 == luaO_nilobject || o2 == luaO_nilobject) ? 0
+         : luaO_rawequalObj(o1, o2);
+}
+
+
+LUA_API int lua_equal (lua_State *L, int index1, int index2) {
+  StkId o1, o2;
+  int i;
+  lua_lock(L);  /* may call tag method */
+  o1 = index2adr(L, index1);
+  o2 = index2adr(L, index2);
+  i = (o1 == luaO_nilobject || o2 == luaO_nilobject) ? 0 : equalobj(L, o1, o2);
+  lua_unlock(L);
+  return i;
+}
+
+
+LUA_API int lua_lessthan (lua_State *L, int index1, int index2) {
+  StkId o1, o2;
+  int i;
+  lua_lock(L);  /* may call tag method */
+  o1 = index2adr(L, index1);
+  o2 = index2adr(L, index2);
+  i = (o1 == luaO_nilobject || o2 == luaO_nilobject) ? 0
+       : luaV_lessthan(L, o1, o2);
+  lua_unlock(L);
+  return i;
+}
+
+
+
+LUA_API lua_Number lua_tonumber (lua_State *L, int idx) {
+  TValue n;
+  const TValue *o = index2adr(L, idx);
+  if (tonumber(o, &n))
+    return nvalue(o);
+  else
+    return 0;
+}
+
+
+LUA_API lua_Integer lua_tointeger (lua_State *L, int idx) {
+  TValue n;
+  const TValue *o = index2adr(L, idx);
+  if (tonumber(o, &n)) {
+    lua_Integer res;
+    lua_Number num = nvalue(o);
+    lua_number2integer(res, num);
+    return res;
+  }
+  else
+    return 0;
+}
+
+
+LUA_API int lua_toboolean (lua_State *L, int idx) {
+  const TValue *o = index2adr(L, idx);
+  return !l_isfalse(o);
+}
+
+
+LUA_API const char *lua_tolstring (lua_State *L, int idx, size_t *len) {
+  StkId o = index2adr(L, idx);
+  if (!ttisstring(o)) {
+    lua_lock(L);  /* `luaV_tostring' may create a new string */
+    if (!luaV_tostring(L, o)) {  /* conversion failed? */
+      if (len != NULL) *len = 0;
+      lua_unlock(L);
+      return NULL;
+    }
+    luaC_checkGC(L);
+    o = index2adr(L, idx);  /* previous call may reallocate the stack */
+    lua_unlock(L);
+  }
+  if (len != NULL) *len = tsvalue(o)->len;
+  return svalue(o);
+}
+
+
+LUA_API size_t lua_objlen (lua_State *L, int idx) {
+  StkId o = index2adr(L, idx);
+  switch (ttype(o)) {
+    case LUA_TSTRING: return tsvalue(o)->len;
+    case LUA_TUSERDATA: return uvalue(o)->len;
+    case LUA_TTABLE: return luaH_getn(hvalue(o));
+    case LUA_TNUMBER: {
+      size_t l;
+      lua_lock(L);  /* `luaV_tostring' may create a new string */
+      l = (luaV_tostring(L, o) ? tsvalue(o)->len : 0);
+      lua_unlock(L);
+      return l;
+    }
+    default: return 0;
+  }
+}
+
+
+LUA_API lua_CFunction lua_tocfunction (lua_State *L, int idx) {
+  StkId o = index2adr(L, idx);
+  return (!iscfunction(o)) ? NULL : clvalue(o)->c.f;
+}
+
+
+LUA_API void *lua_touserdata (lua_State *L, int idx) {
+  StkId o = index2adr(L, idx);
+  switch (ttype(o)) {
+    case LUA_TUSERDATA: return (rawuvalue(o) + 1);
+    case LUA_TLIGHTUSERDATA: return pvalue(o);
+    default: return NULL;
+  }
+}
+
+
+LUA_API lua_State *lua_tothread (lua_State *L, int idx) {
+  StkId o = index2adr(L, idx);
+  return (!ttisthread(o)) ? NULL : thvalue(o);
+}
+
+
+LUA_API const void *lua_topointer (lua_State *L, int idx) {
+  StkId o = index2adr(L, idx);
+  switch (ttype(o)) {
+    case LUA_TTABLE: return hvalue(o);
+    case LUA_TFUNCTION: return clvalue(o);
+    case LUA_TTHREAD: return thvalue(o);
+    case LUA_TUSERDATA:
+    case LUA_TLIGHTUSERDATA:
+      return lua_touserdata(L, idx);
+    default: return NULL;
+  }
+}
+
+
+
+/*
+** push functions (C -> stack)
+*/
+
+
+LUA_API void lua_pushnil (lua_State *L) {
+  lua_lock(L);
+  setnilvalue(L->top);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushnumber (lua_State *L, lua_Number n) {
+  lua_lock(L);
+  setnvalue(L->top, n);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushinteger (lua_State *L, lua_Integer n) {
+  lua_lock(L);
+  setnvalue(L->top, cast_num(n));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushlstring (lua_State *L, const char *s, size_t len) {
+  lua_lock(L);
+  luaC_checkGC(L);
+  setsvalue2s(L, L->top, luaS_newlstr(L, s, len));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushstring (lua_State *L, const char *s) {
+  if (s == NULL)
+    lua_pushnil(L);
+  else
+    lua_pushlstring(L, s, strlen(s));
+}
+
+
+LUA_API const char *lua_pushvfstring (lua_State *L, const char *fmt,
+                                      va_list argp) {
+  const char *ret;
+  lua_lock(L);
+  luaC_checkGC(L);
+  ret = luaO_pushvfstring(L, fmt, argp);
+  lua_unlock(L);
+  return ret;
+}
+
+
+LUA_API const char *lua_pushfstring (lua_State *L, const char *fmt, ...) {
+  const char *ret;
+  va_list argp;
+  lua_lock(L);
+  luaC_checkGC(L);
+  va_start(argp, fmt);
+  ret = luaO_pushvfstring(L, fmt, argp);
+  va_end(argp);
+  lua_unlock(L);
+  return ret;
+}
+
+
+LUA_API void lua_pushcclosure (lua_State *L, lua_CFunction fn, int n) {
+  Closure *cl;
+  lua_lock(L);
+  luaC_checkGC(L);
+  api_checknelems(L, n);
+  cl = luaF_newCclosure(L, n, getcurrenv(L));
+  cl->c.f = fn;
+  L->top -= n;
+  while (n--)
+    setobj2n(L, &cl->c.upvalue[n], L->top+n);
+  setclvalue(L, L->top, cl);
+  lua_assert(iswhite(obj2gco(cl)));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushboolean (lua_State *L, int b) {
+  lua_lock(L);
+  setbvalue(L->top, (b != 0));  /* ensure that true is 1 */
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushlightuserdata (lua_State *L, void *p) {
+  lua_lock(L);
+  setpvalue(L->top, p);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API int lua_pushthread (lua_State *L) {
+  lua_lock(L);
+  setthvalue(L, L->top, L);
+  api_incr_top(L);
+  lua_unlock(L);
+  return (G(L)->mainthread == L);
+}
+
+
+
+/*
+** get functions (Lua -> stack)
+*/
+
+
+LUA_API void lua_gettable (lua_State *L, int idx) {
+  StkId t;
+  lua_lock(L);
+  t = index2adr(L, idx);
+  api_checkvalidindex(L, t);
+  luaV_gettable(L, t, L->top - 1, L->top - 1);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_getfield (lua_State *L, int idx, const char *k) {
+  StkId t;
+  TValue key;
+  lua_lock(L);
+  t = index2adr(L, idx);
+  api_checkvalidindex(L, t);
+  setsvalue(L, &key, luaS_new(L, k));
+  luaV_gettable(L, t, &key, L->top);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_rawget (lua_State *L, int idx) {
+  StkId t;
+  lua_lock(L);
+  t = index2adr(L, idx);
+  api_check(L, ttistable(t));
+  setobj2s(L, L->top - 1, luaH_get(hvalue(t), L->top - 1));
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_rawgeti (lua_State *L, int idx, int n) {
+  StkId o;
+  lua_lock(L);
+  o = index2adr(L, idx);
+  api_check(L, ttistable(o));
+  setobj2s(L, L->top, luaH_getnum(hvalue(o), n));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_createtable (lua_State *L, int narray, int nrec) {
+  lua_lock(L);
+  luaC_checkGC(L);
+  sethvalue(L, L->top, luaH_new(L, narray, nrec));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API int lua_getmetatable (lua_State *L, int objindex) {
+  const TValue *obj;
+  Table *mt = NULL;
+  int res;
+  lua_lock(L);
+  obj = index2adr(L, objindex);
+  switch (ttype(obj)) {
+    case LUA_TTABLE:
+      mt = hvalue(obj)->metatable;
+      break;
+    case LUA_TUSERDATA:
+      mt = uvalue(obj)->metatable;
+      break;
+    default:
+      mt = G(L)->mt[ttype(obj)];
+      break;
+  }
+  if (mt == NULL)
+    res = 0;
+  else {
+    sethvalue(L, L->top, mt);
+    api_incr_top(L);
+    res = 1;
+  }
+  lua_unlock(L);
+  return res;
+}
+
+
+LUA_API void lua_getfenv (lua_State *L, int idx) {
+  StkId o;
+  lua_lock(L);
+  o = index2adr(L, idx);
+  api_checkvalidindex(L, o);
+  switch (ttype(o)) {
+    case LUA_TFUNCTION:
+      sethvalue(L, L->top, clvalue(o)->c.env);
+      break;
+    case LUA_TUSERDATA:
+      sethvalue(L, L->top, uvalue(o)->env);
+      break;
+    case LUA_TTHREAD:
+      setobj2s(L, L->top,  gt(thvalue(o)));
+      break;
+    default:
+      setnilvalue(L->top);
+      break;
+  }
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+/*
+** set functions (stack -> Lua)
+*/
+
+
+LUA_API void lua_settable (lua_State *L, int idx) {
+  StkId t;
+  lua_lock(L);
+  api_checknelems(L, 2);
+  t = index2adr(L, idx);
+  api_checkvalidindex(L, t);
+  luaV_settable(L, t, L->top - 2, L->top - 1);
+  L->top -= 2;  /* pop index and value */
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_setfield (lua_State *L, int idx, const char *k) {
+  StkId t;
+  TValue key;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  t = index2adr(L, idx);
+  api_checkvalidindex(L, t);
+  setsvalue(L, &key, luaS_new(L, k));
+  luaV_settable(L, t, &key, L->top - 1);
+  L->top--;  /* pop value */
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_rawset (lua_State *L, int idx) {
+  StkId t;
+  lua_lock(L);
+  api_checknelems(L, 2);
+  t = index2adr(L, idx);
+  api_check(L, ttistable(t));
+  setobj2t(L, luaH_set(L, hvalue(t), L->top-2), L->top-1);
+  luaC_barriert(L, hvalue(t), L->top-1);
+  L->top -= 2;
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_rawseti (lua_State *L, int idx, int n) {
+  StkId o;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  o = index2adr(L, idx);
+  api_check(L, ttistable(o));
+  setobj2t(L, luaH_setnum(L, hvalue(o), n), L->top-1);
+  luaC_barriert(L, hvalue(o), L->top-1);
+  L->top--;
+  lua_unlock(L);
+}
+
+
+LUA_API int lua_setmetatable (lua_State *L, int objindex) {
+  TValue *obj;
+  Table *mt;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  obj = index2adr(L, objindex);
+  api_checkvalidindex(L, obj);
+  if (ttisnil(L->top - 1))
+    mt = NULL;
+  else {
+    api_check(L, ttistable(L->top - 1));
+    mt = hvalue(L->top - 1);
+  }
+  switch (ttype(obj)) {
+    case LUA_TTABLE: {
+      hvalue(obj)->metatable = mt;
+      if (mt)
+        luaC_objbarriert(L, hvalue(obj), mt);
+      break;
+    }
+    case LUA_TUSERDATA: {
+      uvalue(obj)->metatable = mt;
+      if (mt)
+        luaC_objbarrier(L, rawuvalue(obj), mt);
+      break;
+    }
+    default: {
+      G(L)->mt[ttype(obj)] = mt;
+      break;
+    }
+  }
+  L->top--;
+  lua_unlock(L);
+  return 1;
+}
+
+
+LUA_API int lua_setfenv (lua_State *L, int idx) {
+  StkId o;
+  int res = 1;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  o = index2adr(L, idx);
+  api_checkvalidindex(L, o);
+  api_check(L, ttistable(L->top - 1));
+  switch (ttype(o)) {
+    case LUA_TFUNCTION:
+      clvalue(o)->c.env = hvalue(L->top - 1);
+      break;
+    case LUA_TUSERDATA:
+      uvalue(o)->env = hvalue(L->top - 1);
+      break;
+    case LUA_TTHREAD:
+      sethvalue(L, gt(thvalue(o)), hvalue(L->top - 1));
+      break;
+    default:
+      res = 0;
+      break;
+  }
+  if (res) luaC_objbarrier(L, gcvalue(o), hvalue(L->top - 1));
+  L->top--;
+  lua_unlock(L);
+  return res;
+}
+
+
+/*
+** `load' and `call' functions (run Lua code)
+*/
+
+
+#define adjustresults(L,nres) \
+    { if (nres == LUA_MULTRET && L->top >= L->ci->top) L->ci->top = L->top; }
+
+
+#define checkresults(L,na,nr) \
+     api_check(L, (nr) == LUA_MULTRET || (L->ci->top - L->top >= (nr) - (na)))
+	
+
+LUA_API void lua_call (lua_State *L, int nargs, int nresults) {
+  StkId func;
+  lua_lock(L);
+  api_checknelems(L, nargs+1);
+  checkresults(L, nargs, nresults);
+  func = L->top - (nargs+1);
+  luaD_call(L, func, nresults);
+  adjustresults(L, nresults);
+  lua_unlock(L);
+}
+
+
+
+/*
+** Execute a protected call.
+*/
+struct CallS {  /* data to `f_call' */
+  StkId func;
+  int nresults;
+};
+
+
+static void f_call (lua_State *L, void *ud) {
+  struct CallS *c = cast(struct CallS *, ud);
+  luaD_call(L, c->func, c->nresults);
+}
+
+
+
+LUA_API int lua_pcall (lua_State *L, int nargs, int nresults, int errfunc) {
+  struct CallS c;
+  int status;
+  ptrdiff_t func;
+  lua_lock(L);
+  api_checknelems(L, nargs+1);
+  checkresults(L, nargs, nresults);
+  if (errfunc == 0)
+    func = 0;
+  else {
+    StkId o = index2adr(L, errfunc);
+    api_checkvalidindex(L, o);
+    func = savestack(L, o);
+  }
+  c.func = L->top - (nargs+1);  /* function to be called */
+  c.nresults = nresults;
+  status = luaD_pcall(L, f_call, &c, savestack(L, c.func), func);
+  adjustresults(L, nresults);
+  lua_unlock(L);
+  return status;
+}
+
+
+/*
+** Execute a protected C call.
+*/
+struct CCallS {  /* data to `f_Ccall' */
+  lua_CFunction func;
+  void *ud;
+};
+
+
+static void f_Ccall (lua_State *L, void *ud) {
+  struct CCallS *c = cast(struct CCallS *, ud);
+  Closure *cl;
+  cl = luaF_newCclosure(L, 0, getcurrenv(L));
+  cl->c.f = c->func;
+  setclvalue(L, L->top, cl);  /* push function */
+  api_incr_top(L);
+  setpvalue(L->top, c->ud);  /* push only argument */
+  api_incr_top(L);
+  luaD_call(L, L->top - 2, 0);
+}
+
+
+LUA_API int lua_cpcall (lua_State *L, lua_CFunction func, void *ud) {
+  struct CCallS c;
+  int status;
+  lua_lock(L);
+  c.func = func;
+  c.ud = ud;
+  status = luaD_pcall(L, f_Ccall, &c, savestack(L, L->top), 0);
+  lua_unlock(L);
+  return status;
+}
+
+
+LUA_API int lua_load (lua_State *L, lua_Reader reader, void *data,
+                      const char *chunkname) {
+  ZIO z;
+  int status;
+  lua_lock(L);
+  if (!chunkname) chunkname = "?";
+  luaZ_init(L, &z, reader, data);
+  status = luaD_protectedparser(L, &z, chunkname);
+  lua_unlock(L);
+  return status;
+}
+
+
+LUA_API int lua_dump (lua_State *L, lua_Writer writer, void *data) {
+  int status;
+  TValue *o;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  o = L->top - 1;
+  if (isLfunction(o))
+    status = luaU_dump(L, clvalue(o)->l.p, writer, data, 0);
+  else
+    status = 1;
+  lua_unlock(L);
+  return status;
+}
+
+
+LUA_API int  lua_status (lua_State *L) {
+  return L->status;
+}
+
+
+/*
+** Garbage-collection function
+*/
+
+LUA_API int lua_gc (lua_State *L, int what, int data) {
+  int res = 0;
+  global_State *g;
+  lua_lock(L);
+  g = G(L);
+  switch (what) {
+    case LUA_GCSTOP: {
+      g->GCthreshold = MAX_LUMEM;
+      break;
+    }
+    case LUA_GCRESTART: {
+      g->GCthreshold = g->totalbytes;
+      break;
+    }
+    case LUA_GCCOLLECT: {
+      luaC_fullgc(L);
+      break;
+    }
+    case LUA_GCCOUNT: {
+      /* GC values are expressed in Kbytes: #bytes/2^10 */
+      res = cast_int(g->totalbytes >> 10);
+      break;
+    }
+    case LUA_GCCOUNTB: {
+      res = cast_int(g->totalbytes & 0x3ff);
+      break;
+    }
+    case LUA_GCSTEP: {
+      lu_mem a = (cast(lu_mem, data) << 10);
+      if (a <= g->totalbytes)
+        g->GCthreshold = g->totalbytes - a;
+      else
+        g->GCthreshold = 0;
+      while (g->GCthreshold <= g->totalbytes)
+        luaC_step(L);
+      if (g->gcstate == GCSpause)  /* end of cycle? */
+        res = 1;  /* signal it */
+      break;
+    }
+    case LUA_GCSETPAUSE: {
+      res = g->gcpause;
+      g->gcpause = data;
+      break;
+    }
+    case LUA_GCSETSTEPMUL: {
+      res = g->gcstepmul;
+      g->gcstepmul = data;
+      break;
+    }
+    default: res = -1;  /* invalid option */
+  }
+  lua_unlock(L);
+  return res;
+}
+
+
+
+/*
+** miscellaneous functions
+*/
+
+
+LUA_API int lua_error (lua_State *L) {
+  lua_lock(L);
+  api_checknelems(L, 1);
+  luaG_errormsg(L);
+  lua_unlock(L);
+  return 0;  /* to avoid warnings */
+}
+
+
+LUA_API int lua_next (lua_State *L, int idx) {
+  StkId t;
+  int more;
+  lua_lock(L);
+  t = index2adr(L, idx);
+  api_check(L, ttistable(t));
+  more = luaH_next(L, hvalue(t), L->top - 1);
+  if (more) {
+    api_incr_top(L);
+  }
+  else  /* no more elements */
+    L->top -= 1;  /* remove key */
+  lua_unlock(L);
+  return more;
+}
+
+
+LUA_API void lua_concat (lua_State *L, int n) {
+  lua_lock(L);
+  api_checknelems(L, n);
+  if (n >= 2) {
+    luaC_checkGC(L);
+    luaV_concat(L, n, cast_int(L->top - L->base) - 1);
+    L->top -= (n-1);
+  }
+  else if (n == 0) {  /* push empty string */
+    setsvalue2s(L, L->top, luaS_newlstr(L, "", 0));
+    api_incr_top(L);
+  }
+  /* else n == 1; nothing to do */
+  lua_unlock(L);
+}
+
+
+LUA_API lua_Alloc lua_getallocf (lua_State *L, void **ud) {
+  lua_Alloc f;
+  lua_lock(L);
+  if (ud) *ud = G(L)->ud;
+  f = G(L)->frealloc;
+  lua_unlock(L);
+  return f;
+}
+
+
+LUA_API void lua_setallocf (lua_State *L, lua_Alloc f, void *ud) {
+  lua_lock(L);
+  G(L)->ud = ud;
+  G(L)->frealloc = f;
+  lua_unlock(L);
+}
+
+
+LUA_API void *lua_newuserdata (lua_State *L, size_t size) {
+  Udata *u;
+  lua_lock(L);
+  luaC_checkGC(L);
+  u = luaS_newudata(L, size, getcurrenv(L));
+  setuvalue(L, L->top, u);
+  api_incr_top(L);
+  lua_unlock(L);
+  return u + 1;
+}
+
+
+
+
+static const char *aux_upvalue (StkId fi, int n, TValue **val) {
+  Closure *f;
+  if (!ttisfunction(fi)) return NULL;
+  f = clvalue(fi);
+  if (f->c.isC) {
+    if (!(1 <= n && n <= f->c.nupvalues)) return NULL;
+    *val = &f->c.upvalue[n-1];
+    return "";
+  }
+  else {
+    Proto *p = f->l.p;
+    if (!(1 <= n && n <= p->sizeupvalues)) return NULL;
+    *val = f->l.upvals[n-1]->v;
+    return getstr(p->upvalues[n-1]);
+  }
+}
+
+
+LUA_API const char *lua_getupvalue (lua_State *L, int funcindex, int n) {
+  const char *name;
+  TValue *val;
+  lua_lock(L);
+  name = aux_upvalue(index2adr(L, funcindex), n, &val);
+  if (name) {
+    setobj2s(L, L->top, val);
+    api_incr_top(L);
+  }
+  lua_unlock(L);
+  return name;
+}
+
+
+LUA_API const char *lua_setupvalue (lua_State *L, int funcindex, int n) {
+  const char *name;
+  TValue *val;
+  StkId fi;
+  lua_lock(L);
+  fi = index2adr(L, funcindex);
+  api_checknelems(L, 1);
+  name = aux_upvalue(fi, n, &val);
+  if (name) {
+    L->top--;
+    setobj(L, val, L->top);
+    luaC_barrier(L, clvalue(fi), L->top);
+  }
+  lua_unlock(L);
+  return name;
+}
+
diff --git a/com32/lua/src/lapi.h b/com32/lua/src/lapi.h
new file mode 100644
index 00000000..2c3fab24
--- /dev/null
+++ b/com32/lua/src/lapi.h
@@ -0,0 +1,16 @@
+/*
+** $Id: lapi.h,v 2.2.1.1 2007/12/27 13:02:25 roberto Exp $
+** Auxiliary functions from Lua API
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lapi_h
+#define lapi_h
+
+
+#include "lobject.h"
+
+
+LUAI_FUNC void luaA_pushobject (lua_State *L, const TValue *o);
+
+#endif
diff --git a/com32/lua/src/lauxlib.c b/com32/lua/src/lauxlib.c
new file mode 100644
index 00000000..de528bc0
--- /dev/null
+++ b/com32/lua/src/lauxlib.c
@@ -0,0 +1,654 @@
+/*
+** $Id: lauxlib.c,v 1.159.1.3 2008/01/21 13:20:51 roberto Exp $
+** Auxiliary functions for building Lua libraries
+** See Copyright Notice in lua.h
+*/
+
+
+#include <ctype.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+/* This file uses only the official API of Lua.
+** Any function declared here could be written as an application function.
+*/
+
+#define lauxlib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+
+
+#define FREELIST_REF	0	/* free list of references */
+
+
+/* convert a stack index to positive */
+#define abs_index(L, i)		((i) > 0 || (i) <= LUA_REGISTRYINDEX ? (i) : \
+					lua_gettop(L) + (i) + 1)
+
+
+/*
+** {======================================================
+** Error-report functions
+** =======================================================
+*/
+
+
+LUALIB_API int luaL_argerror (lua_State *L, int narg, const char *extramsg) {
+  lua_Debug ar;
+  if (!lua_getstack(L, 0, &ar))  /* no stack frame? */
+    return luaL_error(L, "bad argument #%d (%s)", narg, extramsg);
+  lua_getinfo(L, "n", &ar);
+  if (strcmp(ar.namewhat, "method") == 0) {
+    narg--;  /* do not count `self' */
+    if (narg == 0)  /* error is in the self argument itself? */
+      return luaL_error(L, "calling " LUA_QS " on bad self (%s)",
+                           ar.name, extramsg);
+  }
+  if (ar.name == NULL)
+    ar.name = "?";
+  return luaL_error(L, "bad argument #%d to " LUA_QS " (%s)",
+                        narg, ar.name, extramsg);
+}
+
+
+LUALIB_API int luaL_typerror (lua_State *L, int narg, const char *tname) {
+  const char *msg = lua_pushfstring(L, "%s expected, got %s",
+                                    tname, luaL_typename(L, narg));
+  return luaL_argerror(L, narg, msg);
+}
+
+
+static void tag_error (lua_State *L, int narg, int tag) {
+  luaL_typerror(L, narg, lua_typename(L, tag));
+}
+
+
+LUALIB_API void luaL_where (lua_State *L, int level) {
+  lua_Debug ar;
+  if (lua_getstack(L, level, &ar)) {  /* check function at level */
+    lua_getinfo(L, "Sl", &ar);  /* get info about it */
+    if (ar.currentline > 0) {  /* is there info? */
+      lua_pushfstring(L, "%s:%d: ", ar.short_src, ar.currentline);
+      return;
+    }
+  }
+  lua_pushliteral(L, "");  /* else, no information available... */
+}
+
+
+LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...) {
+  va_list argp;
+  va_start(argp, fmt);
+  luaL_where(L, 1);
+  lua_pushvfstring(L, fmt, argp);
+  va_end(argp);
+  lua_concat(L, 2);
+  return lua_error(L);
+}
+
+/* }====================================================== */
+
+
+LUALIB_API int luaL_checkoption (lua_State *L, int narg, const char *def,
+                                 const char *const lst[]) {
+  const char *name = (def) ? luaL_optstring(L, narg, def) :
+                             luaL_checkstring(L, narg);
+  int i;
+  for (i=0; lst[i]; i++)
+    if (strcmp(lst[i], name) == 0)
+      return i;
+  return luaL_argerror(L, narg,
+                       lua_pushfstring(L, "invalid option " LUA_QS, name));
+}
+
+
+LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) {
+  lua_getfield(L, LUA_REGISTRYINDEX, tname);  /* get registry.name */
+  if (!lua_isnil(L, -1))  /* name already in use? */
+    return 0;  /* leave previous value on top, but return 0 */
+  lua_pop(L, 1);
+  lua_newtable(L);  /* create metatable */
+  lua_pushvalue(L, -1);
+  lua_setfield(L, LUA_REGISTRYINDEX, tname);  /* registry.name = metatable */
+  return 1;
+}
+
+
+LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) {
+  void *p = lua_touserdata(L, ud);
+  if (p != NULL) {  /* value is a userdata? */
+    if (lua_getmetatable(L, ud)) {  /* does it have a metatable? */
+      lua_getfield(L, LUA_REGISTRYINDEX, tname);  /* get correct metatable */
+      if (lua_rawequal(L, -1, -2)) {  /* does it have the correct mt? */
+        lua_pop(L, 2);  /* remove both metatables */
+        return p;
+      }
+    }
+  }
+  luaL_typerror(L, ud, tname);  /* else error */
+  return NULL;  /* to avoid warnings */
+}
+
+
+LUALIB_API void luaL_checkstack (lua_State *L, int space, const char *mes) {
+  if (!lua_checkstack(L, space))
+    luaL_error(L, "stack overflow (%s)", mes);
+}
+
+
+LUALIB_API void luaL_checktype (lua_State *L, int narg, int t) {
+  if (lua_type(L, narg) != t)
+    tag_error(L, narg, t);
+}
+
+
+LUALIB_API void luaL_checkany (lua_State *L, int narg) {
+  if (lua_type(L, narg) == LUA_TNONE)
+    luaL_argerror(L, narg, "value expected");
+}
+
+
+LUALIB_API const char *luaL_checklstring (lua_State *L, int narg, size_t *len) {
+  const char *s = lua_tolstring(L, narg, len);
+  if (!s) tag_error(L, narg, LUA_TSTRING);
+  return s;
+}
+
+
+LUALIB_API const char *luaL_optlstring (lua_State *L, int narg,
+                                        const char *def, size_t *len) {
+  if (lua_isnoneornil(L, narg)) {
+    if (len)
+      *len = (def ? strlen(def) : 0);
+    return def;
+  }
+  else return luaL_checklstring(L, narg, len);
+}
+
+
+LUALIB_API lua_Number luaL_checknumber (lua_State *L, int narg) {
+  lua_Number d = lua_tonumber(L, narg);
+  if (d == 0 && !lua_isnumber(L, narg))  /* avoid extra test when d is not 0 */
+    tag_error(L, narg, LUA_TNUMBER);
+  return d;
+}
+
+
+LUALIB_API lua_Number luaL_optnumber (lua_State *L, int narg, lua_Number def) {
+  return luaL_opt(L, luaL_checknumber, narg, def);
+}
+
+
+LUALIB_API lua_Integer luaL_checkinteger (lua_State *L, int narg) {
+  lua_Integer d = lua_tointeger(L, narg);
+  if (d == 0 && !lua_isnumber(L, narg))  /* avoid extra test when d is not 0 */
+    tag_error(L, narg, LUA_TNUMBER);
+  return d;
+}
+
+
+LUALIB_API lua_Integer luaL_optinteger (lua_State *L, int narg,
+                                                      lua_Integer def) {
+  return luaL_opt(L, luaL_checkinteger, narg, def);
+}
+
+
+LUALIB_API int luaL_getmetafield (lua_State *L, int obj, const char *event) {
+  if (!lua_getmetatable(L, obj))  /* no metatable? */
+    return 0;
+  lua_pushstring(L, event);
+  lua_rawget(L, -2);
+  if (lua_isnil(L, -1)) {
+    lua_pop(L, 2);  /* remove metatable and metafield */
+    return 0;
+  }
+  else {
+    lua_remove(L, -2);  /* remove only metatable */
+    return 1;
+  }
+}
+
+
+LUALIB_API int luaL_callmeta (lua_State *L, int obj, const char *event) {
+  obj = abs_index(L, obj);
+  if (!luaL_getmetafield(L, obj, event))  /* no metafield? */
+    return 0;
+  lua_pushvalue(L, obj);
+  lua_call(L, 1, 1);
+  return 1;
+}
+
+
+LUALIB_API void (luaL_register) (lua_State *L, const char *libname,
+                                const luaL_Reg *l) {
+  luaI_openlib(L, libname, l, 0);
+}
+
+
+static int libsize (const luaL_Reg *l) {
+  int size = 0;
+  for (; l->name; l++) size++;
+  return size;
+}
+
+
+LUALIB_API void luaI_openlib (lua_State *L, const char *libname,
+                              const luaL_Reg *l, int nup) {
+  if (libname) {
+    int size = libsize(l);
+    /* check whether lib already exists */
+    luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 1);
+    lua_getfield(L, -1, libname);  /* get _LOADED[libname] */
+    if (!lua_istable(L, -1)) {  /* not found? */
+      lua_pop(L, 1);  /* remove previous result */
+      /* try global variable (and create one if it does not exist) */
+      if (luaL_findtable(L, LUA_GLOBALSINDEX, libname, size) != NULL)
+        luaL_error(L, "name conflict for module " LUA_QS, libname);
+      lua_pushvalue(L, -1);
+      lua_setfield(L, -3, libname);  /* _LOADED[libname] = new table */
+    }
+    lua_remove(L, -2);  /* remove _LOADED table */
+    lua_insert(L, -(nup+1));  /* move library table to below upvalues */
+  }
+  for (; l->name; l++) {
+    int i;
+    for (i=0; i<nup; i++)  /* copy upvalues to the top */
+      lua_pushvalue(L, -nup);
+    lua_pushcclosure(L, l->func, nup);
+    lua_setfield(L, -(nup+2), l->name);
+  }
+  lua_pop(L, nup);  /* remove upvalues */
+}
+
+
+
+/*
+** {======================================================
+** getn-setn: size for arrays
+** =======================================================
+*/
+
+#if defined(LUA_COMPAT_GETN)
+
+static int checkint (lua_State *L, int topop) {
+  int n = (lua_type(L, -1) == LUA_TNUMBER) ? lua_tointeger(L, -1) : -1;
+  lua_pop(L, topop);
+  return n;
+}
+
+
+static void getsizes (lua_State *L) {
+  lua_getfield(L, LUA_REGISTRYINDEX, "LUA_SIZES");
+  if (lua_isnil(L, -1)) {  /* no `size' table? */
+    lua_pop(L, 1);  /* remove nil */
+    lua_newtable(L);  /* create it */
+    lua_pushvalue(L, -1);  /* `size' will be its own metatable */
+    lua_setmetatable(L, -2);
+    lua_pushliteral(L, "kv");
+    lua_setfield(L, -2, "__mode");  /* metatable(N).__mode = "kv" */
+    lua_pushvalue(L, -1);
+    lua_setfield(L, LUA_REGISTRYINDEX, "LUA_SIZES");  /* store in register */
+  }
+}
+
+
+LUALIB_API void luaL_setn (lua_State *L, int t, int n) {
+  t = abs_index(L, t);
+  lua_pushliteral(L, "n");
+  lua_rawget(L, t);
+  if (checkint(L, 1) >= 0) {  /* is there a numeric field `n'? */
+    lua_pushliteral(L, "n");  /* use it */
+    lua_pushinteger(L, n);
+    lua_rawset(L, t);
+  }
+  else {  /* use `sizes' */
+    getsizes(L);
+    lua_pushvalue(L, t);
+    lua_pushinteger(L, n);
+    lua_rawset(L, -3);  /* sizes[t] = n */
+    lua_pop(L, 1);  /* remove `sizes' */
+  }
+}
+
+
+LUALIB_API int luaL_getn (lua_State *L, int t) {
+  int n;
+  t = abs_index(L, t);
+  lua_pushliteral(L, "n");  /* try t.n */
+  lua_rawget(L, t);
+  if ((n = checkint(L, 1)) >= 0) return n;
+  getsizes(L);  /* else try sizes[t] */
+  lua_pushvalue(L, t);
+  lua_rawget(L, -2);
+  if ((n = checkint(L, 2)) >= 0) return n;
+  return (int)lua_objlen(L, t);
+}
+
+#endif
+
+/* }====================================================== */
+
+
+
+LUALIB_API const char *luaL_gsub (lua_State *L, const char *s, const char *p,
+                                                               const char *r) {
+  const char *wild;
+  size_t l = strlen(p);
+  luaL_Buffer b;
+  luaL_buffinit(L, &b);
+  while ((wild = strstr(s, p)) != NULL) {
+    luaL_addlstring(&b, s, wild - s);  /* push prefix */
+    luaL_addstring(&b, r);  /* push replacement in place of pattern */
+    s = wild + l;  /* continue after `p' */
+  }
+  luaL_addstring(&b, s);  /* push last suffix */
+  luaL_pushresult(&b);
+  return lua_tostring(L, -1);
+}
+
+
+LUALIB_API const char *luaL_findtable (lua_State *L, int idx,
+                                       const char *fname, int szhint) {
+  const char *e;
+  lua_pushvalue(L, idx);
+  do {
+    e = strchr(fname, '.');
+    if (e == NULL) e = fname + strlen(fname);
+    lua_pushlstring(L, fname, e - fname);
+    lua_rawget(L, -2);
+    if (lua_isnil(L, -1)) {  /* no such field? */
+      lua_pop(L, 1);  /* remove this nil */
+      lua_createtable(L, 0, (*e == '.' ? 1 : szhint)); /* new table for field */
+      lua_pushlstring(L, fname, e - fname);
+      lua_pushvalue(L, -2);
+      lua_settable(L, -4);  /* set new table into field */
+    }
+    else if (!lua_istable(L, -1)) {  /* field has a non-table value? */
+      lua_pop(L, 2);  /* remove table and value */
+      return fname;  /* return problematic part of the name */
+    }
+    lua_remove(L, -2);  /* remove previous table */
+    fname = e + 1;
+  } while (*e == '.');
+  return NULL;
+}
+
+
+
+/*
+** {======================================================
+** Generic Buffer manipulation
+** =======================================================
+*/
+
+
+#define bufflen(B)	((B)->p - (B)->buffer)
+#define bufffree(B)	((size_t)(LUAL_BUFFERSIZE - bufflen(B)))
+
+#define LIMIT	(LUA_MINSTACK/2)
+
+
+static int emptybuffer (luaL_Buffer *B) {
+  size_t l = bufflen(B);
+  if (l == 0) return 0;  /* put nothing on stack */
+  else {
+    lua_pushlstring(B->L, B->buffer, l);
+    B->p = B->buffer;
+    B->lvl++;
+    return 1;
+  }
+}
+
+
+static void adjuststack (luaL_Buffer *B) {
+  if (B->lvl > 1) {
+    lua_State *L = B->L;
+    int toget = 1;  /* number of levels to concat */
+    size_t toplen = lua_strlen(L, -1);
+    do {
+      size_t l = lua_strlen(L, -(toget+1));
+      if (B->lvl - toget + 1 >= LIMIT || toplen > l) {
+        toplen += l;
+        toget++;
+      }
+      else break;
+    } while (toget < B->lvl);
+    lua_concat(L, toget);
+    B->lvl = B->lvl - toget + 1;
+  }
+}
+
+
+LUALIB_API char *luaL_prepbuffer (luaL_Buffer *B) {
+  if (emptybuffer(B))
+    adjuststack(B);
+  return B->buffer;
+}
+
+
+LUALIB_API void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l) {
+  while (l--)
+    luaL_addchar(B, *s++);
+}
+
+
+LUALIB_API void luaL_addstring (luaL_Buffer *B, const char *s) {
+  luaL_addlstring(B, s, strlen(s));
+}
+
+
+LUALIB_API void luaL_pushresult (luaL_Buffer *B) {
+  emptybuffer(B);
+  lua_concat(B->L, B->lvl);
+  B->lvl = 1;
+}
+
+
+LUALIB_API void luaL_addvalue (luaL_Buffer *B) {
+  lua_State *L = B->L;
+  size_t vl;
+  const char *s = lua_tolstring(L, -1, &vl);
+  if (vl <= bufffree(B)) {  /* fit into buffer? */
+    memcpy(B->p, s, vl);  /* put it there */
+    B->p += vl;
+    lua_pop(L, 1);  /* remove from stack */
+  }
+  else {
+    if (emptybuffer(B))
+      lua_insert(L, -2);  /* put buffer before new value */
+    B->lvl++;  /* add new value into B stack */
+    adjuststack(B);
+  }
+}
+
+
+LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) {
+  B->L = L;
+  B->p = B->buffer;
+  B->lvl = 0;
+}
+
+/* }====================================================== */
+
+
+LUALIB_API int luaL_ref (lua_State *L, int t) {
+  int ref;
+  t = abs_index(L, t);
+  if (lua_isnil(L, -1)) {
+    lua_pop(L, 1);  /* remove from stack */
+    return LUA_REFNIL;  /* `nil' has a unique fixed reference */
+  }
+  lua_rawgeti(L, t, FREELIST_REF);  /* get first free element */
+  ref = (int)lua_tointeger(L, -1);  /* ref = t[FREELIST_REF] */
+  lua_pop(L, 1);  /* remove it from stack */
+  if (ref != 0) {  /* any free element? */
+    lua_rawgeti(L, t, ref);  /* remove it from list */
+    lua_rawseti(L, t, FREELIST_REF);  /* (t[FREELIST_REF] = t[ref]) */
+  }
+  else {  /* no free elements */
+    ref = (int)lua_objlen(L, t);
+    ref++;  /* create new reference */
+  }
+  lua_rawseti(L, t, ref);
+  return ref;
+}
+
+
+LUALIB_API void luaL_unref (lua_State *L, int t, int ref) {
+  if (ref >= 0) {
+    t = abs_index(L, t);
+    lua_rawgeti(L, t, FREELIST_REF);
+    lua_rawseti(L, t, ref);  /* t[ref] = t[FREELIST_REF] */
+    lua_pushinteger(L, ref);
+    lua_rawseti(L, t, FREELIST_REF);  /* t[FREELIST_REF] = ref */
+  }
+}
+
+
+
+/*
+** {======================================================
+** Load functions
+** =======================================================
+*/
+
+typedef struct LoadF {
+  int extraline;
+  FILE *f;
+  char buff[LUAL_BUFFERSIZE];
+} LoadF;
+
+
+static const char *getF (lua_State *L, void *ud, size_t *size) {
+  LoadF *lf = (LoadF *)ud;
+  (void)L;
+  if (lf->extraline) {
+    lf->extraline = 0;
+    *size = 1;
+    return "\n";
+  }
+  if (feof(lf->f)) return NULL;
+  *size = fread(lf->buff, 1, sizeof(lf->buff), lf->f);
+  return (*size > 0) ? lf->buff : NULL;
+}
+
+
+static int errfile (lua_State *L, const char *what, int fnameindex) {
+  const char *serr = strerror(errno);
+  const char *filename = lua_tostring(L, fnameindex) + 1;
+  lua_pushfstring(L, "cannot %s %s: %s", what, filename, serr);
+  lua_remove(L, fnameindex);
+  return LUA_ERRFILE;
+}
+
+
+LUALIB_API int luaL_loadfile (lua_State *L, const char *filename) {
+  LoadF lf;
+  int status, readstatus;
+  int c;
+  int fnameindex = lua_gettop(L) + 1;  /* index of filename on the stack */
+  lf.extraline = 0;
+  if (filename == NULL) {
+    lua_pushliteral(L, "=stdin");
+    lf.f = stdin;
+  }
+  else {
+    lua_pushfstring(L, "@%s", filename);
+    lf.f = fopen(filename, "r");
+    if (lf.f == NULL) return errfile(L, "open", fnameindex);
+  }
+#if 0
+  c = getc(lf.f);
+  if (c == '#') {  /* Unix exec. file? */
+    lf.extraline = 1;
+    while ((c = getc(lf.f)) != EOF && c != '\n') ;  /* skip first line */
+    if (c == '\n') c = getc(lf.f);
+  }
+  if (c == LUA_SIGNATURE[0] && filename) {  /* binary file? */
+    lf.f = freopen(filename, "rb", lf.f);  /* reopen in binary mode */
+    if (lf.f == NULL) return errfile(L, "reopen", fnameindex);
+    /* skip eventual `#!...' */
+   while ((c = getc(lf.f)) != EOF && c != LUA_SIGNATURE[0]) ;
+    lf.extraline = 0;
+  }
+  ungetc(c, lf.f);
+#endif
+  status = lua_load(L, getF, &lf, lua_tostring(L, -1));
+  readstatus = ferror(lf.f);
+  if (filename) fclose(lf.f);  /* close file (even in case of errors) */
+  if (readstatus) {
+    lua_settop(L, fnameindex);  /* ignore results from `lua_load' */
+    return errfile(L, "read", fnameindex);
+  }
+  lua_remove(L, fnameindex);
+  return status;
+}
+
+
+typedef struct LoadS {
+  const char *s;
+  size_t size;
+} LoadS;
+
+
+static const char *getS (lua_State *L, void *ud, size_t *size) {
+  LoadS *ls = (LoadS *)ud;
+  (void)L;
+  if (ls->size == 0) return NULL;
+  *size = ls->size;
+  ls->size = 0;
+  return ls->s;
+}
+
+
+LUALIB_API int luaL_loadbuffer (lua_State *L, const char *buff, size_t size,
+                                const char *name) {
+  LoadS ls;
+  ls.s = buff;
+  ls.size = size;
+  return lua_load(L, getS, &ls, name);
+}
+
+
+LUALIB_API int (luaL_loadstring) (lua_State *L, const char *s) {
+  return luaL_loadbuffer(L, s, strlen(s), s);
+}
+
+
+
+/* }====================================================== */
+
+
+static void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize) {
+  (void)ud;
+  (void)osize;
+  if (nsize == 0) {
+    free(ptr);
+    return NULL;
+  }
+  else
+    return realloc(ptr, nsize);
+}
+
+
+static int panic (lua_State *L) {
+  (void)L;  /* to avoid warnings */
+  fprintf(stderr, "PANIC: unprotected error in call to Lua API (%s)\n",
+                   lua_tostring(L, -1));
+  return 0;
+}
+
+
+LUALIB_API lua_State *luaL_newstate (void) {
+  lua_State *L = lua_newstate(l_alloc, NULL);
+  if (L) lua_atpanic(L, &panic);
+  return L;
+}
+
diff --git a/com32/lua/src/lauxlib.h b/com32/lua/src/lauxlib.h
new file mode 100644
index 00000000..34258235
--- /dev/null
+++ b/com32/lua/src/lauxlib.h
@@ -0,0 +1,174 @@
+/*
+** $Id: lauxlib.h,v 1.88.1.1 2007/12/27 13:02:25 roberto Exp $
+** Auxiliary functions for building Lua libraries
+** See Copyright Notice in lua.h
+*/
+
+
+#ifndef lauxlib_h
+#define lauxlib_h
+
+
+#include <stddef.h>
+#include <stdio.h>
+
+#include "lua.h"
+
+
+#if defined(LUA_COMPAT_GETN)
+LUALIB_API int (luaL_getn) (lua_State *L, int t);
+LUALIB_API void (luaL_setn) (lua_State *L, int t, int n);
+#else
+#define luaL_getn(L,i)          ((int)lua_objlen(L, i))
+#define luaL_setn(L,i,j)        ((void)0)  /* no op! */
+#endif
+
+#if defined(LUA_COMPAT_OPENLIB)
+#define luaI_openlib	luaL_openlib
+#endif
+
+
+/* extra error code for `luaL_load' */
+#define LUA_ERRFILE     (LUA_ERRERR+1)
+
+
+typedef struct luaL_Reg {
+  const char *name;
+  lua_CFunction func;
+} luaL_Reg;
+
+
+
+LUALIB_API void (luaI_openlib) (lua_State *L, const char *libname,
+                                const luaL_Reg *l, int nup);
+LUALIB_API void (luaL_register) (lua_State *L, const char *libname,
+                                const luaL_Reg *l);
+LUALIB_API int (luaL_getmetafield) (lua_State *L, int obj, const char *e);
+LUALIB_API int (luaL_callmeta) (lua_State *L, int obj, const char *e);
+LUALIB_API int (luaL_typerror) (lua_State *L, int narg, const char *tname);
+LUALIB_API int (luaL_argerror) (lua_State *L, int numarg, const char *extramsg);
+LUALIB_API const char *(luaL_checklstring) (lua_State *L, int numArg,
+                                                          size_t *l);
+LUALIB_API const char *(luaL_optlstring) (lua_State *L, int numArg,
+                                          const char *def, size_t *l);
+LUALIB_API lua_Number (luaL_checknumber) (lua_State *L, int numArg);
+LUALIB_API lua_Number (luaL_optnumber) (lua_State *L, int nArg, lua_Number def);
+
+LUALIB_API lua_Integer (luaL_checkinteger) (lua_State *L, int numArg);
+LUALIB_API lua_Integer (luaL_optinteger) (lua_State *L, int nArg,
+                                          lua_Integer def);
+
+LUALIB_API void (luaL_checkstack) (lua_State *L, int sz, const char *msg);
+LUALIB_API void (luaL_checktype) (lua_State *L, int narg, int t);
+LUALIB_API void (luaL_checkany) (lua_State *L, int narg);
+
+LUALIB_API int   (luaL_newmetatable) (lua_State *L, const char *tname);
+LUALIB_API void *(luaL_checkudata) (lua_State *L, int ud, const char *tname);
+
+LUALIB_API void (luaL_where) (lua_State *L, int lvl);
+LUALIB_API int (luaL_error) (lua_State *L, const char *fmt, ...);
+
+LUALIB_API int (luaL_checkoption) (lua_State *L, int narg, const char *def,
+                                   const char *const lst[]);
+
+LUALIB_API int (luaL_ref) (lua_State *L, int t);
+LUALIB_API void (luaL_unref) (lua_State *L, int t, int ref);
+
+LUALIB_API int (luaL_loadfile) (lua_State *L, const char *filename);
+LUALIB_API int (luaL_loadbuffer) (lua_State *L, const char *buff, size_t sz,
+                                  const char *name);
+LUALIB_API int (luaL_loadstring) (lua_State *L, const char *s);
+
+LUALIB_API lua_State *(luaL_newstate) (void);
+
+
+LUALIB_API const char *(luaL_gsub) (lua_State *L, const char *s, const char *p,
+                                                  const char *r);
+
+LUALIB_API const char *(luaL_findtable) (lua_State *L, int idx,
+                                         const char *fname, int szhint);
+
+
+
+
+/*
+** ===============================================================
+** some useful macros
+** ===============================================================
+*/
+
+#define luaL_argcheck(L, cond,numarg,extramsg)	\
+		((void)((cond) || luaL_argerror(L, (numarg), (extramsg))))
+#define luaL_checkstring(L,n)	(luaL_checklstring(L, (n), NULL))
+#define luaL_optstring(L,n,d)	(luaL_optlstring(L, (n), (d), NULL))
+#define luaL_checkint(L,n)	((int)luaL_checkinteger(L, (n)))
+#define luaL_optint(L,n,d)	((int)luaL_optinteger(L, (n), (d)))
+#define luaL_checklong(L,n)	((long)luaL_checkinteger(L, (n)))
+#define luaL_optlong(L,n,d)	((long)luaL_optinteger(L, (n), (d)))
+
+#define luaL_typename(L,i)	lua_typename(L, lua_type(L,(i)))
+
+#define luaL_dofile(L, fn) \
+	(luaL_loadfile(L, fn) || lua_pcall(L, 0, LUA_MULTRET, 0))
+
+#define luaL_dostring(L, s) \
+	(luaL_loadstring(L, s) || lua_pcall(L, 0, LUA_MULTRET, 0))
+
+#define luaL_getmetatable(L,n)	(lua_getfield(L, LUA_REGISTRYINDEX, (n)))
+
+#define luaL_opt(L,f,n,d)	(lua_isnoneornil(L,(n)) ? (d) : f(L,(n)))
+
+/*
+** {======================================================
+** Generic Buffer manipulation
+** =======================================================
+*/
+
+
+
+typedef struct luaL_Buffer {
+  char *p;			/* current position in buffer */
+  int lvl;  /* number of strings in the stack (level) */
+  lua_State *L;
+  char buffer[LUAL_BUFFERSIZE];
+} luaL_Buffer;
+
+#define luaL_addchar(B,c) \
+  ((void)((B)->p < ((B)->buffer+LUAL_BUFFERSIZE) || luaL_prepbuffer(B)), \
+   (*(B)->p++ = (char)(c)))
+
+/* compatibility only */
+#define luaL_putchar(B,c)	luaL_addchar(B,c)
+
+#define luaL_addsize(B,n)	((B)->p += (n))
+
+LUALIB_API void (luaL_buffinit) (lua_State *L, luaL_Buffer *B);
+LUALIB_API char *(luaL_prepbuffer) (luaL_Buffer *B);
+LUALIB_API void (luaL_addlstring) (luaL_Buffer *B, const char *s, size_t l);
+LUALIB_API void (luaL_addstring) (luaL_Buffer *B, const char *s);
+LUALIB_API void (luaL_addvalue) (luaL_Buffer *B);
+LUALIB_API void (luaL_pushresult) (luaL_Buffer *B);
+
+
+/* }====================================================== */
+
+
+/* compatibility with ref system */
+
+/* pre-defined references */
+#define LUA_NOREF       (-2)
+#define LUA_REFNIL      (-1)
+
+#define lua_ref(L,lock) ((lock) ? luaL_ref(L, LUA_REGISTRYINDEX) : \
+      (lua_pushstring(L, "unlocked references are obsolete"), lua_error(L), 0))
+
+#define lua_unref(L,ref)        luaL_unref(L, LUA_REGISTRYINDEX, (ref))
+
+#define lua_getref(L,ref)       lua_rawgeti(L, LUA_REGISTRYINDEX, (ref))
+
+
+#define luaL_reg	luaL_Reg
+
+#endif
+
+
diff --git a/com32/lua/src/lbaselib.c b/com32/lua/src/lbaselib.c
new file mode 100644
index 00000000..eb06bcef
--- /dev/null
+++ b/com32/lua/src/lbaselib.c
@@ -0,0 +1,651 @@
+/*
+** $Id: lbaselib.c,v 1.191.1.4 2008/01/20 13:53:22 roberto Exp $
+** Basic library
+** See Copyright Notice in lua.h
+*/
+
+
+
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define lbaselib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+
+
+/*
+** If your system does not support `stdout', you can just remove this function.
+** If you need, you can define your own `print' function, following this
+** model but changing `fputs' to put the strings at a proper place
+** (a console window or a log file, for instance).
+*/
+static int luaB_print (lua_State *L) {
+  int n = lua_gettop(L);  /* number of arguments */
+  int i;
+  lua_getglobal(L, "tostring");
+  for (i=1; i<=n; i++) {
+    const char *s;
+    lua_pushvalue(L, -1);  /* function to be called */
+    lua_pushvalue(L, i);   /* value to print */
+    lua_call(L, 1, 1);
+    s = lua_tostring(L, -1);  /* get result */
+    if (s == NULL)
+      return luaL_error(L, LUA_QL("tostring") " must return a string to "
+                           LUA_QL("print"));
+    if (i>1) fputs("\t", stdout);
+    fputs(s, stdout);
+    lua_pop(L, 1);  /* pop result */
+  }
+  fputs("\n", stdout);
+  return 0;
+}
+
+
+static int luaB_tonumber (lua_State *L) {
+  int base = luaL_optint(L, 2, 10);
+  if (base == 10) {  /* standard conversion */
+    luaL_checkany(L, 1);
+    if (lua_isnumber(L, 1)) {
+      lua_pushnumber(L, lua_tonumber(L, 1));
+      return 1;
+    }
+  }
+  else {
+    const char *s1 = luaL_checkstring(L, 1);
+    char *s2;
+    unsigned long n;
+    luaL_argcheck(L, 2 <= base && base <= 36, 2, "base out of range");
+    n = strtoul(s1, &s2, base);
+    if (s1 != s2) {  /* at least one valid digit? */
+      while (isspace((unsigned char)(*s2))) s2++;  /* skip trailing spaces */
+      if (*s2 == '\0') {  /* no invalid trailing characters? */
+        lua_pushnumber(L, (lua_Number)n);
+        return 1;
+      }
+    }
+  }
+  lua_pushnil(L);  /* else not a number */
+  return 1;
+}
+
+
+static int luaB_error (lua_State *L) {
+  int level = luaL_optint(L, 2, 1);
+  lua_settop(L, 1);
+  if (lua_isstring(L, 1) && level > 0) {  /* add extra information? */
+    luaL_where(L, level);
+    lua_pushvalue(L, 1);
+    lua_concat(L, 2);
+  }
+  return lua_error(L);
+}
+
+
+static int luaB_getmetatable (lua_State *L) {
+  luaL_checkany(L, 1);
+  if (!lua_getmetatable(L, 1)) {
+    lua_pushnil(L);
+    return 1;  /* no metatable */
+  }
+  luaL_getmetafield(L, 1, "__metatable");
+  return 1;  /* returns either __metatable field (if present) or metatable */
+}
+
+
+static int luaB_setmetatable (lua_State *L) {
+  int t = lua_type(L, 2);
+  luaL_checktype(L, 1, LUA_TTABLE);
+  luaL_argcheck(L, t == LUA_TNIL || t == LUA_TTABLE, 2,
+                    "nil or table expected");
+  if (luaL_getmetafield(L, 1, "__metatable"))
+    luaL_error(L, "cannot change a protected metatable");
+  lua_settop(L, 2);
+  lua_setmetatable(L, 1);
+  return 1;
+}
+
+
+static void getfunc (lua_State *L, int opt) {
+  if (lua_isfunction(L, 1)) lua_pushvalue(L, 1);
+  else {
+    lua_Debug ar;
+    int level = opt ? luaL_optint(L, 1, 1) : luaL_checkint(L, 1);
+    luaL_argcheck(L, level >= 0, 1, "level must be non-negative");
+    if (lua_getstack(L, level, &ar) == 0)
+      luaL_argerror(L, 1, "invalid level");
+    lua_getinfo(L, "f", &ar);
+    if (lua_isnil(L, -1))
+      luaL_error(L, "no function environment for tail call at level %d",
+                    level);
+  }
+}
+
+
+static int luaB_getfenv (lua_State *L) {
+  getfunc(L, 1);
+  if (lua_iscfunction(L, -1))  /* is a C function? */
+    lua_pushvalue(L, LUA_GLOBALSINDEX);  /* return the thread's global env. */
+  else
+    lua_getfenv(L, -1);
+  return 1;
+}
+
+
+static int luaB_setfenv (lua_State *L) {
+  luaL_checktype(L, 2, LUA_TTABLE);
+  getfunc(L, 0);
+  lua_pushvalue(L, 2);
+  if (lua_isnumber(L, 1) && lua_tonumber(L, 1) == 0) {
+    /* change environment of current thread */
+    lua_pushthread(L);
+    lua_insert(L, -2);
+    lua_setfenv(L, -2);
+    return 0;
+  }
+  else if (lua_iscfunction(L, -2) || lua_setfenv(L, -2) == 0)
+    luaL_error(L,
+          LUA_QL("setfenv") " cannot change environment of given object");
+  return 1;
+}
+
+
+static int luaB_rawequal (lua_State *L) {
+  luaL_checkany(L, 1);
+  luaL_checkany(L, 2);
+  lua_pushboolean(L, lua_rawequal(L, 1, 2));
+  return 1;
+}
+
+
+static int luaB_rawget (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  luaL_checkany(L, 2);
+  lua_settop(L, 2);
+  lua_rawget(L, 1);
+  return 1;
+}
+
+static int luaB_rawset (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  luaL_checkany(L, 2);
+  luaL_checkany(L, 3);
+  lua_settop(L, 3);
+  lua_rawset(L, 1);
+  return 1;
+}
+
+
+static int luaB_gcinfo (lua_State *L) {
+  lua_pushinteger(L, lua_getgccount(L));
+  return 1;
+}
+
+
+static int luaB_collectgarbage (lua_State *L) {
+  static const char *const opts[] = {"stop", "restart", "collect",
+    "count", "step", "setpause", "setstepmul", NULL};
+  static const int optsnum[] = {LUA_GCSTOP, LUA_GCRESTART, LUA_GCCOLLECT,
+    LUA_GCCOUNT, LUA_GCSTEP, LUA_GCSETPAUSE, LUA_GCSETSTEPMUL};
+  int o = luaL_checkoption(L, 1, "collect", opts);
+  int ex = luaL_optint(L, 2, 0);
+  int res = lua_gc(L, optsnum[o], ex);
+  switch (optsnum[o]) {
+    case LUA_GCCOUNT: {
+      int b = lua_gc(L, LUA_GCCOUNTB, 0);
+      lua_pushnumber(L, res + ((lua_Number)b/1024));
+      return 1;
+    }
+    case LUA_GCSTEP: {
+      lua_pushboolean(L, res);
+      return 1;
+    }
+    default: {
+      lua_pushnumber(L, res);
+      return 1;
+    }
+  }
+}
+
+
+static int luaB_type (lua_State *L) {
+  luaL_checkany(L, 1);
+  lua_pushstring(L, luaL_typename(L, 1));
+  return 1;
+}
+
+
+static int luaB_next (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  lua_settop(L, 2);  /* create a 2nd argument if there isn't one */
+  if (lua_next(L, 1))
+    return 2;
+  else {
+    lua_pushnil(L);
+    return 1;
+  }
+}
+
+
+static int luaB_pairs (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  lua_pushvalue(L, lua_upvalueindex(1));  /* return generator, */
+  lua_pushvalue(L, 1);  /* state, */
+  lua_pushnil(L);  /* and initial value */
+  return 3;
+}
+
+
+static int ipairsaux (lua_State *L) {
+  int i = luaL_checkint(L, 2);
+  luaL_checktype(L, 1, LUA_TTABLE);
+  i++;  /* next value */
+  lua_pushinteger(L, i);
+  lua_rawgeti(L, 1, i);
+  return (lua_isnil(L, -1)) ? 0 : 2;
+}
+
+
+static int luaB_ipairs (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  lua_pushvalue(L, lua_upvalueindex(1));  /* return generator, */
+  lua_pushvalue(L, 1);  /* state, */
+  lua_pushinteger(L, 0);  /* and initial value */
+  return 3;
+}
+
+
+static int load_aux (lua_State *L, int status) {
+  if (status == 0)  /* OK? */
+    return 1;
+  else {
+    lua_pushnil(L);
+    lua_insert(L, -2);  /* put before error message */
+    return 2;  /* return nil plus error message */
+  }
+}
+
+
+static int luaB_loadstring (lua_State *L) {
+  size_t l;
+  const char *s = luaL_checklstring(L, 1, &l);
+  const char *chunkname = luaL_optstring(L, 2, s);
+  return load_aux(L, luaL_loadbuffer(L, s, l, chunkname));
+}
+
+
+static int luaB_loadfile (lua_State *L) {
+  const char *fname = luaL_optstring(L, 1, NULL);
+  return load_aux(L, luaL_loadfile(L, fname));
+}
+
+
+/*
+** Reader for generic `load' function: `lua_load' uses the
+** stack for internal stuff, so the reader cannot change the
+** stack top. Instead, it keeps its resulting string in a
+** reserved slot inside the stack.
+*/
+static const char *generic_reader (lua_State *L, void *ud, size_t *size) {
+  (void)ud;  /* to avoid warnings */
+  luaL_checkstack(L, 2, "too many nested functions");
+  lua_pushvalue(L, 1);  /* get function */
+  lua_call(L, 0, 1);  /* call it */
+  if (lua_isnil(L, -1)) {
+    *size = 0;
+    return NULL;
+  }
+  else if (lua_isstring(L, -1)) {
+    lua_replace(L, 3);  /* save string in a reserved stack slot */
+    return lua_tolstring(L, 3, size);
+  }
+  else luaL_error(L, "reader function must return a string");
+  return NULL;  /* to avoid warnings */
+}
+
+
+static int luaB_load (lua_State *L) {
+  int status;
+  const char *cname = luaL_optstring(L, 2, "=(load)");
+  luaL_checktype(L, 1, LUA_TFUNCTION);
+  lua_settop(L, 3);  /* function, eventual name, plus one reserved slot */
+  status = lua_load(L, generic_reader, NULL, cname);
+  return load_aux(L, status);
+}
+
+
+static int luaB_dofile (lua_State *L) {
+  const char *fname = luaL_optstring(L, 1, NULL);
+  int n = lua_gettop(L);
+  if (luaL_loadfile(L, fname) != 0) lua_error(L);
+  lua_call(L, 0, LUA_MULTRET);
+  return lua_gettop(L) - n;
+}
+
+
+static int luaB_assert (lua_State *L) {
+  luaL_checkany(L, 1);
+  if (!lua_toboolean(L, 1))
+    return luaL_error(L, "%s", luaL_optstring(L, 2, "assertion failed!"));
+  return lua_gettop(L);
+}
+
+
+static int luaB_unpack (lua_State *L) {
+  int i, e, n;
+  luaL_checktype(L, 1, LUA_TTABLE);
+  i = luaL_optint(L, 2, 1);
+  e = luaL_opt(L, luaL_checkint, 3, luaL_getn(L, 1));
+  n = e - i + 1;  /* number of elements */
+  if (n <= 0) return 0;  /* empty range */
+  luaL_checkstack(L, n, "table too big to unpack");
+  for (; i<=e; i++)  /* push arg[i...e] */
+    lua_rawgeti(L, 1, i);
+  return n;
+}
+
+
+static int luaB_select (lua_State *L) {
+  int n = lua_gettop(L);
+  if (lua_type(L, 1) == LUA_TSTRING && *lua_tostring(L, 1) == '#') {
+    lua_pushinteger(L, n-1);
+    return 1;
+  }
+  else {
+    int i = luaL_checkint(L, 1);
+    if (i < 0) i = n + i;
+    else if (i > n) i = n;
+    luaL_argcheck(L, 1 <= i, 1, "index out of range");
+    return n - i;
+  }
+}
+
+
+static int luaB_pcall (lua_State *L) {
+  int status;
+  luaL_checkany(L, 1);
+  status = lua_pcall(L, lua_gettop(L) - 1, LUA_MULTRET, 0);
+  lua_pushboolean(L, (status == 0));
+  lua_insert(L, 1);
+  return lua_gettop(L);  /* return status + all results */
+}
+
+
+static int luaB_xpcall (lua_State *L) {
+  int status;
+  luaL_checkany(L, 2);
+  lua_settop(L, 2);
+  lua_insert(L, 1);  /* put error function under function to be called */
+  status = lua_pcall(L, 0, LUA_MULTRET, 1);
+  lua_pushboolean(L, (status == 0));
+  lua_replace(L, 1);
+  return lua_gettop(L);  /* return status + all results */
+}
+
+
+static int luaB_tostring (lua_State *L) {
+  luaL_checkany(L, 1);
+  if (luaL_callmeta(L, 1, "__tostring"))  /* is there a metafield? */
+    return 1;  /* use its value */
+  switch (lua_type(L, 1)) {
+    case LUA_TNUMBER:
+      lua_pushstring(L, lua_tostring(L, 1));
+      break;
+    case LUA_TSTRING:
+      lua_pushvalue(L, 1);
+      break;
+    case LUA_TBOOLEAN:
+      lua_pushstring(L, (lua_toboolean(L, 1) ? "true" : "false"));
+      break;
+    case LUA_TNIL:
+      lua_pushliteral(L, "nil");
+      break;
+    default:
+      lua_pushfstring(L, "%s: %p", luaL_typename(L, 1), lua_topointer(L, 1));
+      break;
+  }
+  return 1;
+}
+
+
+static int luaB_newproxy (lua_State *L) {
+  lua_settop(L, 1);
+  lua_newuserdata(L, 0);  /* create proxy */
+  if (lua_toboolean(L, 1) == 0)
+    return 1;  /* no metatable */
+  else if (lua_isboolean(L, 1)) {
+    lua_newtable(L);  /* create a new metatable `m' ... */
+    lua_pushvalue(L, -1);  /* ... and mark `m' as a valid metatable */
+    lua_pushboolean(L, 1);
+    lua_rawset(L, lua_upvalueindex(1));  /* weaktable[m] = true */
+  }
+  else {
+    int validproxy = 0;  /* to check if weaktable[metatable(u)] == true */
+    if (lua_getmetatable(L, 1)) {
+      lua_rawget(L, lua_upvalueindex(1));
+      validproxy = lua_toboolean(L, -1);
+      lua_pop(L, 1);  /* remove value */
+    }
+    luaL_argcheck(L, validproxy, 1, "boolean or proxy expected");
+    lua_getmetatable(L, 1);  /* metatable is valid; get it */
+  }
+  lua_setmetatable(L, 2);
+  return 1;
+}
+
+
+static const luaL_Reg base_funcs[] = {
+  {"assert", luaB_assert},
+  {"collectgarbage", luaB_collectgarbage},
+  {"dofile", luaB_dofile},
+  {"error", luaB_error},
+  {"gcinfo", luaB_gcinfo},
+  {"getfenv", luaB_getfenv},
+  {"getmetatable", luaB_getmetatable},
+  {"loadfile", luaB_loadfile},
+  {"load", luaB_load},
+  {"loadstring", luaB_loadstring},
+  {"next", luaB_next},
+  {"pcall", luaB_pcall},
+  {"print", luaB_print},
+  {"rawequal", luaB_rawequal},
+  {"rawget", luaB_rawget},
+  {"rawset", luaB_rawset},
+  {"select", luaB_select},
+  {"setfenv", luaB_setfenv},
+  {"setmetatable", luaB_setmetatable},
+  {"tonumber", luaB_tonumber},
+  {"tostring", luaB_tostring},
+  {"type", luaB_type},
+  {"unpack", luaB_unpack},
+  {"xpcall", luaB_xpcall},
+  {NULL, NULL}
+};
+
+
+/*
+** {======================================================
+** Coroutine library
+** =======================================================
+*/
+
+#define CO_RUN	0	/* running */
+#define CO_SUS	1	/* suspended */
+#define CO_NOR	2	/* 'normal' (it resumed another coroutine) */
+#define CO_DEAD	3
+
+static const char *const statnames[] =
+    {"running", "suspended", "normal", "dead"};
+
+static int costatus (lua_State *L, lua_State *co) {
+  if (L == co) return CO_RUN;
+  switch (lua_status(co)) {
+    case LUA_YIELD:
+      return CO_SUS;
+    case 0: {
+      lua_Debug ar;
+      if (lua_getstack(co, 0, &ar) > 0)  /* does it have frames? */
+        return CO_NOR;  /* it is running */
+      else if (lua_gettop(co) == 0)
+          return CO_DEAD;
+      else
+        return CO_SUS;  /* initial state */
+    }
+    default:  /* some error occured */
+      return CO_DEAD;
+  }
+}
+
+
+static int luaB_costatus (lua_State *L) {
+  lua_State *co = lua_tothread(L, 1);
+  luaL_argcheck(L, co, 1, "coroutine expected");
+  lua_pushstring(L, statnames[costatus(L, co)]);
+  return 1;
+}
+
+
+static int auxresume (lua_State *L, lua_State *co, int narg) {
+  int status = costatus(L, co);
+  if (!lua_checkstack(co, narg))
+    luaL_error(L, "too many arguments to resume");
+  if (status != CO_SUS) {
+    lua_pushfstring(L, "cannot resume %s coroutine", statnames[status]);
+    return -1;  /* error flag */
+  }
+  lua_xmove(L, co, narg);
+  lua_setlevel(L, co);
+  status = lua_resume(co, narg);
+  if (status == 0 || status == LUA_YIELD) {
+    int nres = lua_gettop(co);
+    if (!lua_checkstack(L, nres))
+      luaL_error(L, "too many results to resume");
+    lua_xmove(co, L, nres);  /* move yielded values */
+    return nres;
+  }
+  else {
+    lua_xmove(co, L, 1);  /* move error message */
+    return -1;  /* error flag */
+  }
+}
+
+
+static int luaB_coresume (lua_State *L) {
+  lua_State *co = lua_tothread(L, 1);
+  int r;
+  luaL_argcheck(L, co, 1, "coroutine expected");
+  r = auxresume(L, co, lua_gettop(L) - 1);
+  if (r < 0) {
+    lua_pushboolean(L, 0);
+    lua_insert(L, -2);
+    return 2;  /* return false + error message */
+  }
+  else {
+    lua_pushboolean(L, 1);
+    lua_insert(L, -(r + 1));
+    return r + 1;  /* return true + `resume' returns */
+  }
+}
+
+
+static int luaB_auxwrap (lua_State *L) {
+  lua_State *co = lua_tothread(L, lua_upvalueindex(1));
+  int r = auxresume(L, co, lua_gettop(L));
+  if (r < 0) {
+    if (lua_isstring(L, -1)) {  /* error object is a string? */
+      luaL_where(L, 1);  /* add extra info */
+      lua_insert(L, -2);
+      lua_concat(L, 2);
+    }
+    lua_error(L);  /* propagate error */
+  }
+  return r;
+}
+
+
+static int luaB_cocreate (lua_State *L) {
+  lua_State *NL = lua_newthread(L);
+  luaL_argcheck(L, lua_isfunction(L, 1) && !lua_iscfunction(L, 1), 1,
+    "Lua function expected");
+  lua_pushvalue(L, 1);  /* move function to top */
+  lua_xmove(L, NL, 1);  /* move function from L to NL */
+  return 1;
+}
+
+
+static int luaB_cowrap (lua_State *L) {
+  luaB_cocreate(L);
+  lua_pushcclosure(L, luaB_auxwrap, 1);
+  return 1;
+}
+
+
+static int luaB_yield (lua_State *L) {
+  return lua_yield(L, lua_gettop(L));
+}
+
+
+static int luaB_corunning (lua_State *L) {
+  if (lua_pushthread(L))
+    lua_pushnil(L);  /* main thread is not a coroutine */
+  return 1;
+}
+
+
+static const luaL_Reg co_funcs[] = {
+  {"create", luaB_cocreate},
+  {"resume", luaB_coresume},
+  {"running", luaB_corunning},
+  {"status", luaB_costatus},
+  {"wrap", luaB_cowrap},
+  {"yield", luaB_yield},
+  {NULL, NULL}
+};
+
+/* }====================================================== */
+
+
+static void auxopen (lua_State *L, const char *name,
+                     lua_CFunction f, lua_CFunction u) {
+  lua_pushcfunction(L, u);
+  lua_pushcclosure(L, f, 1);
+  lua_setfield(L, -2, name);
+}
+
+
+static void base_open (lua_State *L) {
+  /* set global _G */
+  lua_pushvalue(L, LUA_GLOBALSINDEX);
+  lua_setglobal(L, "_G");
+  /* open lib into global table */
+  luaL_register(L, "_G", base_funcs);
+  lua_pushliteral(L, LUA_VERSION);
+  lua_setglobal(L, "_VERSION");  /* set global _VERSION */
+  /* `ipairs' and `pairs' need auxliliary functions as upvalues */
+  auxopen(L, "ipairs", luaB_ipairs, ipairsaux);
+  auxopen(L, "pairs", luaB_pairs, luaB_next);
+  /* `newproxy' needs a weaktable as upvalue */
+  lua_createtable(L, 0, 1);  /* new table `w' */
+  lua_pushvalue(L, -1);  /* `w' will be its own metatable */
+  lua_setmetatable(L, -2);
+  lua_pushliteral(L, "kv");
+  lua_setfield(L, -2, "__mode");  /* metatable(w).__mode = "kv" */
+  lua_pushcclosure(L, luaB_newproxy, 1);
+  lua_setglobal(L, "newproxy");  /* set global `newproxy' */
+}
+
+
+LUALIB_API int luaopen_base (lua_State *L) {
+  base_open(L);
+  luaL_register(L, LUA_COLIBNAME, co_funcs);
+  return 2;
+}
+
diff --git a/com32/lua/src/lcode.c b/com32/lua/src/lcode.c
new file mode 100644
index 00000000..cff626b7
--- /dev/null
+++ b/com32/lua/src/lcode.c
@@ -0,0 +1,839 @@
+/*
+** $Id: lcode.c,v 2.25.1.3 2007/12/28 15:32:23 roberto Exp $
+** Code generator for Lua
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stdlib.h>
+
+#define lcode_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "lcode.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lgc.h"
+#include "llex.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lparser.h"
+#include "ltable.h"
+
+
+#define hasjumps(e)	((e)->t != (e)->f)
+
+
+static int isnumeral(expdesc *e) {
+  return (e->k == VKNUM && e->t == NO_JUMP && e->f == NO_JUMP);
+}
+
+
+void luaK_nil (FuncState *fs, int from, int n) {
+  Instruction *previous;
+  if (fs->pc > fs->lasttarget) {  /* no jumps to current position? */
+    if (fs->pc == 0) {  /* function start? */
+      if (from >= fs->nactvar)
+        return;  /* positions are already clean */
+    }
+    else {
+      previous = &fs->f->code[fs->pc-1];
+      if (GET_OPCODE(*previous) == OP_LOADNIL) {
+        int pfrom = GETARG_A(*previous);
+        int pto = GETARG_B(*previous);
+        if (pfrom <= from && from <= pto+1) {  /* can connect both? */
+          if (from+n-1 > pto)
+            SETARG_B(*previous, from+n-1);
+          return;
+        }
+      }
+    }
+  }
+  luaK_codeABC(fs, OP_LOADNIL, from, from+n-1, 0);  /* else no optimization */
+}
+
+
+int luaK_jump (FuncState *fs) {
+  int jpc = fs->jpc;  /* save list of jumps to here */
+  int j;
+  fs->jpc = NO_JUMP;
+  j = luaK_codeAsBx(fs, OP_JMP, 0, NO_JUMP);
+  luaK_concat(fs, &j, jpc);  /* keep them on hold */
+  return j;
+}
+
+
+void luaK_ret (FuncState *fs, int first, int nret) {
+  luaK_codeABC(fs, OP_RETURN, first, nret+1, 0);
+}
+
+
+static int condjump (FuncState *fs, OpCode op, int A, int B, int C) {
+  luaK_codeABC(fs, op, A, B, C);
+  return luaK_jump(fs);
+}
+
+
+static void fixjump (FuncState *fs, int pc, int dest) {
+  Instruction *jmp = &fs->f->code[pc];
+  int offset = dest-(pc+1);
+  lua_assert(dest != NO_JUMP);
+  if (abs(offset) > MAXARG_sBx)
+    luaX_syntaxerror(fs->ls, "control structure too long");
+  SETARG_sBx(*jmp, offset);
+}
+
+
+/*
+** returns current `pc' and marks it as a jump target (to avoid wrong
+** optimizations with consecutive instructions not in the same basic block).
+*/
+int luaK_getlabel (FuncState *fs) {
+  fs->lasttarget = fs->pc;
+  return fs->pc;
+}
+
+
+static int getjump (FuncState *fs, int pc) {
+  int offset = GETARG_sBx(fs->f->code[pc]);
+  if (offset == NO_JUMP)  /* point to itself represents end of list */
+    return NO_JUMP;  /* end of list */
+  else
+    return (pc+1)+offset;  /* turn offset into absolute position */
+}
+
+
+static Instruction *getjumpcontrol (FuncState *fs, int pc) {
+  Instruction *pi = &fs->f->code[pc];
+  if (pc >= 1 && testTMode(GET_OPCODE(*(pi-1))))
+    return pi-1;
+  else
+    return pi;
+}
+
+
+/*
+** check whether list has any jump that do not produce a value
+** (or produce an inverted value)
+*/
+static int need_value (FuncState *fs, int list) {
+  for (; list != NO_JUMP; list = getjump(fs, list)) {
+    Instruction i = *getjumpcontrol(fs, list);
+    if (GET_OPCODE(i) != OP_TESTSET) return 1;
+  }
+  return 0;  /* not found */
+}
+
+
+static int patchtestreg (FuncState *fs, int node, int reg) {
+  Instruction *i = getjumpcontrol(fs, node);
+  if (GET_OPCODE(*i) != OP_TESTSET)
+    return 0;  /* cannot patch other instructions */
+  if (reg != NO_REG && reg != GETARG_B(*i))
+    SETARG_A(*i, reg);
+  else  /* no register to put value or register already has the value */
+    *i = CREATE_ABC(OP_TEST, GETARG_B(*i), 0, GETARG_C(*i));
+
+  return 1;
+}
+
+
+static void removevalues (FuncState *fs, int list) {
+  for (; list != NO_JUMP; list = getjump(fs, list))
+      patchtestreg(fs, list, NO_REG);
+}
+
+
+static void patchlistaux (FuncState *fs, int list, int vtarget, int reg,
+                          int dtarget) {
+  while (list != NO_JUMP) {
+    int next = getjump(fs, list);
+    if (patchtestreg(fs, list, reg))
+      fixjump(fs, list, vtarget);
+    else
+      fixjump(fs, list, dtarget);  /* jump to default target */
+    list = next;
+  }
+}
+
+
+static void dischargejpc (FuncState *fs) {
+  patchlistaux(fs, fs->jpc, fs->pc, NO_REG, fs->pc);
+  fs->jpc = NO_JUMP;
+}
+
+
+void luaK_patchlist (FuncState *fs, int list, int target) {
+  if (target == fs->pc)
+    luaK_patchtohere(fs, list);
+  else {
+    lua_assert(target < fs->pc);
+    patchlistaux(fs, list, target, NO_REG, target);
+  }
+}
+
+
+void luaK_patchtohere (FuncState *fs, int list) {
+  luaK_getlabel(fs);
+  luaK_concat(fs, &fs->jpc, list);
+}
+
+
+void luaK_concat (FuncState *fs, int *l1, int l2) {
+  if (l2 == NO_JUMP) return;
+  else if (*l1 == NO_JUMP)
+    *l1 = l2;
+  else {
+    int list = *l1;
+    int next;
+    while ((next = getjump(fs, list)) != NO_JUMP)  /* find last element */
+      list = next;
+    fixjump(fs, list, l2);
+  }
+}
+
+
+void luaK_checkstack (FuncState *fs, int n) {
+  int newstack = fs->freereg + n;
+  if (newstack > fs->f->maxstacksize) {
+    if (newstack >= MAXSTACK)
+      luaX_syntaxerror(fs->ls, "function or expression too complex");
+    fs->f->maxstacksize = cast_byte(newstack);
+  }
+}
+
+
+void luaK_reserveregs (FuncState *fs, int n) {
+  luaK_checkstack(fs, n);
+  fs->freereg += n;
+}
+
+
+static void freereg (FuncState *fs, int reg) {
+  if (!ISK(reg) && reg >= fs->nactvar) {
+    fs->freereg--;
+    lua_assert(reg == fs->freereg);
+  }
+}
+
+
+static void freeexp (FuncState *fs, expdesc *e) {
+  if (e->k == VNONRELOC)
+    freereg(fs, e->u.s.info);
+}
+
+
+static int addk (FuncState *fs, TValue *k, TValue *v) {
+  lua_State *L = fs->L;
+  TValue *idx = luaH_set(L, fs->h, k);
+  Proto *f = fs->f;
+  int oldsize = f->sizek;
+  if (ttisnumber(idx)) {
+    lua_assert(luaO_rawequalObj(&fs->f->k[cast_int(nvalue(idx))], v));
+    return cast_int(nvalue(idx));
+  }
+  else {  /* constant not found; create a new entry */
+    setnvalue(idx, cast_num(fs->nk));
+    luaM_growvector(L, f->k, fs->nk, f->sizek, TValue,
+                    MAXARG_Bx, "constant table overflow");
+    while (oldsize < f->sizek) setnilvalue(&f->k[oldsize++]);
+    setobj(L, &f->k[fs->nk], v);
+    luaC_barrier(L, f, v);
+    return fs->nk++;
+  }
+}
+
+
+int luaK_stringK (FuncState *fs, TString *s) {
+  TValue o;
+  setsvalue(fs->L, &o, s);
+  return addk(fs, &o, &o);
+}
+
+
+int luaK_numberK (FuncState *fs, lua_Number r) {
+  TValue o;
+  setnvalue(&o, r);
+  return addk(fs, &o, &o);
+}
+
+
+static int boolK (FuncState *fs, int b) {
+  TValue o;
+  setbvalue(&o, b);
+  return addk(fs, &o, &o);
+}
+
+
+static int nilK (FuncState *fs) {
+  TValue k, v;
+  setnilvalue(&v);
+  /* cannot use nil as key; instead use table itself to represent nil */
+  sethvalue(fs->L, &k, fs->h);
+  return addk(fs, &k, &v);
+}
+
+
+void luaK_setreturns (FuncState *fs, expdesc *e, int nresults) {
+  if (e->k == VCALL) {  /* expression is an open function call? */
+    SETARG_C(getcode(fs, e), nresults+1);
+  }
+  else if (e->k == VVARARG) {
+    SETARG_B(getcode(fs, e), nresults+1);
+    SETARG_A(getcode(fs, e), fs->freereg);
+    luaK_reserveregs(fs, 1);
+  }
+}
+
+
+void luaK_setoneret (FuncState *fs, expdesc *e) {
+  if (e->k == VCALL) {  /* expression is an open function call? */
+    e->k = VNONRELOC;
+    e->u.s.info = GETARG_A(getcode(fs, e));
+  }
+  else if (e->k == VVARARG) {
+    SETARG_B(getcode(fs, e), 2);
+    e->k = VRELOCABLE;  /* can relocate its simple result */
+  }
+}
+
+
+void luaK_dischargevars (FuncState *fs, expdesc *e) {
+  switch (e->k) {
+    case VLOCAL: {
+      e->k = VNONRELOC;
+      break;
+    }
+    case VUPVAL: {
+      e->u.s.info = luaK_codeABC(fs, OP_GETUPVAL, 0, e->u.s.info, 0);
+      e->k = VRELOCABLE;
+      break;
+    }
+    case VGLOBAL: {
+      e->u.s.info = luaK_codeABx(fs, OP_GETGLOBAL, 0, e->u.s.info);
+      e->k = VRELOCABLE;
+      break;
+    }
+    case VINDEXED: {
+      freereg(fs, e->u.s.aux);
+      freereg(fs, e->u.s.info);
+      e->u.s.info = luaK_codeABC(fs, OP_GETTABLE, 0, e->u.s.info, e->u.s.aux);
+      e->k = VRELOCABLE;
+      break;
+    }
+    case VVARARG:
+    case VCALL: {
+      luaK_setoneret(fs, e);
+      break;
+    }
+    default: break;  /* there is one value available (somewhere) */
+  }
+}
+
+
+static int code_label (FuncState *fs, int A, int b, int jump) {
+  luaK_getlabel(fs);  /* those instructions may be jump targets */
+  return luaK_codeABC(fs, OP_LOADBOOL, A, b, jump);
+}
+
+
+static void discharge2reg (FuncState *fs, expdesc *e, int reg) {
+  luaK_dischargevars(fs, e);
+  switch (e->k) {
+    case VNIL: {
+      luaK_nil(fs, reg, 1);
+      break;
+    }
+    case VFALSE:  case VTRUE: {
+      luaK_codeABC(fs, OP_LOADBOOL, reg, e->k == VTRUE, 0);
+      break;
+    }
+    case VK: {
+      luaK_codeABx(fs, OP_LOADK, reg, e->u.s.info);
+      break;
+    }
+    case VKNUM: {
+      luaK_codeABx(fs, OP_LOADK, reg, luaK_numberK(fs, e->u.nval));
+      break;
+    }
+    case VRELOCABLE: {
+      Instruction *pc = &getcode(fs, e);
+      SETARG_A(*pc, reg);
+      break;
+    }
+    case VNONRELOC: {
+      if (reg != e->u.s.info)
+        luaK_codeABC(fs, OP_MOVE, reg, e->u.s.info, 0);
+      break;
+    }
+    default: {
+      lua_assert(e->k == VVOID || e->k == VJMP);
+      return;  /* nothing to do... */
+    }
+  }
+  e->u.s.info = reg;
+  e->k = VNONRELOC;
+}
+
+
+static void discharge2anyreg (FuncState *fs, expdesc *e) {
+  if (e->k != VNONRELOC) {
+    luaK_reserveregs(fs, 1);
+    discharge2reg(fs, e, fs->freereg-1);
+  }
+}
+
+
+static void exp2reg (FuncState *fs, expdesc *e, int reg) {
+  discharge2reg(fs, e, reg);
+  if (e->k == VJMP)
+    luaK_concat(fs, &e->t, e->u.s.info);  /* put this jump in `t' list */
+  if (hasjumps(e)) {
+    int final;  /* position after whole expression */
+    int p_f = NO_JUMP;  /* position of an eventual LOAD false */
+    int p_t = NO_JUMP;  /* position of an eventual LOAD true */
+    if (need_value(fs, e->t) || need_value(fs, e->f)) {
+      int fj = (e->k == VJMP) ? NO_JUMP : luaK_jump(fs);
+      p_f = code_label(fs, reg, 0, 1);
+      p_t = code_label(fs, reg, 1, 0);
+      luaK_patchtohere(fs, fj);
+    }
+    final = luaK_getlabel(fs);
+    patchlistaux(fs, e->f, final, reg, p_f);
+    patchlistaux(fs, e->t, final, reg, p_t);
+  }
+  e->f = e->t = NO_JUMP;
+  e->u.s.info = reg;
+  e->k = VNONRELOC;
+}
+
+
+void luaK_exp2nextreg (FuncState *fs, expdesc *e) {
+  luaK_dischargevars(fs, e);
+  freeexp(fs, e);
+  luaK_reserveregs(fs, 1);
+  exp2reg(fs, e, fs->freereg - 1);
+}
+
+
+int luaK_exp2anyreg (FuncState *fs, expdesc *e) {
+  luaK_dischargevars(fs, e);
+  if (e->k == VNONRELOC) {
+    if (!hasjumps(e)) return e->u.s.info;  /* exp is already in a register */
+    if (e->u.s.info >= fs->nactvar) {  /* reg. is not a local? */
+      exp2reg(fs, e, e->u.s.info);  /* put value on it */
+      return e->u.s.info;
+    }
+  }
+  luaK_exp2nextreg(fs, e);  /* default */
+  return e->u.s.info;
+}
+
+
+void luaK_exp2val (FuncState *fs, expdesc *e) {
+  if (hasjumps(e))
+    luaK_exp2anyreg(fs, e);
+  else
+    luaK_dischargevars(fs, e);
+}
+
+
+int luaK_exp2RK (FuncState *fs, expdesc *e) {
+  luaK_exp2val(fs, e);
+  switch (e->k) {
+    case VKNUM:
+    case VTRUE:
+    case VFALSE:
+    case VNIL: {
+      if (fs->nk <= MAXINDEXRK) {  /* constant fit in RK operand? */
+        e->u.s.info = (e->k == VNIL)  ? nilK(fs) :
+                      (e->k == VKNUM) ? luaK_numberK(fs, e->u.nval) :
+                                        boolK(fs, (e->k == VTRUE));
+        e->k = VK;
+        return RKASK(e->u.s.info);
+      }
+      else break;
+    }
+    case VK: {
+      if (e->u.s.info <= MAXINDEXRK)  /* constant fit in argC? */
+        return RKASK(e->u.s.info);
+      else break;
+    }
+    default: break;
+  }
+  /* not a constant in the right range: put it in a register */
+  return luaK_exp2anyreg(fs, e);
+}
+
+
+void luaK_storevar (FuncState *fs, expdesc *var, expdesc *ex) {
+  switch (var->k) {
+    case VLOCAL: {
+      freeexp(fs, ex);
+      exp2reg(fs, ex, var->u.s.info);
+      return;
+    }
+    case VUPVAL: {
+      int e = luaK_exp2anyreg(fs, ex);
+      luaK_codeABC(fs, OP_SETUPVAL, e, var->u.s.info, 0);
+      break;
+    }
+    case VGLOBAL: {
+      int e = luaK_exp2anyreg(fs, ex);
+      luaK_codeABx(fs, OP_SETGLOBAL, e, var->u.s.info);
+      break;
+    }
+    case VINDEXED: {
+      int e = luaK_exp2RK(fs, ex);
+      luaK_codeABC(fs, OP_SETTABLE, var->u.s.info, var->u.s.aux, e);
+      break;
+    }
+    default: {
+      lua_assert(0);  /* invalid var kind to store */
+      break;
+    }
+  }
+  freeexp(fs, ex);
+}
+
+
+void luaK_self (FuncState *fs, expdesc *e, expdesc *key) {
+  int func;
+  luaK_exp2anyreg(fs, e);
+  freeexp(fs, e);
+  func = fs->freereg;
+  luaK_reserveregs(fs, 2);
+  luaK_codeABC(fs, OP_SELF, func, e->u.s.info, luaK_exp2RK(fs, key));
+  freeexp(fs, key);
+  e->u.s.info = func;
+  e->k = VNONRELOC;
+}
+
+
+static void invertjump (FuncState *fs, expdesc *e) {
+  Instruction *pc = getjumpcontrol(fs, e->u.s.info);
+  lua_assert(testTMode(GET_OPCODE(*pc)) && GET_OPCODE(*pc) != OP_TESTSET &&
+                                           GET_OPCODE(*pc) != OP_TEST);
+  SETARG_A(*pc, !(GETARG_A(*pc)));
+}
+
+
+static int jumponcond (FuncState *fs, expdesc *e, int cond) {
+  if (e->k == VRELOCABLE) {
+    Instruction ie = getcode(fs, e);
+    if (GET_OPCODE(ie) == OP_NOT) {
+      fs->pc--;  /* remove previous OP_NOT */
+      return condjump(fs, OP_TEST, GETARG_B(ie), 0, !cond);
+    }
+    /* else go through */
+  }
+  discharge2anyreg(fs, e);
+  freeexp(fs, e);
+  return condjump(fs, OP_TESTSET, NO_REG, e->u.s.info, cond);
+}
+
+
+void luaK_goiftrue (FuncState *fs, expdesc *e) {
+  int pc;  /* pc of last jump */
+  luaK_dischargevars(fs, e);
+  switch (e->k) {
+    case VK: case VKNUM: case VTRUE: {
+      pc = NO_JUMP;  /* always true; do nothing */
+      break;
+    }
+    case VFALSE: {
+      pc = luaK_jump(fs);  /* always jump */
+      break;
+    }
+    case VJMP: {
+      invertjump(fs, e);
+      pc = e->u.s.info;
+      break;
+    }
+    default: {
+      pc = jumponcond(fs, e, 0);
+      break;
+    }
+  }
+  luaK_concat(fs, &e->f, pc);  /* insert last jump in `f' list */
+  luaK_patchtohere(fs, e->t);
+  e->t = NO_JUMP;
+}
+
+
+static void luaK_goiffalse (FuncState *fs, expdesc *e) {
+  int pc;  /* pc of last jump */
+  luaK_dischargevars(fs, e);
+  switch (e->k) {
+    case VNIL: case VFALSE: {
+      pc = NO_JUMP;  /* always false; do nothing */
+      break;
+    }
+    case VTRUE: {
+      pc = luaK_jump(fs);  /* always jump */
+      break;
+    }
+    case VJMP: {
+      pc = e->u.s.info;
+      break;
+    }
+    default: {
+      pc = jumponcond(fs, e, 1);
+      break;
+    }
+  }
+  luaK_concat(fs, &e->t, pc);  /* insert last jump in `t' list */
+  luaK_patchtohere(fs, e->f);
+  e->f = NO_JUMP;
+}
+
+
+static void codenot (FuncState *fs, expdesc *e) {
+  luaK_dischargevars(fs, e);
+  switch (e->k) {
+    case VNIL: case VFALSE: {
+      e->k = VTRUE;
+      break;
+    }
+    case VK: case VKNUM: case VTRUE: {
+      e->k = VFALSE;
+      break;
+    }
+    case VJMP: {
+      invertjump(fs, e);
+      break;
+    }
+    case VRELOCABLE:
+    case VNONRELOC: {
+      discharge2anyreg(fs, e);
+      freeexp(fs, e);
+      e->u.s.info = luaK_codeABC(fs, OP_NOT, 0, e->u.s.info, 0);
+      e->k = VRELOCABLE;
+      break;
+    }
+    default: {
+      lua_assert(0);  /* cannot happen */
+      break;
+    }
+  }
+  /* interchange true and false lists */
+  { int temp = e->f; e->f = e->t; e->t = temp; }
+  removevalues(fs, e->f);
+  removevalues(fs, e->t);
+}
+
+
+void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k) {
+  t->u.s.aux = luaK_exp2RK(fs, k);
+  t->k = VINDEXED;
+}
+
+
+static int constfolding (OpCode op, expdesc *e1, expdesc *e2) {
+  lua_Number v1, v2, r;
+  if (!isnumeral(e1) || !isnumeral(e2)) return 0;
+  v1 = e1->u.nval;
+  v2 = e2->u.nval;
+  switch (op) {
+    case OP_ADD: r = luai_numadd(v1, v2); break;
+    case OP_SUB: r = luai_numsub(v1, v2); break;
+    case OP_MUL: r = luai_nummul(v1, v2); break;
+    case OP_DIV:
+      if (v2 == 0) return 0;  /* do not attempt to divide by 0 */
+      r = luai_numdiv(v1, v2); break;
+    case OP_MOD:
+      if (v2 == 0) return 0;  /* do not attempt to divide by 0 */
+      r = luai_nummod(v1, v2); break;
+    case OP_POW: r = luai_numpow(v1, v2); break;
+    case OP_UNM: r = luai_numunm(v1); break;
+    case OP_LEN: return 0;  /* no constant folding for 'len' */
+    default: lua_assert(0); r = 0; break;
+  }
+  if (luai_numisnan(r)) return 0;  /* do not attempt to produce NaN */
+  e1->u.nval = r;
+  return 1;
+}
+
+
+static void codearith (FuncState *fs, OpCode op, expdesc *e1, expdesc *e2) {
+  if (constfolding(op, e1, e2))
+    return;
+  else {
+    int o2 = (op != OP_UNM && op != OP_LEN) ? luaK_exp2RK(fs, e2) : 0;
+    int o1 = luaK_exp2RK(fs, e1);
+    if (o1 > o2) {
+      freeexp(fs, e1);
+      freeexp(fs, e2);
+    }
+    else {
+      freeexp(fs, e2);
+      freeexp(fs, e1);
+    }
+    e1->u.s.info = luaK_codeABC(fs, op, 0, o1, o2);
+    e1->k = VRELOCABLE;
+  }
+}
+
+
+static void codecomp (FuncState *fs, OpCode op, int cond, expdesc *e1,
+                                                          expdesc *e2) {
+  int o1 = luaK_exp2RK(fs, e1);
+  int o2 = luaK_exp2RK(fs, e2);
+  freeexp(fs, e2);
+  freeexp(fs, e1);
+  if (cond == 0 && op != OP_EQ) {
+    int temp;  /* exchange args to replace by `<' or `<=' */
+    temp = o1; o1 = o2; o2 = temp;  /* o1 <==> o2 */
+    cond = 1;
+  }
+  e1->u.s.info = condjump(fs, op, cond, o1, o2);
+  e1->k = VJMP;
+}
+
+
+void luaK_prefix (FuncState *fs, UnOpr op, expdesc *e) {
+  expdesc e2;
+  e2.t = e2.f = NO_JUMP; e2.k = VKNUM; e2.u.nval = 0;
+  switch (op) {
+    case OPR_MINUS: {
+      if (!isnumeral(e))
+        luaK_exp2anyreg(fs, e);  /* cannot operate on non-numeric constants */
+      codearith(fs, OP_UNM, e, &e2);
+      break;
+    }
+    case OPR_NOT: codenot(fs, e); break;
+    case OPR_LEN: {
+      luaK_exp2anyreg(fs, e);  /* cannot operate on constants */
+      codearith(fs, OP_LEN, e, &e2);
+      break;
+    }
+    default: lua_assert(0);
+  }
+}
+
+
+void luaK_infix (FuncState *fs, BinOpr op, expdesc *v) {
+  switch (op) {
+    case OPR_AND: {
+      luaK_goiftrue(fs, v);
+      break;
+    }
+    case OPR_OR: {
+      luaK_goiffalse(fs, v);
+      break;
+    }
+    case OPR_CONCAT: {
+      luaK_exp2nextreg(fs, v);  /* operand must be on the `stack' */
+      break;
+    }
+    case OPR_ADD: case OPR_SUB: case OPR_MUL: case OPR_DIV:
+    case OPR_MOD: case OPR_POW: {
+      if (!isnumeral(v)) luaK_exp2RK(fs, v);
+      break;
+    }
+    default: {
+      luaK_exp2RK(fs, v);
+      break;
+    }
+  }
+}
+
+
+void luaK_posfix (FuncState *fs, BinOpr op, expdesc *e1, expdesc *e2) {
+  switch (op) {
+    case OPR_AND: {
+      lua_assert(e1->t == NO_JUMP);  /* list must be closed */
+      luaK_dischargevars(fs, e2);
+      luaK_concat(fs, &e2->f, e1->f);
+      *e1 = *e2;
+      break;
+    }
+    case OPR_OR: {
+      lua_assert(e1->f == NO_JUMP);  /* list must be closed */
+      luaK_dischargevars(fs, e2);
+      luaK_concat(fs, &e2->t, e1->t);
+      *e1 = *e2;
+      break;
+    }
+    case OPR_CONCAT: {
+      luaK_exp2val(fs, e2);
+      if (e2->k == VRELOCABLE && GET_OPCODE(getcode(fs, e2)) == OP_CONCAT) {
+        lua_assert(e1->u.s.info == GETARG_B(getcode(fs, e2))-1);
+        freeexp(fs, e1);
+        SETARG_B(getcode(fs, e2), e1->u.s.info);
+        e1->k = VRELOCABLE; e1->u.s.info = e2->u.s.info;
+      }
+      else {
+        luaK_exp2nextreg(fs, e2);  /* operand must be on the 'stack' */
+        codearith(fs, OP_CONCAT, e1, e2);
+      }
+      break;
+    }
+    case OPR_ADD: codearith(fs, OP_ADD, e1, e2); break;
+    case OPR_SUB: codearith(fs, OP_SUB, e1, e2); break;
+    case OPR_MUL: codearith(fs, OP_MUL, e1, e2); break;
+    case OPR_DIV: codearith(fs, OP_DIV, e1, e2); break;
+    case OPR_MOD: codearith(fs, OP_MOD, e1, e2); break;
+    case OPR_POW: codearith(fs, OP_POW, e1, e2); break;
+    case OPR_EQ: codecomp(fs, OP_EQ, 1, e1, e2); break;
+    case OPR_NE: codecomp(fs, OP_EQ, 0, e1, e2); break;
+    case OPR_LT: codecomp(fs, OP_LT, 1, e1, e2); break;
+    case OPR_LE: codecomp(fs, OP_LE, 1, e1, e2); break;
+    case OPR_GT: codecomp(fs, OP_LT, 0, e1, e2); break;
+    case OPR_GE: codecomp(fs, OP_LE, 0, e1, e2); break;
+    default: lua_assert(0);
+  }
+}
+
+
+void luaK_fixline (FuncState *fs, int line) {
+  fs->f->lineinfo[fs->pc - 1] = line;
+}
+
+
+static int luaK_code (FuncState *fs, Instruction i, int line) {
+  Proto *f = fs->f;
+  dischargejpc(fs);  /* `pc' will change */
+  /* put new instruction in code array */
+  luaM_growvector(fs->L, f->code, fs->pc, f->sizecode, Instruction,
+                  MAX_INT, "code size overflow");
+  f->code[fs->pc] = i;
+  /* save corresponding line information */
+  luaM_growvector(fs->L, f->lineinfo, fs->pc, f->sizelineinfo, int,
+                  MAX_INT, "code size overflow");
+  f->lineinfo[fs->pc] = line;
+  return fs->pc++;
+}
+
+
+int luaK_codeABC (FuncState *fs, OpCode o, int a, int b, int c) {
+  lua_assert(getOpMode(o) == iABC);
+  lua_assert(getBMode(o) != OpArgN || b == 0);
+  lua_assert(getCMode(o) != OpArgN || c == 0);
+  return luaK_code(fs, CREATE_ABC(o, a, b, c), fs->ls->lastline);
+}
+
+
+int luaK_codeABx (FuncState *fs, OpCode o, int a, unsigned int bc) {
+  lua_assert(getOpMode(o) == iABx || getOpMode(o) == iAsBx);
+  lua_assert(getCMode(o) == OpArgN);
+  return luaK_code(fs, CREATE_ABx(o, a, bc), fs->ls->lastline);
+}
+
+
+void luaK_setlist (FuncState *fs, int base, int nelems, int tostore) {
+  int c =  (nelems - 1)/LFIELDS_PER_FLUSH + 1;
+  int b = (tostore == LUA_MULTRET) ? 0 : tostore;
+  lua_assert(tostore != 0);
+  if (c <= MAXARG_C)
+    luaK_codeABC(fs, OP_SETLIST, base, b, c);
+  else {
+    luaK_codeABC(fs, OP_SETLIST, base, b, 0);
+    luaK_code(fs, cast(Instruction, c), fs->ls->lastline);
+  }
+  fs->freereg = base + 1;  /* free registers with list values */
+}
+
diff --git a/com32/lua/src/lcode.h b/com32/lua/src/lcode.h
new file mode 100644
index 00000000..b941c607
--- /dev/null
+++ b/com32/lua/src/lcode.h
@@ -0,0 +1,76 @@
+/*
+** $Id: lcode.h,v 1.48.1.1 2007/12/27 13:02:25 roberto Exp $
+** Code generator for Lua
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lcode_h
+#define lcode_h
+
+#include "llex.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lparser.h"
+
+
+/*
+** Marks the end of a patch list. It is an invalid value both as an absolute
+** address, and as a list link (would link an element to itself).
+*/
+#define NO_JUMP (-1)
+
+
+/*
+** grep "ORDER OPR" if you change these enums
+*/
+typedef enum BinOpr {
+  OPR_ADD, OPR_SUB, OPR_MUL, OPR_DIV, OPR_MOD, OPR_POW,
+  OPR_CONCAT,
+  OPR_NE, OPR_EQ,
+  OPR_LT, OPR_LE, OPR_GT, OPR_GE,
+  OPR_AND, OPR_OR,
+  OPR_NOBINOPR
+} BinOpr;
+
+
+typedef enum UnOpr { OPR_MINUS, OPR_NOT, OPR_LEN, OPR_NOUNOPR } UnOpr;
+
+
+#define getcode(fs,e)	((fs)->f->code[(e)->u.s.info])
+
+#define luaK_codeAsBx(fs,o,A,sBx)	luaK_codeABx(fs,o,A,(sBx)+MAXARG_sBx)
+
+#define luaK_setmultret(fs,e)	luaK_setreturns(fs, e, LUA_MULTRET)
+
+LUAI_FUNC int luaK_codeABx (FuncState *fs, OpCode o, int A, unsigned int Bx);
+LUAI_FUNC int luaK_codeABC (FuncState *fs, OpCode o, int A, int B, int C);
+LUAI_FUNC void luaK_fixline (FuncState *fs, int line);
+LUAI_FUNC void luaK_nil (FuncState *fs, int from, int n);
+LUAI_FUNC void luaK_reserveregs (FuncState *fs, int n);
+LUAI_FUNC void luaK_checkstack (FuncState *fs, int n);
+LUAI_FUNC int luaK_stringK (FuncState *fs, TString *s);
+LUAI_FUNC int luaK_numberK (FuncState *fs, lua_Number r);
+LUAI_FUNC void luaK_dischargevars (FuncState *fs, expdesc *e);
+LUAI_FUNC int luaK_exp2anyreg (FuncState *fs, expdesc *e);
+LUAI_FUNC void luaK_exp2nextreg (FuncState *fs, expdesc *e);
+LUAI_FUNC void luaK_exp2val (FuncState *fs, expdesc *e);
+LUAI_FUNC int luaK_exp2RK (FuncState *fs, expdesc *e);
+LUAI_FUNC void luaK_self (FuncState *fs, expdesc *e, expdesc *key);
+LUAI_FUNC void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k);
+LUAI_FUNC void luaK_goiftrue (FuncState *fs, expdesc *e);
+LUAI_FUNC void luaK_storevar (FuncState *fs, expdesc *var, expdesc *e);
+LUAI_FUNC void luaK_setreturns (FuncState *fs, expdesc *e, int nresults);
+LUAI_FUNC void luaK_setoneret (FuncState *fs, expdesc *e);
+LUAI_FUNC int luaK_jump (FuncState *fs);
+LUAI_FUNC void luaK_ret (FuncState *fs, int first, int nret);
+LUAI_FUNC void luaK_patchlist (FuncState *fs, int list, int target);
+LUAI_FUNC void luaK_patchtohere (FuncState *fs, int list);
+LUAI_FUNC void luaK_concat (FuncState *fs, int *l1, int l2);
+LUAI_FUNC int luaK_getlabel (FuncState *fs);
+LUAI_FUNC void luaK_prefix (FuncState *fs, UnOpr op, expdesc *v);
+LUAI_FUNC void luaK_infix (FuncState *fs, BinOpr op, expdesc *v);
+LUAI_FUNC void luaK_posfix (FuncState *fs, BinOpr op, expdesc *v1, expdesc *v2);
+LUAI_FUNC void luaK_setlist (FuncState *fs, int base, int nelems, int tostore);
+
+
+#endif
diff --git a/com32/lua/src/ldblib.c b/com32/lua/src/ldblib.c
new file mode 100644
index 00000000..67de1222
--- /dev/null
+++ b/com32/lua/src/ldblib.c
@@ -0,0 +1,397 @@
+/*
+** $Id: ldblib.c,v 1.104.1.3 2008/01/21 13:11:21 roberto Exp $
+** Interface from Lua to its debug API
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define ldblib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+
+static int db_getregistry (lua_State *L) {
+  lua_pushvalue(L, LUA_REGISTRYINDEX);
+  return 1;
+}
+
+
+static int db_getmetatable (lua_State *L) {
+  luaL_checkany(L, 1);
+  if (!lua_getmetatable(L, 1)) {
+    lua_pushnil(L);  /* no metatable */
+  }
+  return 1;
+}
+
+
+static int db_setmetatable (lua_State *L) {
+  int t = lua_type(L, 2);
+  luaL_argcheck(L, t == LUA_TNIL || t == LUA_TTABLE, 2,
+                    "nil or table expected");
+  lua_settop(L, 2);
+  lua_pushboolean(L, lua_setmetatable(L, 1));
+  return 1;
+}
+
+
+static int db_getfenv (lua_State *L) {
+  lua_getfenv(L, 1);
+  return 1;
+}
+
+
+static int db_setfenv (lua_State *L) {
+  luaL_checktype(L, 2, LUA_TTABLE);
+  lua_settop(L, 2);
+  if (lua_setfenv(L, 1) == 0)
+    luaL_error(L, LUA_QL("setfenv")
+                  " cannot change environment of given object");
+  return 1;
+}
+
+
+static void settabss (lua_State *L, const char *i, const char *v) {
+  lua_pushstring(L, v);
+  lua_setfield(L, -2, i);
+}
+
+
+static void settabsi (lua_State *L, const char *i, int v) {
+  lua_pushinteger(L, v);
+  lua_setfield(L, -2, i);
+}
+
+
+static lua_State *getthread (lua_State *L, int *arg) {
+  if (lua_isthread(L, 1)) {
+    *arg = 1;
+    return lua_tothread(L, 1);
+  }
+  else {
+    *arg = 0;
+    return L;
+  }
+}
+
+
+static void treatstackoption (lua_State *L, lua_State *L1, const char *fname) {
+  if (L == L1) {
+    lua_pushvalue(L, -2);
+    lua_remove(L, -3);
+  }
+  else
+    lua_xmove(L1, L, 1);
+  lua_setfield(L, -2, fname);
+}
+
+
+static int db_getinfo (lua_State *L) {
+  lua_Debug ar;
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  const char *options = luaL_optstring(L, arg+2, "flnSu");
+  if (lua_isnumber(L, arg+1)) {
+    if (!lua_getstack(L1, (int)lua_tointeger(L, arg+1), &ar)) {
+      lua_pushnil(L);  /* level out of range */
+      return 1;
+    }
+  }
+  else if (lua_isfunction(L, arg+1)) {
+    lua_pushfstring(L, ">%s", options);
+    options = lua_tostring(L, -1);
+    lua_pushvalue(L, arg+1);
+    lua_xmove(L, L1, 1);
+  }
+  else
+    return luaL_argerror(L, arg+1, "function or level expected");
+  if (!lua_getinfo(L1, options, &ar))
+    return luaL_argerror(L, arg+2, "invalid option");
+  lua_createtable(L, 0, 2);
+  if (strchr(options, 'S')) {
+    settabss(L, "source", ar.source);
+    settabss(L, "short_src", ar.short_src);
+    settabsi(L, "linedefined", ar.linedefined);
+    settabsi(L, "lastlinedefined", ar.lastlinedefined);
+    settabss(L, "what", ar.what);
+  }
+  if (strchr(options, 'l'))
+    settabsi(L, "currentline", ar.currentline);
+  if (strchr(options, 'u'))
+    settabsi(L, "nups", ar.nups);
+  if (strchr(options, 'n')) {
+    settabss(L, "name", ar.name);
+    settabss(L, "namewhat", ar.namewhat);
+  }
+  if (strchr(options, 'L'))
+    treatstackoption(L, L1, "activelines");
+  if (strchr(options, 'f'))
+    treatstackoption(L, L1, "func");
+  return 1;  /* return table */
+}
+    
+
+static int db_getlocal (lua_State *L) {
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  lua_Debug ar;
+  const char *name;
+  if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar))  /* out of range? */
+    return luaL_argerror(L, arg+1, "level out of range");
+  name = lua_getlocal(L1, &ar, luaL_checkint(L, arg+2));
+  if (name) {
+    lua_xmove(L1, L, 1);
+    lua_pushstring(L, name);
+    lua_pushvalue(L, -2);
+    return 2;
+  }
+  else {
+    lua_pushnil(L);
+    return 1;
+  }
+}
+
+
+static int db_setlocal (lua_State *L) {
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  lua_Debug ar;
+  if (!lua_getstack(L1, luaL_checkint(L, arg+1), &ar))  /* out of range? */
+    return luaL_argerror(L, arg+1, "level out of range");
+  luaL_checkany(L, arg+3);
+  lua_settop(L, arg+3);
+  lua_xmove(L, L1, 1);
+  lua_pushstring(L, lua_setlocal(L1, &ar, luaL_checkint(L, arg+2)));
+  return 1;
+}
+
+
+static int auxupvalue (lua_State *L, int get) {
+  const char *name;
+  int n = luaL_checkint(L, 2);
+  luaL_checktype(L, 1, LUA_TFUNCTION);
+  if (lua_iscfunction(L, 1)) return 0;  /* cannot touch C upvalues from Lua */
+  name = get ? lua_getupvalue(L, 1, n) : lua_setupvalue(L, 1, n);
+  if (name == NULL) return 0;
+  lua_pushstring(L, name);
+  lua_insert(L, -(get+1));
+  return get + 1;
+}
+
+
+static int db_getupvalue (lua_State *L) {
+  return auxupvalue(L, 1);
+}
+
+
+static int db_setupvalue (lua_State *L) {
+  luaL_checkany(L, 3);
+  return auxupvalue(L, 0);
+}
+
+
+
+static const char KEY_HOOK = 'h';
+
+
+static void hookf (lua_State *L, lua_Debug *ar) {
+  static const char *const hooknames[] =
+    {"call", "return", "line", "count", "tail return"};
+  lua_pushlightuserdata(L, (void *)&KEY_HOOK);
+  lua_rawget(L, LUA_REGISTRYINDEX);
+  lua_pushlightuserdata(L, L);
+  lua_rawget(L, -2);
+  if (lua_isfunction(L, -1)) {
+    lua_pushstring(L, hooknames[(int)ar->event]);
+    if (ar->currentline >= 0)
+      lua_pushinteger(L, ar->currentline);
+    else lua_pushnil(L);
+    lua_assert(lua_getinfo(L, "lS", ar));
+    lua_call(L, 2, 0);
+  }
+}
+
+
+static int makemask (const char *smask, int count) {
+  int mask = 0;
+  if (strchr(smask, 'c')) mask |= LUA_MASKCALL;
+  if (strchr(smask, 'r')) mask |= LUA_MASKRET;
+  if (strchr(smask, 'l')) mask |= LUA_MASKLINE;
+  if (count > 0) mask |= LUA_MASKCOUNT;
+  return mask;
+}
+
+
+static char *unmakemask (int mask, char *smask) {
+  int i = 0;
+  if (mask & LUA_MASKCALL) smask[i++] = 'c';
+  if (mask & LUA_MASKRET) smask[i++] = 'r';
+  if (mask & LUA_MASKLINE) smask[i++] = 'l';
+  smask[i] = '\0';
+  return smask;
+}
+
+
+static void gethooktable (lua_State *L) {
+  lua_pushlightuserdata(L, (void *)&KEY_HOOK);
+  lua_rawget(L, LUA_REGISTRYINDEX);
+  if (!lua_istable(L, -1)) {
+    lua_pop(L, 1);
+    lua_createtable(L, 0, 1);
+    lua_pushlightuserdata(L, (void *)&KEY_HOOK);
+    lua_pushvalue(L, -2);
+    lua_rawset(L, LUA_REGISTRYINDEX);
+  }
+}
+
+
+static int db_sethook (lua_State *L) {
+  int arg, mask, count;
+  lua_Hook func;
+  lua_State *L1 = getthread(L, &arg);
+  if (lua_isnoneornil(L, arg+1)) {
+    lua_settop(L, arg+1);
+    func = NULL; mask = 0; count = 0;  /* turn off hooks */
+  }
+  else {
+    const char *smask = luaL_checkstring(L, arg+2);
+    luaL_checktype(L, arg+1, LUA_TFUNCTION);
+    count = luaL_optint(L, arg+3, 0);
+    func = hookf; mask = makemask(smask, count);
+  }
+  gethooktable(L);
+  lua_pushlightuserdata(L, L1);
+  lua_pushvalue(L, arg+1);
+  lua_rawset(L, -3);  /* set new hook */
+  lua_pop(L, 1);  /* remove hook table */
+  lua_sethook(L1, func, mask, count);  /* set hooks */
+  return 0;
+}
+
+
+static int db_gethook (lua_State *L) {
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  char buff[5];
+  int mask = lua_gethookmask(L1);
+  lua_Hook hook = lua_gethook(L1);
+  if (hook != NULL && hook != hookf)  /* external hook? */
+    lua_pushliteral(L, "external hook");
+  else {
+    gethooktable(L);
+    lua_pushlightuserdata(L, L1);
+    lua_rawget(L, -2);   /* get hook */
+    lua_remove(L, -2);  /* remove hook table */
+  }
+  lua_pushstring(L, unmakemask(mask, buff));
+  lua_pushinteger(L, lua_gethookcount(L1));
+  return 3;
+}
+
+
+static int db_debug (lua_State *L) {
+  for (;;) {
+    char buffer[250];
+    fputs("lua_debug> ", stderr);
+    if (fgets(buffer, sizeof(buffer), stdin) == 0 ||
+        strcmp(buffer, "cont\n") == 0)
+      return 0;
+    if (luaL_loadbuffer(L, buffer, strlen(buffer), "=(debug command)") ||
+        lua_pcall(L, 0, 0, 0)) {
+      fputs(lua_tostring(L, -1), stderr);
+      fputs("\n", stderr);
+    }
+    lua_settop(L, 0);  /* remove eventual returns */
+  }
+}
+
+
+#define LEVELS1	12	/* size of the first part of the stack */
+#define LEVELS2	10	/* size of the second part of the stack */
+
+static int db_errorfb (lua_State *L) {
+  int level;
+  int firstpart = 1;  /* still before eventual `...' */
+  int arg;
+  lua_State *L1 = getthread(L, &arg);
+  lua_Debug ar;
+  if (lua_isnumber(L, arg+2)) {
+    level = (int)lua_tointeger(L, arg+2);
+    lua_pop(L, 1);
+  }
+  else
+    level = (L == L1) ? 1 : 0;  /* level 0 may be this own function */
+  if (lua_gettop(L) == arg)
+    lua_pushliteral(L, "");
+  else if (!lua_isstring(L, arg+1)) return 1;  /* message is not a string */
+  else lua_pushliteral(L, "\n");
+  lua_pushliteral(L, "stack traceback:");
+  while (lua_getstack(L1, level++, &ar)) {
+    if (level > LEVELS1 && firstpart) {
+      /* no more than `LEVELS2' more levels? */
+      if (!lua_getstack(L1, level+LEVELS2, &ar))
+        level--;  /* keep going */
+      else {
+        lua_pushliteral(L, "\n\t...");  /* too many levels */
+        while (lua_getstack(L1, level+LEVELS2, &ar))  /* find last levels */
+          level++;
+      }
+      firstpart = 0;
+      continue;
+    }
+    lua_pushliteral(L, "\n\t");
+    lua_getinfo(L1, "Snl", &ar);
+    lua_pushfstring(L, "%s:", ar.short_src);
+    if (ar.currentline > 0)
+      lua_pushfstring(L, "%d:", ar.currentline);
+    if (*ar.namewhat != '\0')  /* is there a name? */
+        lua_pushfstring(L, " in function " LUA_QS, ar.name);
+    else {
+      if (*ar.what == 'm')  /* main? */
+        lua_pushfstring(L, " in main chunk");
+      else if (*ar.what == 'C' || *ar.what == 't')
+        lua_pushliteral(L, " ?");  /* C function or tail call */
+      else
+        lua_pushfstring(L, " in function <%s:%d>",
+                           ar.short_src, ar.linedefined);
+    }
+    lua_concat(L, lua_gettop(L) - arg);
+  }
+  lua_concat(L, lua_gettop(L) - arg);
+  return 1;
+}
+
+
+static const luaL_Reg dblib[] = {
+  {"debug", db_debug},
+  {"getfenv", db_getfenv},
+  {"gethook", db_gethook},
+  {"getinfo", db_getinfo},
+  {"getlocal", db_getlocal},
+  {"getregistry", db_getregistry},
+  {"getmetatable", db_getmetatable},
+  {"getupvalue", db_getupvalue},
+  {"setfenv", db_setfenv},
+  {"sethook", db_sethook},
+  {"setlocal", db_setlocal},
+  {"setmetatable", db_setmetatable},
+  {"setupvalue", db_setupvalue},
+  {"traceback", db_errorfb},
+  {NULL, NULL}
+};
+
+
+LUALIB_API int luaopen_debug (lua_State *L) {
+  luaL_register(L, LUA_DBLIBNAME, dblib);
+  return 1;
+}
+
diff --git a/com32/lua/src/ldebug.c b/com32/lua/src/ldebug.c
new file mode 100644
index 00000000..9eac4a9b
--- /dev/null
+++ b/com32/lua/src/ldebug.c
@@ -0,0 +1,622 @@
+/*
+** $Id: ldebug.c,v 2.29.1.3 2007/12/28 15:32:23 roberto Exp $
+** Debug Interface
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stdarg.h>
+#include <stddef.h>
+#include <string.h>
+
+
+#define ldebug_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "lapi.h"
+#include "lcode.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+#include "lvm.h"
+
+
+
+static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name);
+
+
+static int currentpc (lua_State *L, CallInfo *ci) {
+  if (!isLua(ci)) return -1;  /* function is not a Lua function? */
+  if (ci == L->ci)
+    ci->savedpc = L->savedpc;
+  return pcRel(ci->savedpc, ci_func(ci)->l.p);
+}
+
+
+static int currentline (lua_State *L, CallInfo *ci) {
+  int pc = currentpc(L, ci);
+  if (pc < 0)
+    return -1;  /* only active lua functions have current-line information */
+  else
+    return getline(ci_func(ci)->l.p, pc);
+}
+
+
+/*
+** this function can be called asynchronous (e.g. during a signal)
+*/
+LUA_API int lua_sethook (lua_State *L, lua_Hook func, int mask, int count) {
+  if (func == NULL || mask == 0) {  /* turn off hooks? */
+    mask = 0;
+    func = NULL;
+  }
+  L->hook = func;
+  L->basehookcount = count;
+  resethookcount(L);
+  L->hookmask = cast_byte(mask);
+  return 1;
+}
+
+
+LUA_API lua_Hook lua_gethook (lua_State *L) {
+  return L->hook;
+}
+
+
+LUA_API int lua_gethookmask (lua_State *L) {
+  return L->hookmask;
+}
+
+
+LUA_API int lua_gethookcount (lua_State *L) {
+  return L->basehookcount;
+}
+
+
+LUA_API int lua_getstack (lua_State *L, int level, lua_Debug *ar) {
+  int status;
+  CallInfo *ci;
+  lua_lock(L);
+  for (ci = L->ci; level > 0 && ci > L->base_ci; ci--) {
+    level--;
+    if (f_isLua(ci))  /* Lua function? */
+      level -= ci->tailcalls;  /* skip lost tail calls */
+  }
+  if (level == 0 && ci > L->base_ci) {  /* level found? */
+    status = 1;
+    ar->i_ci = cast_int(ci - L->base_ci);
+  }
+  else if (level < 0) {  /* level is of a lost tail call? */
+    status = 1;
+    ar->i_ci = 0;
+  }
+  else status = 0;  /* no such level */
+  lua_unlock(L);
+  return status;
+}
+
+
+static Proto *getluaproto (CallInfo *ci) {
+  return (isLua(ci) ? ci_func(ci)->l.p : NULL);
+}
+
+
+static const char *findlocal (lua_State *L, CallInfo *ci, int n) {
+  const char *name;
+  Proto *fp = getluaproto(ci);
+  if (fp && (name = luaF_getlocalname(fp, n, currentpc(L, ci))) != NULL)
+    return name;  /* is a local variable in a Lua function */
+  else {
+    StkId limit = (ci == L->ci) ? L->top : (ci+1)->func;
+    if (limit - ci->base >= n && n > 0)  /* is 'n' inside 'ci' stack? */
+      return "(*temporary)";
+    else
+      return NULL;
+  }
+}
+
+
+LUA_API const char *lua_getlocal (lua_State *L, const lua_Debug *ar, int n) {
+  CallInfo *ci = L->base_ci + ar->i_ci;
+  const char *name = findlocal(L, ci, n);
+  lua_lock(L);
+  if (name)
+      luaA_pushobject(L, ci->base + (n - 1));
+  lua_unlock(L);
+  return name;
+}
+
+
+LUA_API const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n) {
+  CallInfo *ci = L->base_ci + ar->i_ci;
+  const char *name = findlocal(L, ci, n);
+  lua_lock(L);
+  if (name)
+      setobjs2s(L, ci->base + (n - 1), L->top - 1);
+  L->top--;  /* pop value */
+  lua_unlock(L);
+  return name;
+}
+
+
+static void funcinfo (lua_Debug *ar, Closure *cl) {
+  if (cl->c.isC) {
+    ar->source = "=[C]";
+    ar->linedefined = -1;
+    ar->lastlinedefined = -1;
+    ar->what = "C";
+  }
+  else {
+    ar->source = getstr(cl->l.p->source);
+    ar->linedefined = cl->l.p->linedefined;
+    ar->lastlinedefined = cl->l.p->lastlinedefined;
+    ar->what = (ar->linedefined == 0) ? "main" : "Lua";
+  }
+  luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE);
+}
+
+
+static void info_tailcall (lua_Debug *ar) {
+  ar->name = ar->namewhat = "";
+  ar->what = "tail";
+  ar->lastlinedefined = ar->linedefined = ar->currentline = -1;
+  ar->source = "=(tail call)";
+  luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE);
+  ar->nups = 0;
+}
+
+
+static void collectvalidlines (lua_State *L, Closure *f) {
+  if (f == NULL || f->c.isC) {
+    setnilvalue(L->top);
+  }
+  else {
+    Table *t = luaH_new(L, 0, 0);
+    int *lineinfo = f->l.p->lineinfo;
+    int i;
+    for (i=0; i<f->l.p->sizelineinfo; i++)
+      setbvalue(luaH_setnum(L, t, lineinfo[i]), 1);
+    sethvalue(L, L->top, t); 
+  }
+  incr_top(L);
+}
+
+
+static int auxgetinfo (lua_State *L, const char *what, lua_Debug *ar,
+                    Closure *f, CallInfo *ci) {
+  int status = 1;
+  if (f == NULL) {
+    info_tailcall(ar);
+    return status;
+  }
+  for (; *what; what++) {
+    switch (*what) {
+      case 'S': {
+        funcinfo(ar, f);
+        break;
+      }
+      case 'l': {
+        ar->currentline = (ci) ? currentline(L, ci) : -1;
+        break;
+      }
+      case 'u': {
+        ar->nups = f->c.nupvalues;
+        break;
+      }
+      case 'n': {
+        ar->namewhat = (ci) ? getfuncname(L, ci, &ar->name) : NULL;
+        if (ar->namewhat == NULL) {
+          ar->namewhat = "";  /* not found */
+          ar->name = NULL;
+        }
+        break;
+      }
+      case 'L':
+      case 'f':  /* handled by lua_getinfo */
+        break;
+      default: status = 0;  /* invalid option */
+    }
+  }
+  return status;
+}
+
+
+LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) {
+  int status;
+  Closure *f = NULL;
+  CallInfo *ci = NULL;
+  lua_lock(L);
+  if (*what == '>') {
+    StkId func = L->top - 1;
+    luai_apicheck(L, ttisfunction(func));
+    what++;  /* skip the '>' */
+    f = clvalue(func);
+    L->top--;  /* pop function */
+  }
+  else if (ar->i_ci != 0) {  /* no tail call? */
+    ci = L->base_ci + ar->i_ci;
+    lua_assert(ttisfunction(ci->func));
+    f = clvalue(ci->func);
+  }
+  status = auxgetinfo(L, what, ar, f, ci);
+  if (strchr(what, 'f')) {
+    if (f == NULL) setnilvalue(L->top);
+    else setclvalue(L, L->top, f);
+    incr_top(L);
+  }
+  if (strchr(what, 'L'))
+    collectvalidlines(L, f);
+  lua_unlock(L);
+  return status;
+}
+
+
+/*
+** {======================================================
+** Symbolic Execution and code checker
+** =======================================================
+*/
+
+#define check(x)		if (!(x)) return 0;
+
+#define checkjump(pt,pc)	check(0 <= pc && pc < pt->sizecode)
+
+#define checkreg(pt,reg)	check((reg) < (pt)->maxstacksize)
+
+
+
+static int precheck (const Proto *pt) {
+  check(pt->maxstacksize <= MAXSTACK);
+  lua_assert(pt->numparams+(pt->is_vararg & VARARG_HASARG) <= pt->maxstacksize);
+  lua_assert(!(pt->is_vararg & VARARG_NEEDSARG) ||
+              (pt->is_vararg & VARARG_HASARG));
+  check(pt->sizeupvalues <= pt->nups);
+  check(pt->sizelineinfo == pt->sizecode || pt->sizelineinfo == 0);
+  check(GET_OPCODE(pt->code[pt->sizecode-1]) == OP_RETURN);
+  return 1;
+}
+
+
+#define checkopenop(pt,pc)	luaG_checkopenop((pt)->code[(pc)+1])
+
+int luaG_checkopenop (Instruction i) {
+  switch (GET_OPCODE(i)) {
+    case OP_CALL:
+    case OP_TAILCALL:
+    case OP_RETURN:
+    case OP_SETLIST: {
+      check(GETARG_B(i) == 0);
+      return 1;
+    }
+    default: return 0;  /* invalid instruction after an open call */
+  }
+}
+
+
+static int checkArgMode (const Proto *pt, int r, enum OpArgMask mode) {
+  switch (mode) {
+    case OpArgN: check(r == 0); break;
+    case OpArgU: break;
+    case OpArgR: checkreg(pt, r); break;
+    case OpArgK:
+      check(ISK(r) ? INDEXK(r) < pt->sizek : r < pt->maxstacksize);
+      break;
+  }
+  return 1;
+}
+
+
+static Instruction symbexec (const Proto *pt, int lastpc, int reg) {
+  int pc;
+  int last;  /* stores position of last instruction that changed `reg' */
+  last = pt->sizecode-1;  /* points to final return (a `neutral' instruction) */
+  check(precheck(pt));
+  for (pc = 0; pc < lastpc; pc++) {
+    Instruction i = pt->code[pc];
+    OpCode op = GET_OPCODE(i);
+    int a = GETARG_A(i);
+    int b = 0;
+    int c = 0;
+    check(op < NUM_OPCODES);
+    checkreg(pt, a);
+    switch (getOpMode(op)) {
+      case iABC: {
+        b = GETARG_B(i);
+        c = GETARG_C(i);
+        check(checkArgMode(pt, b, getBMode(op)));
+        check(checkArgMode(pt, c, getCMode(op)));
+        break;
+      }
+      case iABx: {
+        b = GETARG_Bx(i);
+        if (getBMode(op) == OpArgK) check(b < pt->sizek);
+        break;
+      }
+      case iAsBx: {
+        b = GETARG_sBx(i);
+        if (getBMode(op) == OpArgR) {
+          int dest = pc+1+b;
+          check(0 <= dest && dest < pt->sizecode);
+          if (dest > 0) {
+            /* cannot jump to a setlist count */
+            Instruction d = pt->code[dest-1];
+            check(!(GET_OPCODE(d) == OP_SETLIST && GETARG_C(d) == 0));
+          }
+        }
+        break;
+      }
+    }
+    if (testAMode(op)) {
+      if (a == reg) last = pc;  /* change register `a' */
+    }
+    if (testTMode(op)) {
+      check(pc+2 < pt->sizecode);  /* check skip */
+      check(GET_OPCODE(pt->code[pc+1]) == OP_JMP);
+    }
+    switch (op) {
+      case OP_LOADBOOL: {
+        check(c == 0 || pc+2 < pt->sizecode);  /* check its jump */
+        break;
+      }
+      case OP_LOADNIL: {
+        if (a <= reg && reg <= b)
+          last = pc;  /* set registers from `a' to `b' */
+        break;
+      }
+      case OP_GETUPVAL:
+      case OP_SETUPVAL: {
+        check(b < pt->nups);
+        break;
+      }
+      case OP_GETGLOBAL:
+      case OP_SETGLOBAL: {
+        check(ttisstring(&pt->k[b]));
+        break;
+      }
+      case OP_SELF: {
+        checkreg(pt, a+1);
+        if (reg == a+1) last = pc;
+        break;
+      }
+      case OP_CONCAT: {
+        check(b < c);  /* at least two operands */
+        break;
+      }
+      case OP_TFORLOOP: {
+        check(c >= 1);  /* at least one result (control variable) */
+        checkreg(pt, a+2+c);  /* space for results */
+        if (reg >= a+2) last = pc;  /* affect all regs above its base */
+        break;
+      }
+      case OP_FORLOOP:
+      case OP_FORPREP:
+        checkreg(pt, a+3);
+        /* go through */
+      case OP_JMP: {
+        int dest = pc+1+b;
+        /* not full check and jump is forward and do not skip `lastpc'? */
+        if (reg != NO_REG && pc < dest && dest <= lastpc)
+          pc += b;  /* do the jump */
+        break;
+      }
+      case OP_CALL:
+      case OP_TAILCALL: {
+        if (b != 0) {
+          checkreg(pt, a+b-1);
+        }
+        c--;  /* c = num. returns */
+        if (c == LUA_MULTRET) {
+          check(checkopenop(pt, pc));
+        }
+        else if (c != 0)
+          checkreg(pt, a+c-1);
+        if (reg >= a) last = pc;  /* affect all registers above base */
+        break;
+      }
+      case OP_RETURN: {
+        b--;  /* b = num. returns */
+        if (b > 0) checkreg(pt, a+b-1);
+        break;
+      }
+      case OP_SETLIST: {
+        if (b > 0) checkreg(pt, a + b);
+        if (c == 0) pc++;
+        break;
+      }
+      case OP_CLOSURE: {
+        int nup, j;
+        check(b < pt->sizep);
+        nup = pt->p[b]->nups;
+        check(pc + nup < pt->sizecode);
+        for (j = 1; j <= nup; j++) {
+          OpCode op1 = GET_OPCODE(pt->code[pc + j]);
+          check(op1 == OP_GETUPVAL || op1 == OP_MOVE);
+        }
+        if (reg != NO_REG)  /* tracing? */
+          pc += nup;  /* do not 'execute' these pseudo-instructions */
+        break;
+      }
+      case OP_VARARG: {
+        check((pt->is_vararg & VARARG_ISVARARG) &&
+             !(pt->is_vararg & VARARG_NEEDSARG));
+        b--;
+        if (b == LUA_MULTRET) check(checkopenop(pt, pc));
+        checkreg(pt, a+b-1);
+        break;
+      }
+      default: break;
+    }
+  }
+  return pt->code[last];
+}
+
+#undef check
+#undef checkjump
+#undef checkreg
+
+/* }====================================================== */
+
+
+int luaG_checkcode (const Proto *pt) {
+  return (symbexec(pt, pt->sizecode, NO_REG) != 0);
+}
+
+
+static const char *kname (Proto *p, int c) {
+  if (ISK(c) && ttisstring(&p->k[INDEXK(c)]))
+    return svalue(&p->k[INDEXK(c)]);
+  else
+    return "?";
+}
+
+
+static const char *getobjname (lua_State *L, CallInfo *ci, int stackpos,
+                               const char **name) {
+  if (isLua(ci)) {  /* a Lua function? */
+    Proto *p = ci_func(ci)->l.p;
+    int pc = currentpc(L, ci);
+    Instruction i;
+    *name = luaF_getlocalname(p, stackpos+1, pc);
+    if (*name)  /* is a local? */
+      return "local";
+    i = symbexec(p, pc, stackpos);  /* try symbolic execution */
+    lua_assert(pc != -1);
+    switch (GET_OPCODE(i)) {
+      case OP_GETGLOBAL: {
+        int g = GETARG_Bx(i);  /* global index */
+        lua_assert(ttisstring(&p->k[g]));
+        *name = svalue(&p->k[g]);
+        return "global";
+      }
+      case OP_MOVE: {
+        int a = GETARG_A(i);
+        int b = GETARG_B(i);  /* move from `b' to `a' */
+        if (b < a)
+          return getobjname(L, ci, b, name);  /* get name for `b' */
+        break;
+      }
+      case OP_GETTABLE: {
+        int k = GETARG_C(i);  /* key index */
+        *name = kname(p, k);
+        return "field";
+      }
+      case OP_GETUPVAL: {
+        int u = GETARG_B(i);  /* upvalue index */
+        *name = p->upvalues ? getstr(p->upvalues[u]) : "?";
+        return "upvalue";
+      }
+      case OP_SELF: {
+        int k = GETARG_C(i);  /* key index */
+        *name = kname(p, k);
+        return "method";
+      }
+      default: break;
+    }
+  }
+  return NULL;  /* no useful name found */
+}
+
+
+static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name) {
+  Instruction i;
+  if ((isLua(ci) && ci->tailcalls > 0) || !isLua(ci - 1))
+    return NULL;  /* calling function is not Lua (or is unknown) */
+  ci--;  /* calling function */
+  i = ci_func(ci)->l.p->code[currentpc(L, ci)];
+  if (GET_OPCODE(i) == OP_CALL || GET_OPCODE(i) == OP_TAILCALL ||
+      GET_OPCODE(i) == OP_TFORLOOP)
+    return getobjname(L, ci, GETARG_A(i), name);
+  else
+    return NULL;  /* no useful name can be found */
+}
+
+
+/* only ANSI way to check whether a pointer points to an array */
+static int isinstack (CallInfo *ci, const TValue *o) {
+  StkId p;
+  for (p = ci->base; p < ci->top; p++)
+    if (o == p) return 1;
+  return 0;
+}
+
+
+void luaG_typeerror (lua_State *L, const TValue *o, const char *op) {
+  const char *name = NULL;
+  const char *t = luaT_typenames[ttype(o)];
+  const char *kind = (isinstack(L->ci, o)) ?
+                         getobjname(L, L->ci, cast_int(o - L->base), &name) :
+                         NULL;
+  if (kind)
+    luaG_runerror(L, "attempt to %s %s " LUA_QS " (a %s value)",
+                op, kind, name, t);
+  else
+    luaG_runerror(L, "attempt to %s a %s value", op, t);
+}
+
+
+void luaG_concaterror (lua_State *L, StkId p1, StkId p2) {
+  if (ttisstring(p1) || ttisnumber(p1)) p1 = p2;
+  lua_assert(!ttisstring(p1) && !ttisnumber(p1));
+  luaG_typeerror(L, p1, "concatenate");
+}
+
+
+void luaG_aritherror (lua_State *L, const TValue *p1, const TValue *p2) {
+  TValue temp;
+  if (luaV_tonumber(p1, &temp) == NULL)
+    p2 = p1;  /* first operand is wrong */
+  luaG_typeerror(L, p2, "perform arithmetic on");
+}
+
+
+int luaG_ordererror (lua_State *L, const TValue *p1, const TValue *p2) {
+  const char *t1 = luaT_typenames[ttype(p1)];
+  const char *t2 = luaT_typenames[ttype(p2)];
+  if (t1[2] == t2[2])
+    luaG_runerror(L, "attempt to compare two %s values", t1);
+  else
+    luaG_runerror(L, "attempt to compare %s with %s", t1, t2);
+  return 0;
+}
+
+
+static void addinfo (lua_State *L, const char *msg) {
+  CallInfo *ci = L->ci;
+  if (isLua(ci)) {  /* is Lua code? */
+    char buff[LUA_IDSIZE];  /* add file:line information */
+    int line = currentline(L, ci);
+    luaO_chunkid(buff, getstr(getluaproto(ci)->source), LUA_IDSIZE);
+    luaO_pushfstring(L, "%s:%d: %s", buff, line, msg);
+  }
+}
+
+
+void luaG_errormsg (lua_State *L) {
+  if (L->errfunc != 0) {  /* is there an error handling function? */
+    StkId errfunc = restorestack(L, L->errfunc);
+    if (!ttisfunction(errfunc)) luaD_throw(L, LUA_ERRERR);
+    setobjs2s(L, L->top, L->top - 1);  /* move argument */
+    setobjs2s(L, L->top - 1, errfunc);  /* push function */
+    incr_top(L);
+    luaD_call(L, L->top - 2, 1);  /* call it */
+  }
+  luaD_throw(L, LUA_ERRRUN);
+}
+
+
+void luaG_runerror (lua_State *L, const char *fmt, ...) {
+  va_list argp;
+  va_start(argp, fmt);
+  addinfo(L, luaO_pushvfstring(L, fmt, argp));
+  va_end(argp);
+  luaG_errormsg(L);
+}
+
diff --git a/com32/lua/src/ldebug.h b/com32/lua/src/ldebug.h
new file mode 100644
index 00000000..ba28a972
--- /dev/null
+++ b/com32/lua/src/ldebug.h
@@ -0,0 +1,33 @@
+/*
+** $Id: ldebug.h,v 2.3.1.1 2007/12/27 13:02:25 roberto Exp $
+** Auxiliary functions from Debug Interface module
+** See Copyright Notice in lua.h
+*/
+
+#ifndef ldebug_h
+#define ldebug_h
+
+
+#include "lstate.h"
+
+
+#define pcRel(pc, p)	(cast(int, (pc) - (p)->code) - 1)
+
+#define getline(f,pc)	(((f)->lineinfo) ? (f)->lineinfo[pc] : 0)
+
+#define resethookcount(L)	(L->hookcount = L->basehookcount)
+
+
+LUAI_FUNC void luaG_typeerror (lua_State *L, const TValue *o,
+                                             const char *opname);
+LUAI_FUNC void luaG_concaterror (lua_State *L, StkId p1, StkId p2);
+LUAI_FUNC void luaG_aritherror (lua_State *L, const TValue *p1,
+                                              const TValue *p2);
+LUAI_FUNC int luaG_ordererror (lua_State *L, const TValue *p1,
+                                             const TValue *p2);
+LUAI_FUNC void luaG_runerror (lua_State *L, const char *fmt, ...);
+LUAI_FUNC void luaG_errormsg (lua_State *L);
+LUAI_FUNC int luaG_checkcode (const Proto *pt);
+LUAI_FUNC int luaG_checkopenop (Instruction i);
+
+#endif
diff --git a/com32/lua/src/ldo.c b/com32/lua/src/ldo.c
new file mode 100644
index 00000000..8de05f72
--- /dev/null
+++ b/com32/lua/src/ldo.c
@@ -0,0 +1,518 @@
+/*
+** $Id: ldo.c,v 2.38.1.3 2008/01/18 22:31:22 roberto Exp $
+** Stack and Call structure of Lua
+** See Copyright Notice in lua.h
+*/
+
+
+#include <setjmp.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define ldo_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lopcodes.h"
+#include "lparser.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+#include "lundump.h"
+#include "lvm.h"
+#include "lzio.h"
+
+
+
+
+/*
+** {======================================================
+** Error-recovery functions
+** =======================================================
+*/
+
+
+/* chain list of long jump buffers */
+struct lua_longjmp {
+  struct lua_longjmp *previous;
+  luai_jmpbuf b;
+  volatile int status;  /* error code */
+};
+
+
+void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop) {
+  switch (errcode) {
+    case LUA_ERRMEM: {
+      setsvalue2s(L, oldtop, luaS_newliteral(L, MEMERRMSG));
+      break;
+    }
+    case LUA_ERRERR: {
+      setsvalue2s(L, oldtop, luaS_newliteral(L, "error in error handling"));
+      break;
+    }
+    case LUA_ERRSYNTAX:
+    case LUA_ERRRUN: {
+      setobjs2s(L, oldtop, L->top - 1);  /* error message on current top */
+      break;
+    }
+  }
+  L->top = oldtop + 1;
+}
+
+
+static void restore_stack_limit (lua_State *L) {
+  lua_assert(L->stack_last - L->stack == L->stacksize - EXTRA_STACK - 1);
+  if (L->size_ci > LUAI_MAXCALLS) {  /* there was an overflow? */
+    int inuse = cast_int(L->ci - L->base_ci);
+    if (inuse + 1 < LUAI_MAXCALLS)  /* can `undo' overflow? */
+      luaD_reallocCI(L, LUAI_MAXCALLS);
+  }
+}
+
+
+static void resetstack (lua_State *L, int status) {
+  L->ci = L->base_ci;
+  L->base = L->ci->base;
+  luaF_close(L, L->base);  /* close eventual pending closures */
+  luaD_seterrorobj(L, status, L->base);
+  L->nCcalls = L->baseCcalls;
+  L->allowhook = 1;
+  restore_stack_limit(L);
+  L->errfunc = 0;
+  L->errorJmp = NULL;
+}
+
+
+void luaD_throw (lua_State *L, int errcode) {
+  if (L->errorJmp) {
+    L->errorJmp->status = errcode;
+    LUAI_THROW(L, L->errorJmp);
+  }
+  else {
+    L->status = cast_byte(errcode);
+    if (G(L)->panic) {
+      resetstack(L, errcode);
+      lua_unlock(L);
+      G(L)->panic(L);
+    }
+    exit(EXIT_FAILURE);
+  }
+}
+
+
+int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud) {
+  struct lua_longjmp lj;
+  lj.status = 0;
+  lj.previous = L->errorJmp;  /* chain new error handler */
+  L->errorJmp = &lj;
+  LUAI_TRY(L, &lj,
+    (*f)(L, ud);
+  );
+  L->errorJmp = lj.previous;  /* restore old error handler */
+  return lj.status;
+}
+
+/* }====================================================== */
+
+
+static void correctstack (lua_State *L, TValue *oldstack) {
+  CallInfo *ci;
+  GCObject *up;
+  L->top = (L->top - oldstack) + L->stack;
+  for (up = L->openupval; up != NULL; up = up->gch.next)
+    gco2uv(up)->v = (gco2uv(up)->v - oldstack) + L->stack;
+  for (ci = L->base_ci; ci <= L->ci; ci++) {
+    ci->top = (ci->top - oldstack) + L->stack;
+    ci->base = (ci->base - oldstack) + L->stack;
+    ci->func = (ci->func - oldstack) + L->stack;
+  }
+  L->base = (L->base - oldstack) + L->stack;
+}
+
+
+void luaD_reallocstack (lua_State *L, int newsize) {
+  TValue *oldstack = L->stack;
+  int realsize = newsize + 1 + EXTRA_STACK;
+  lua_assert(L->stack_last - L->stack == L->stacksize - EXTRA_STACK - 1);
+  luaM_reallocvector(L, L->stack, L->stacksize, realsize, TValue);
+  L->stacksize = realsize;
+  L->stack_last = L->stack+newsize;
+  correctstack(L, oldstack);
+}
+
+
+void luaD_reallocCI (lua_State *L, int newsize) {
+  CallInfo *oldci = L->base_ci;
+  luaM_reallocvector(L, L->base_ci, L->size_ci, newsize, CallInfo);
+  L->size_ci = newsize;
+  L->ci = (L->ci - oldci) + L->base_ci;
+  L->end_ci = L->base_ci + L->size_ci - 1;
+}
+
+
+void luaD_growstack (lua_State *L, int n) {
+  if (n <= L->stacksize)  /* double size is enough? */
+    luaD_reallocstack(L, 2*L->stacksize);
+  else
+    luaD_reallocstack(L, L->stacksize + n);
+}
+
+
+static CallInfo *growCI (lua_State *L) {
+  if (L->size_ci > LUAI_MAXCALLS)  /* overflow while handling overflow? */
+    luaD_throw(L, LUA_ERRERR);
+  else {
+    luaD_reallocCI(L, 2*L->size_ci);
+    if (L->size_ci > LUAI_MAXCALLS)
+      luaG_runerror(L, "stack overflow");
+  }
+  return ++L->ci;
+}
+
+
+void luaD_callhook (lua_State *L, int event, int line) {
+  lua_Hook hook = L->hook;
+  if (hook && L->allowhook) {
+    ptrdiff_t top = savestack(L, L->top);
+    ptrdiff_t ci_top = savestack(L, L->ci->top);
+    lua_Debug ar;
+    ar.event = event;
+    ar.currentline = line;
+    if (event == LUA_HOOKTAILRET)
+      ar.i_ci = 0;  /* tail call; no debug information about it */
+    else
+      ar.i_ci = cast_int(L->ci - L->base_ci);
+    luaD_checkstack(L, LUA_MINSTACK);  /* ensure minimum stack size */
+    L->ci->top = L->top + LUA_MINSTACK;
+    lua_assert(L->ci->top <= L->stack_last);
+    L->allowhook = 0;  /* cannot call hooks inside a hook */
+    lua_unlock(L);
+    (*hook)(L, &ar);
+    lua_lock(L);
+    lua_assert(!L->allowhook);
+    L->allowhook = 1;
+    L->ci->top = restorestack(L, ci_top);
+    L->top = restorestack(L, top);
+  }
+}
+
+
+static StkId adjust_varargs (lua_State *L, Proto *p, int actual) {
+  int i;
+  int nfixargs = p->numparams;
+  Table *htab = NULL;
+  StkId base, fixed;
+  for (; actual < nfixargs; ++actual)
+    setnilvalue(L->top++);
+#if defined(LUA_COMPAT_VARARG)
+  if (p->is_vararg & VARARG_NEEDSARG) { /* compat. with old-style vararg? */
+    int nvar = actual - nfixargs;  /* number of extra arguments */
+    lua_assert(p->is_vararg & VARARG_HASARG);
+    luaC_checkGC(L);
+    htab = luaH_new(L, nvar, 1);  /* create `arg' table */
+    for (i=0; i<nvar; i++)  /* put extra arguments into `arg' table */
+      setobj2n(L, luaH_setnum(L, htab, i+1), L->top - nvar + i);
+    /* store counter in field `n' */
+    setnvalue(luaH_setstr(L, htab, luaS_newliteral(L, "n")), cast_num(nvar));
+  }
+#endif
+  /* move fixed parameters to final position */
+  fixed = L->top - actual;  /* first fixed argument */
+  base = L->top;  /* final position of first argument */
+  for (i=0; i<nfixargs; i++) {
+    setobjs2s(L, L->top++, fixed+i);
+    setnilvalue(fixed+i);
+  }
+  /* add `arg' parameter */
+  if (htab) {
+    sethvalue(L, L->top++, htab);
+    lua_assert(iswhite(obj2gco(htab)));
+  }
+  return base;
+}
+
+
+static StkId tryfuncTM (lua_State *L, StkId func) {
+  const TValue *tm = luaT_gettmbyobj(L, func, TM_CALL);
+  StkId p;
+  ptrdiff_t funcr = savestack(L, func);
+  if (!ttisfunction(tm))
+    luaG_typeerror(L, func, "call");
+  /* Open a hole inside the stack at `func' */
+  for (p = L->top; p > func; p--) setobjs2s(L, p, p-1);
+  incr_top(L);
+  func = restorestack(L, funcr);  /* previous call may change stack */
+  setobj2s(L, func, tm);  /* tag method is the new function to be called */
+  return func;
+}
+
+
+
+#define inc_ci(L) \
+  ((L->ci == L->end_ci) ? growCI(L) : \
+   (condhardstacktests(luaD_reallocCI(L, L->size_ci)), ++L->ci))
+
+
+int luaD_precall (lua_State *L, StkId func, int nresults) {
+  LClosure *cl;
+  ptrdiff_t funcr;
+  if (!ttisfunction(func)) /* `func' is not a function? */
+    func = tryfuncTM(L, func);  /* check the `function' tag method */
+  funcr = savestack(L, func);
+  cl = &clvalue(func)->l;
+  L->ci->savedpc = L->savedpc;
+  if (!cl->isC) {  /* Lua function? prepare its call */
+    CallInfo *ci;
+    StkId st, base;
+    Proto *p = cl->p;
+    luaD_checkstack(L, p->maxstacksize);
+    func = restorestack(L, funcr);
+    if (!p->is_vararg) {  /* no varargs? */
+      base = func + 1;
+      if (L->top > base + p->numparams)
+        L->top = base + p->numparams;
+    }
+    else {  /* vararg function */
+      int nargs = cast_int(L->top - func) - 1;
+      base = adjust_varargs(L, p, nargs);
+      func = restorestack(L, funcr);  /* previous call may change the stack */
+    }
+    ci = inc_ci(L);  /* now `enter' new function */
+    ci->func = func;
+    L->base = ci->base = base;
+    ci->top = L->base + p->maxstacksize;
+    lua_assert(ci->top <= L->stack_last);
+    L->savedpc = p->code;  /* starting point */
+    ci->tailcalls = 0;
+    ci->nresults = nresults;
+    for (st = L->top; st < ci->top; st++)
+      setnilvalue(st);
+    L->top = ci->top;
+    if (L->hookmask & LUA_MASKCALL) {
+      L->savedpc++;  /* hooks assume 'pc' is already incremented */
+      luaD_callhook(L, LUA_HOOKCALL, -1);
+      L->savedpc--;  /* correct 'pc' */
+    }
+    return PCRLUA;
+  }
+  else {  /* if is a C function, call it */
+    CallInfo *ci;
+    int n;
+    luaD_checkstack(L, LUA_MINSTACK);  /* ensure minimum stack size */
+    ci = inc_ci(L);  /* now `enter' new function */
+    ci->func = restorestack(L, funcr);
+    L->base = ci->base = ci->func + 1;
+    ci->top = L->top + LUA_MINSTACK;
+    lua_assert(ci->top <= L->stack_last);
+    ci->nresults = nresults;
+    if (L->hookmask & LUA_MASKCALL)
+      luaD_callhook(L, LUA_HOOKCALL, -1);
+    lua_unlock(L);
+    n = (*curr_func(L)->c.f)(L);  /* do the actual call */
+    lua_lock(L);
+    if (n < 0)  /* yielding? */
+      return PCRYIELD;
+    else {
+      luaD_poscall(L, L->top - n);
+      return PCRC;
+    }
+  }
+}
+
+
+static StkId callrethooks (lua_State *L, StkId firstResult) {
+  ptrdiff_t fr = savestack(L, firstResult);  /* next call may change stack */
+  luaD_callhook(L, LUA_HOOKRET, -1);
+  if (f_isLua(L->ci)) {  /* Lua function? */
+    while ((L->hookmask & LUA_MASKRET) && L->ci->tailcalls--) /* tail calls */
+      luaD_callhook(L, LUA_HOOKTAILRET, -1);
+  }
+  return restorestack(L, fr);
+}
+
+
+int luaD_poscall (lua_State *L, StkId firstResult) {
+  StkId res;
+  int wanted, i;
+  CallInfo *ci;
+  if (L->hookmask & LUA_MASKRET)
+    firstResult = callrethooks(L, firstResult);
+  ci = L->ci--;
+  res = ci->func;  /* res == final position of 1st result */
+  wanted = ci->nresults;
+  L->base = (ci - 1)->base;  /* restore base */
+  L->savedpc = (ci - 1)->savedpc;  /* restore savedpc */
+  /* move results to correct place */
+  for (i = wanted; i != 0 && firstResult < L->top; i--)
+    setobjs2s(L, res++, firstResult++);
+  while (i-- > 0)
+    setnilvalue(res++);
+  L->top = res;
+  return (wanted - LUA_MULTRET);  /* 0 iff wanted == LUA_MULTRET */
+}
+
+
+/*
+** Call a function (C or Lua). The function to be called is at *func.
+** The arguments are on the stack, right after the function.
+** When returns, all the results are on the stack, starting at the original
+** function position.
+*/ 
+void luaD_call (lua_State *L, StkId func, int nResults) {
+  if (++L->nCcalls >= LUAI_MAXCCALLS) {
+    if (L->nCcalls == LUAI_MAXCCALLS)
+      luaG_runerror(L, "C stack overflow");
+    else if (L->nCcalls >= (LUAI_MAXCCALLS + (LUAI_MAXCCALLS>>3)))
+      luaD_throw(L, LUA_ERRERR);  /* error while handing stack error */
+  }
+  if (luaD_precall(L, func, nResults) == PCRLUA)  /* is a Lua function? */
+    luaV_execute(L, 1);  /* call it */
+  L->nCcalls--;
+  luaC_checkGC(L);
+}
+
+
+static void resume (lua_State *L, void *ud) {
+  StkId firstArg = cast(StkId, ud);
+  CallInfo *ci = L->ci;
+  if (L->status == 0) {  /* start coroutine? */
+    lua_assert(ci == L->base_ci && firstArg > L->base);
+    if (luaD_precall(L, firstArg - 1, LUA_MULTRET) != PCRLUA)
+      return;
+  }
+  else {  /* resuming from previous yield */
+    lua_assert(L->status == LUA_YIELD);
+    L->status = 0;
+    if (!f_isLua(ci)) {  /* `common' yield? */
+      /* finish interrupted execution of `OP_CALL' */
+      lua_assert(GET_OPCODE(*((ci-1)->savedpc - 1)) == OP_CALL ||
+                 GET_OPCODE(*((ci-1)->savedpc - 1)) == OP_TAILCALL);
+      if (luaD_poscall(L, firstArg))  /* complete it... */
+        L->top = L->ci->top;  /* and correct top if not multiple results */
+    }
+    else  /* yielded inside a hook: just continue its execution */
+      L->base = L->ci->base;
+  }
+  luaV_execute(L, cast_int(L->ci - L->base_ci));
+}
+
+
+static int resume_error (lua_State *L, const char *msg) {
+  L->top = L->ci->base;
+  setsvalue2s(L, L->top, luaS_new(L, msg));
+  incr_top(L);
+  lua_unlock(L);
+  return LUA_ERRRUN;
+}
+
+
+LUA_API int lua_resume (lua_State *L, int nargs) {
+  int status;
+  lua_lock(L);
+  if (L->status != LUA_YIELD && (L->status != 0 || L->ci != L->base_ci))
+      return resume_error(L, "cannot resume non-suspended coroutine");
+  if (L->nCcalls >= LUAI_MAXCCALLS)
+    return resume_error(L, "C stack overflow");
+  luai_userstateresume(L, nargs);
+  lua_assert(L->errfunc == 0);
+  L->baseCcalls = ++L->nCcalls;
+  status = luaD_rawrunprotected(L, resume, L->top - nargs);
+  if (status != 0) {  /* error? */
+    L->status = cast_byte(status);  /* mark thread as `dead' */
+    luaD_seterrorobj(L, status, L->top);
+    L->ci->top = L->top;
+  }
+  else {
+    lua_assert(L->nCcalls == L->baseCcalls);
+    status = L->status;
+  }
+  --L->nCcalls;
+  lua_unlock(L);
+  return status;
+}
+
+
+LUA_API int lua_yield (lua_State *L, int nresults) {
+  luai_userstateyield(L, nresults);
+  lua_lock(L);
+  if (L->nCcalls > L->baseCcalls)
+    luaG_runerror(L, "attempt to yield across metamethod/C-call boundary");
+  L->base = L->top - nresults;  /* protect stack slots below */
+  L->status = LUA_YIELD;
+  lua_unlock(L);
+  return -1;
+}
+
+
+int luaD_pcall (lua_State *L, Pfunc func, void *u,
+                ptrdiff_t old_top, ptrdiff_t ef) {
+  int status;
+  unsigned short oldnCcalls = L->nCcalls;
+  ptrdiff_t old_ci = saveci(L, L->ci);
+  lu_byte old_allowhooks = L->allowhook;
+  ptrdiff_t old_errfunc = L->errfunc;
+  L->errfunc = ef;
+  status = luaD_rawrunprotected(L, func, u);
+  if (status != 0) {  /* an error occurred? */
+    StkId oldtop = restorestack(L, old_top);
+    luaF_close(L, oldtop);  /* close eventual pending closures */
+    luaD_seterrorobj(L, status, oldtop);
+    L->nCcalls = oldnCcalls;
+    L->ci = restoreci(L, old_ci);
+    L->base = L->ci->base;
+    L->savedpc = L->ci->savedpc;
+    L->allowhook = old_allowhooks;
+    restore_stack_limit(L);
+  }
+  L->errfunc = old_errfunc;
+  return status;
+}
+
+
+
+/*
+** Execute a protected parser.
+*/
+struct SParser {  /* data to `f_parser' */
+  ZIO *z;
+  Mbuffer buff;  /* buffer to be used by the scanner */
+  const char *name;
+};
+
+static void f_parser (lua_State *L, void *ud) {
+  int i;
+  Proto *tf;
+  Closure *cl;
+  struct SParser *p = cast(struct SParser *, ud);
+  int c = luaZ_lookahead(p->z);
+  luaC_checkGC(L);
+  tf = ((c == LUA_SIGNATURE[0]) ? luaU_undump : luaY_parser)(L, p->z,
+                                                             &p->buff, p->name);
+  cl = luaF_newLclosure(L, tf->nups, hvalue(gt(L)));
+  cl->l.p = tf;
+  for (i = 0; i < tf->nups; i++)  /* initialize eventual upvalues */
+    cl->l.upvals[i] = luaF_newupval(L);
+  setclvalue(L, L->top, cl);
+  incr_top(L);
+}
+
+
+int luaD_protectedparser (lua_State *L, ZIO *z, const char *name) {
+  struct SParser p;
+  int status;
+  p.z = z; p.name = name;
+  luaZ_initbuffer(L, &p.buff);
+  status = luaD_pcall(L, f_parser, &p, savestack(L, L->top), L->errfunc);
+  luaZ_freebuffer(L, &p.buff);
+  return status;
+}
+
+
diff --git a/com32/lua/src/ldo.h b/com32/lua/src/ldo.h
new file mode 100644
index 00000000..98fddac5
--- /dev/null
+++ b/com32/lua/src/ldo.h
@@ -0,0 +1,57 @@
+/*
+** $Id: ldo.h,v 2.7.1.1 2007/12/27 13:02:25 roberto Exp $
+** Stack and Call structure of Lua
+** See Copyright Notice in lua.h
+*/
+
+#ifndef ldo_h
+#define ldo_h
+
+
+#include "lobject.h"
+#include "lstate.h"
+#include "lzio.h"
+
+
+#define luaD_checkstack(L,n)	\
+  if ((char *)L->stack_last - (char *)L->top <= (n)*(int)sizeof(TValue)) \
+    luaD_growstack(L, n); \
+  else condhardstacktests(luaD_reallocstack(L, L->stacksize - EXTRA_STACK - 1));
+
+
+#define incr_top(L) {luaD_checkstack(L,1); L->top++;}
+
+#define savestack(L,p)		((char *)(p) - (char *)L->stack)
+#define restorestack(L,n)	((TValue *)((char *)L->stack + (n)))
+
+#define saveci(L,p)		((char *)(p) - (char *)L->base_ci)
+#define restoreci(L,n)		((CallInfo *)((char *)L->base_ci + (n)))
+
+
+/* results from luaD_precall */
+#define PCRLUA		0	/* initiated a call to a Lua function */
+#define PCRC		1	/* did a call to a C function */
+#define PCRYIELD	2	/* C funtion yielded */
+
+
+/* type of protected functions, to be ran by `runprotected' */
+typedef void (*Pfunc) (lua_State *L, void *ud);
+
+LUAI_FUNC int luaD_protectedparser (lua_State *L, ZIO *z, const char *name);
+LUAI_FUNC void luaD_callhook (lua_State *L, int event, int line);
+LUAI_FUNC int luaD_precall (lua_State *L, StkId func, int nresults);
+LUAI_FUNC void luaD_call (lua_State *L, StkId func, int nResults);
+LUAI_FUNC int luaD_pcall (lua_State *L, Pfunc func, void *u,
+                                        ptrdiff_t oldtop, ptrdiff_t ef);
+LUAI_FUNC int luaD_poscall (lua_State *L, StkId firstResult);
+LUAI_FUNC void luaD_reallocCI (lua_State *L, int newsize);
+LUAI_FUNC void luaD_reallocstack (lua_State *L, int newsize);
+LUAI_FUNC void luaD_growstack (lua_State *L, int n);
+
+LUAI_FUNC void luaD_throw (lua_State *L, int errcode);
+LUAI_FUNC int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud);
+
+LUAI_FUNC void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop);
+
+#endif
+
diff --git a/com32/lua/src/ldump.c b/com32/lua/src/ldump.c
new file mode 100644
index 00000000..c9d3d487
--- /dev/null
+++ b/com32/lua/src/ldump.c
@@ -0,0 +1,164 @@
+/*
+** $Id: ldump.c,v 2.8.1.1 2007/12/27 13:02:25 roberto Exp $
+** save precompiled Lua chunks
+** See Copyright Notice in lua.h
+*/
+
+#include <stddef.h>
+
+#define ldump_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "lobject.h"
+#include "lstate.h"
+#include "lundump.h"
+
+typedef struct {
+ lua_State* L;
+ lua_Writer writer;
+ void* data;
+ int strip;
+ int status;
+} DumpState;
+
+#define DumpMem(b,n,size,D)	DumpBlock(b,(n)*(size),D)
+#define DumpVar(x,D)	 	DumpMem(&x,1,sizeof(x),D)
+
+static void DumpBlock(const void* b, size_t size, DumpState* D)
+{
+ if (D->status==0)
+ {
+  lua_unlock(D->L);
+  D->status=(*D->writer)(D->L,b,size,D->data);
+  lua_lock(D->L);
+ }
+}
+
+static void DumpChar(int y, DumpState* D)
+{
+ char x=(char)y;
+ DumpVar(x,D);
+}
+
+static void DumpInt(int x, DumpState* D)
+{
+ DumpVar(x,D);
+}
+
+static void DumpNumber(lua_Number x, DumpState* D)
+{
+ DumpVar(x,D);
+}
+
+static void DumpVector(const void* b, int n, size_t size, DumpState* D)
+{
+ DumpInt(n,D);
+ DumpMem(b,n,size,D);
+}
+
+static void DumpString(const TString* s, DumpState* D)
+{
+ if (s==NULL || getstr(s)==NULL)
+ {
+  size_t size=0;
+  DumpVar(size,D);
+ }
+ else
+ {
+  size_t size=s->tsv.len+1;		/* include trailing '\0' */
+  DumpVar(size,D);
+  DumpBlock(getstr(s),size,D);
+ }
+}
+
+#define DumpCode(f,D)	 DumpVector(f->code,f->sizecode,sizeof(Instruction),D)
+
+static void DumpFunction(const Proto* f, const TString* p, DumpState* D);
+
+static void DumpConstants(const Proto* f, DumpState* D)
+{
+ int i,n=f->sizek;
+ DumpInt(n,D);
+ for (i=0; i<n; i++)
+ {
+  const TValue* o=&f->k[i];
+  DumpChar(ttype(o),D);
+  switch (ttype(o))
+  {
+   case LUA_TNIL:
+	break;
+   case LUA_TBOOLEAN:
+	DumpChar(bvalue(o),D);
+	break;
+   case LUA_TNUMBER:
+	DumpNumber(nvalue(o),D);
+	break;
+   case LUA_TSTRING:
+	DumpString(rawtsvalue(o),D);
+	break;
+   default:
+	lua_assert(0);			/* cannot happen */
+	break;
+  }
+ }
+ n=f->sizep;
+ DumpInt(n,D);
+ for (i=0; i<n; i++) DumpFunction(f->p[i],f->source,D);
+}
+
+static void DumpDebug(const Proto* f, DumpState* D)
+{
+ int i,n;
+ n= (D->strip) ? 0 : f->sizelineinfo;
+ DumpVector(f->lineinfo,n,sizeof(int),D);
+ n= (D->strip) ? 0 : f->sizelocvars;
+ DumpInt(n,D);
+ for (i=0; i<n; i++)
+ {
+  DumpString(f->locvars[i].varname,D);
+  DumpInt(f->locvars[i].startpc,D);
+  DumpInt(f->locvars[i].endpc,D);
+ }
+ n= (D->strip) ? 0 : f->sizeupvalues;
+ DumpInt(n,D);
+ for (i=0; i<n; i++) DumpString(f->upvalues[i],D);
+}
+
+static void DumpFunction(const Proto* f, const TString* p, DumpState* D)
+{
+ DumpString((f->source==p || D->strip) ? NULL : f->source,D);
+ DumpInt(f->linedefined,D);
+ DumpInt(f->lastlinedefined,D);
+ DumpChar(f->nups,D);
+ DumpChar(f->numparams,D);
+ DumpChar(f->is_vararg,D);
+ DumpChar(f->maxstacksize,D);
+ DumpCode(f,D);
+ DumpConstants(f,D);
+ DumpDebug(f,D);
+}
+
+static void DumpHeader(DumpState* D)
+{
+ char h[LUAC_HEADERSIZE];
+ luaU_header(h);
+ DumpBlock(h,LUAC_HEADERSIZE,D);
+}
+
+/*
+** dump Lua function as precompiled chunk
+*/
+int luaU_dump (lua_State* L, const Proto* f, lua_Writer w, void* data, int strip)
+{
+ DumpState D;
+ D.L=L;
+ D.writer=w;
+ D.data=data;
+ D.strip=strip;
+ D.status=0;
+ DumpHeader(&D);
+ DumpFunction(f,NULL,&D);
+ return D.status;
+}
diff --git a/com32/lua/src/lfunc.c b/com32/lua/src/lfunc.c
new file mode 100644
index 00000000..813e88f5
--- /dev/null
+++ b/com32/lua/src/lfunc.c
@@ -0,0 +1,174 @@
+/*
+** $Id: lfunc.c,v 2.12.1.2 2007/12/28 14:58:43 roberto Exp $
+** Auxiliary functions to manipulate prototypes and closures
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stddef.h>
+
+#define lfunc_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "lfunc.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+
+
+
+Closure *luaF_newCclosure (lua_State *L, int nelems, Table *e) {
+  Closure *c = cast(Closure *, luaM_malloc(L, sizeCclosure(nelems)));
+  luaC_link(L, obj2gco(c), LUA_TFUNCTION);
+  c->c.isC = 1;
+  c->c.env = e;
+  c->c.nupvalues = cast_byte(nelems);
+  return c;
+}
+
+
+Closure *luaF_newLclosure (lua_State *L, int nelems, Table *e) {
+  Closure *c = cast(Closure *, luaM_malloc(L, sizeLclosure(nelems)));
+  luaC_link(L, obj2gco(c), LUA_TFUNCTION);
+  c->l.isC = 0;
+  c->l.env = e;
+  c->l.nupvalues = cast_byte(nelems);
+  while (nelems--) c->l.upvals[nelems] = NULL;
+  return c;
+}
+
+
+UpVal *luaF_newupval (lua_State *L) {
+  UpVal *uv = luaM_new(L, UpVal);
+  luaC_link(L, obj2gco(uv), LUA_TUPVAL);
+  uv->v = &uv->u.value;
+  setnilvalue(uv->v);
+  return uv;
+}
+
+
+UpVal *luaF_findupval (lua_State *L, StkId level) {
+  global_State *g = G(L);
+  GCObject **pp = &L->openupval;
+  UpVal *p;
+  UpVal *uv;
+  while (*pp != NULL && (p = ngcotouv(*pp))->v >= level) {
+    lua_assert(p->v != &p->u.value);
+    if (p->v == level) {  /* found a corresponding upvalue? */
+      if (isdead(g, obj2gco(p)))  /* is it dead? */
+        changewhite(obj2gco(p));  /* ressurect it */
+      return p;
+    }
+    pp = &p->next;
+  }
+  uv = luaM_new(L, UpVal);  /* not found: create a new one */
+  uv->tt = LUA_TUPVAL;
+  uv->marked = luaC_white(g);
+  uv->v = level;  /* current value lives in the stack */
+  uv->next = *pp;  /* chain it in the proper position */
+  *pp = obj2gco(uv);
+  uv->u.l.prev = &g->uvhead;  /* double link it in `uvhead' list */
+  uv->u.l.next = g->uvhead.u.l.next;
+  uv->u.l.next->u.l.prev = uv;
+  g->uvhead.u.l.next = uv;
+  lua_assert(uv->u.l.next->u.l.prev == uv && uv->u.l.prev->u.l.next == uv);
+  return uv;
+}
+
+
+static void unlinkupval (UpVal *uv) {
+  lua_assert(uv->u.l.next->u.l.prev == uv && uv->u.l.prev->u.l.next == uv);
+  uv->u.l.next->u.l.prev = uv->u.l.prev;  /* remove from `uvhead' list */
+  uv->u.l.prev->u.l.next = uv->u.l.next;
+}
+
+
+void luaF_freeupval (lua_State *L, UpVal *uv) {
+  if (uv->v != &uv->u.value)  /* is it open? */
+    unlinkupval(uv);  /* remove from open list */
+  luaM_free(L, uv);  /* free upvalue */
+}
+
+
+void luaF_close (lua_State *L, StkId level) {
+  UpVal *uv;
+  global_State *g = G(L);
+  while (L->openupval != NULL && (uv = ngcotouv(L->openupval))->v >= level) {
+    GCObject *o = obj2gco(uv);
+    lua_assert(!isblack(o) && uv->v != &uv->u.value);
+    L->openupval = uv->next;  /* remove from `open' list */
+    if (isdead(g, o))
+      luaF_freeupval(L, uv);  /* free upvalue */
+    else {
+      unlinkupval(uv);
+      setobj(L, &uv->u.value, uv->v);
+      uv->v = &uv->u.value;  /* now current value lives here */
+      luaC_linkupval(L, uv);  /* link upvalue into `gcroot' list */
+    }
+  }
+}
+
+
+Proto *luaF_newproto (lua_State *L) {
+  Proto *f = luaM_new(L, Proto);
+  luaC_link(L, obj2gco(f), LUA_TPROTO);
+  f->k = NULL;
+  f->sizek = 0;
+  f->p = NULL;
+  f->sizep = 0;
+  f->code = NULL;
+  f->sizecode = 0;
+  f->sizelineinfo = 0;
+  f->sizeupvalues = 0;
+  f->nups = 0;
+  f->upvalues = NULL;
+  f->numparams = 0;
+  f->is_vararg = 0;
+  f->maxstacksize = 0;
+  f->lineinfo = NULL;
+  f->sizelocvars = 0;
+  f->locvars = NULL;
+  f->linedefined = 0;
+  f->lastlinedefined = 0;
+  f->source = NULL;
+  return f;
+}
+
+
+void luaF_freeproto (lua_State *L, Proto *f) {
+  luaM_freearray(L, f->code, f->sizecode, Instruction);
+  luaM_freearray(L, f->p, f->sizep, Proto *);
+  luaM_freearray(L, f->k, f->sizek, TValue);
+  luaM_freearray(L, f->lineinfo, f->sizelineinfo, int);
+  luaM_freearray(L, f->locvars, f->sizelocvars, struct LocVar);
+  luaM_freearray(L, f->upvalues, f->sizeupvalues, TString *);
+  luaM_free(L, f);
+}
+
+
+void luaF_freeclosure (lua_State *L, Closure *c) {
+  int size = (c->c.isC) ? sizeCclosure(c->c.nupvalues) :
+                          sizeLclosure(c->l.nupvalues);
+  luaM_freemem(L, c, size);
+}
+
+
+/*
+** Look for n-th local variable at line `line' in function `func'.
+** Returns NULL if not found.
+*/
+const char *luaF_getlocalname (const Proto *f, int local_number, int pc) {
+  int i;
+  for (i = 0; i<f->sizelocvars && f->locvars[i].startpc <= pc; i++) {
+    if (pc < f->locvars[i].endpc) {  /* is variable active? */
+      local_number--;
+      if (local_number == 0)
+        return getstr(f->locvars[i].varname);
+    }
+  }
+  return NULL;  /* not found */
+}
+
diff --git a/com32/lua/src/lfunc.h b/com32/lua/src/lfunc.h
new file mode 100644
index 00000000..a68cf515
--- /dev/null
+++ b/com32/lua/src/lfunc.h
@@ -0,0 +1,34 @@
+/*
+** $Id: lfunc.h,v 2.4.1.1 2007/12/27 13:02:25 roberto Exp $
+** Auxiliary functions to manipulate prototypes and closures
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lfunc_h
+#define lfunc_h
+
+
+#include "lobject.h"
+
+
+#define sizeCclosure(n)	(cast(int, sizeof(CClosure)) + \
+                         cast(int, sizeof(TValue)*((n)-1)))
+
+#define sizeLclosure(n)	(cast(int, sizeof(LClosure)) + \
+                         cast(int, sizeof(TValue *)*((n)-1)))
+
+
+LUAI_FUNC Proto *luaF_newproto (lua_State *L);
+LUAI_FUNC Closure *luaF_newCclosure (lua_State *L, int nelems, Table *e);
+LUAI_FUNC Closure *luaF_newLclosure (lua_State *L, int nelems, Table *e);
+LUAI_FUNC UpVal *luaF_newupval (lua_State *L);
+LUAI_FUNC UpVal *luaF_findupval (lua_State *L, StkId level);
+LUAI_FUNC void luaF_close (lua_State *L, StkId level);
+LUAI_FUNC void luaF_freeproto (lua_State *L, Proto *f);
+LUAI_FUNC void luaF_freeclosure (lua_State *L, Closure *c);
+LUAI_FUNC void luaF_freeupval (lua_State *L, UpVal *uv);
+LUAI_FUNC const char *luaF_getlocalname (const Proto *func, int local_number,
+                                         int pc);
+
+
+#endif
diff --git a/com32/lua/src/lgc.c b/com32/lua/src/lgc.c
new file mode 100644
index 00000000..d9e0b782
--- /dev/null
+++ b/com32/lua/src/lgc.c
@@ -0,0 +1,711 @@
+/*
+** $Id: lgc.c,v 2.38.1.1 2007/12/27 13:02:25 roberto Exp $
+** Garbage Collector
+** See Copyright Notice in lua.h
+*/
+
+#include <string.h>
+
+#define lgc_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+
+
+#define GCSTEPSIZE	1024u
+#define GCSWEEPMAX	40
+#define GCSWEEPCOST	10
+#define GCFINALIZECOST	100
+
+
+#define maskmarks	cast_byte(~(bitmask(BLACKBIT)|WHITEBITS))
+
+#define makewhite(g,x)	\
+   ((x)->gch.marked = cast_byte(((x)->gch.marked & maskmarks) | luaC_white(g)))
+
+#define white2gray(x)	reset2bits((x)->gch.marked, WHITE0BIT, WHITE1BIT)
+#define black2gray(x)	resetbit((x)->gch.marked, BLACKBIT)
+
+#define stringmark(s)	reset2bits((s)->tsv.marked, WHITE0BIT, WHITE1BIT)
+
+
+#define isfinalized(u)		testbit((u)->marked, FINALIZEDBIT)
+#define markfinalized(u)	l_setbit((u)->marked, FINALIZEDBIT)
+
+
+#define KEYWEAK         bitmask(KEYWEAKBIT)
+#define VALUEWEAK       bitmask(VALUEWEAKBIT)
+
+
+
+#define markvalue(g,o) { checkconsistency(o); \
+  if (iscollectable(o) && iswhite(gcvalue(o))) reallymarkobject(g,gcvalue(o)); }
+
+#define markobject(g,t) { if (iswhite(obj2gco(t))) \
+		reallymarkobject(g, obj2gco(t)); }
+
+
+#define setthreshold(g)  (g->GCthreshold = (g->estimate/100) * g->gcpause)
+
+
+static void removeentry (Node *n) {
+  lua_assert(ttisnil(gval(n)));
+  if (iscollectable(gkey(n)))
+    setttype(gkey(n), LUA_TDEADKEY);  /* dead key; remove it */
+}
+
+
+static void reallymarkobject (global_State *g, GCObject *o) {
+  lua_assert(iswhite(o) && !isdead(g, o));
+  white2gray(o);
+  switch (o->gch.tt) {
+    case LUA_TSTRING: {
+      return;
+    }
+    case LUA_TUSERDATA: {
+      Table *mt = gco2u(o)->metatable;
+      gray2black(o);  /* udata are never gray */
+      if (mt) markobject(g, mt);
+      markobject(g, gco2u(o)->env);
+      return;
+    }
+    case LUA_TUPVAL: {
+      UpVal *uv = gco2uv(o);
+      markvalue(g, uv->v);
+      if (uv->v == &uv->u.value)  /* closed? */
+        gray2black(o);  /* open upvalues are never black */
+      return;
+    }
+    case LUA_TFUNCTION: {
+      gco2cl(o)->c.gclist = g->gray;
+      g->gray = o;
+      break;
+    }
+    case LUA_TTABLE: {
+      gco2h(o)->gclist = g->gray;
+      g->gray = o;
+      break;
+    }
+    case LUA_TTHREAD: {
+      gco2th(o)->gclist = g->gray;
+      g->gray = o;
+      break;
+    }
+    case LUA_TPROTO: {
+      gco2p(o)->gclist = g->gray;
+      g->gray = o;
+      break;
+    }
+    default: lua_assert(0);
+  }
+}
+
+
+static void marktmu (global_State *g) {
+  GCObject *u = g->tmudata;
+  if (u) {
+    do {
+      u = u->gch.next;
+      makewhite(g, u);  /* may be marked, if left from previous GC */
+      reallymarkobject(g, u);
+    } while (u != g->tmudata);
+  }
+}
+
+
+/* move `dead' udata that need finalization to list `tmudata' */
+size_t luaC_separateudata (lua_State *L, int all) {
+  global_State *g = G(L);
+  size_t deadmem = 0;
+  GCObject **p = &g->mainthread->next;
+  GCObject *curr;
+  while ((curr = *p) != NULL) {
+    if (!(iswhite(curr) || all) || isfinalized(gco2u(curr)))
+      p = &curr->gch.next;  /* don't bother with them */
+    else if (fasttm(L, gco2u(curr)->metatable, TM_GC) == NULL) {
+      markfinalized(gco2u(curr));  /* don't need finalization */
+      p = &curr->gch.next;
+    }
+    else {  /* must call its gc method */
+      deadmem += sizeudata(gco2u(curr));
+      markfinalized(gco2u(curr));
+      *p = curr->gch.next;
+      /* link `curr' at the end of `tmudata' list */
+      if (g->tmudata == NULL)  /* list is empty? */
+        g->tmudata = curr->gch.next = curr;  /* creates a circular list */
+      else {
+        curr->gch.next = g->tmudata->gch.next;
+        g->tmudata->gch.next = curr;
+        g->tmudata = curr;
+      }
+    }
+  }
+  return deadmem;
+}
+
+
+static int traversetable (global_State *g, Table *h) {
+  int i;
+  int weakkey = 0;
+  int weakvalue = 0;
+  const TValue *mode;
+  if (h->metatable)
+    markobject(g, h->metatable);
+  mode = gfasttm(g, h->metatable, TM_MODE);
+  if (mode && ttisstring(mode)) {  /* is there a weak mode? */
+    weakkey = (strchr(svalue(mode), 'k') != NULL);
+    weakvalue = (strchr(svalue(mode), 'v') != NULL);
+    if (weakkey || weakvalue) {  /* is really weak? */
+      h->marked &= ~(KEYWEAK | VALUEWEAK);  /* clear bits */
+      h->marked |= cast_byte((weakkey << KEYWEAKBIT) |
+                             (weakvalue << VALUEWEAKBIT));
+      h->gclist = g->weak;  /* must be cleared after GC, ... */
+      g->weak = obj2gco(h);  /* ... so put in the appropriate list */
+    }
+  }
+  if (weakkey && weakvalue) return 1;
+  if (!weakvalue) {
+    i = h->sizearray;
+    while (i--)
+      markvalue(g, &h->array[i]);
+  }
+  i = sizenode(h);
+  while (i--) {
+    Node *n = gnode(h, i);
+    lua_assert(ttype(gkey(n)) != LUA_TDEADKEY || ttisnil(gval(n)));
+    if (ttisnil(gval(n)))
+      removeentry(n);  /* remove empty entries */
+    else {
+      lua_assert(!ttisnil(gkey(n)));
+      if (!weakkey) markvalue(g, gkey(n));
+      if (!weakvalue) markvalue(g, gval(n));
+    }
+  }
+  return weakkey || weakvalue;
+}
+
+
+/*
+** All marks are conditional because a GC may happen while the
+** prototype is still being created
+*/
+static void traverseproto (global_State *g, Proto *f) {
+  int i;
+  if (f->source) stringmark(f->source);
+  for (i=0; i<f->sizek; i++)  /* mark literals */
+    markvalue(g, &f->k[i]);
+  for (i=0; i<f->sizeupvalues; i++) {  /* mark upvalue names */
+    if (f->upvalues[i])
+      stringmark(f->upvalues[i]);
+  }
+  for (i=0; i<f->sizep; i++) {  /* mark nested protos */
+    if (f->p[i])
+      markobject(g, f->p[i]);
+  }
+  for (i=0; i<f->sizelocvars; i++) {  /* mark local-variable names */
+    if (f->locvars[i].varname)
+      stringmark(f->locvars[i].varname);
+  }
+}
+
+
+
+static void traverseclosure (global_State *g, Closure *cl) {
+  markobject(g, cl->c.env);
+  if (cl->c.isC) {
+    int i;
+    for (i=0; i<cl->c.nupvalues; i++)  /* mark its upvalues */
+      markvalue(g, &cl->c.upvalue[i]);
+  }
+  else {
+    int i;
+    lua_assert(cl->l.nupvalues == cl->l.p->nups);
+    markobject(g, cl->l.p);
+    for (i=0; i<cl->l.nupvalues; i++)  /* mark its upvalues */
+      markobject(g, cl->l.upvals[i]);
+  }
+}
+
+
+static void checkstacksizes (lua_State *L, StkId max) {
+  int ci_used = cast_int(L->ci - L->base_ci);  /* number of `ci' in use */
+  int s_used = cast_int(max - L->stack);  /* part of stack in use */
+  if (L->size_ci > LUAI_MAXCALLS)  /* handling overflow? */
+    return;  /* do not touch the stacks */
+  if (4*ci_used < L->size_ci && 2*BASIC_CI_SIZE < L->size_ci)
+    luaD_reallocCI(L, L->size_ci/2);  /* still big enough... */
+  condhardstacktests(luaD_reallocCI(L, ci_used + 1));
+  if (4*s_used < L->stacksize &&
+      2*(BASIC_STACK_SIZE+EXTRA_STACK) < L->stacksize)
+    luaD_reallocstack(L, L->stacksize/2);  /* still big enough... */
+  condhardstacktests(luaD_reallocstack(L, s_used));
+}
+
+
+static void traversestack (global_State *g, lua_State *l) {
+  StkId o, lim;
+  CallInfo *ci;
+  markvalue(g, gt(l));
+  lim = l->top;
+  for (ci = l->base_ci; ci <= l->ci; ci++) {
+    lua_assert(ci->top <= l->stack_last);
+    if (lim < ci->top) lim = ci->top;
+  }
+  for (o = l->stack; o < l->top; o++)
+    markvalue(g, o);
+  for (; o <= lim; o++)
+    setnilvalue(o);
+  checkstacksizes(l, lim);
+}
+
+
+/*
+** traverse one gray object, turning it to black.
+** Returns `quantity' traversed.
+*/
+static l_mem propagatemark (global_State *g) {
+  GCObject *o = g->gray;
+  lua_assert(isgray(o));
+  gray2black(o);
+  switch (o->gch.tt) {
+    case LUA_TTABLE: {
+      Table *h = gco2h(o);
+      g->gray = h->gclist;
+      if (traversetable(g, h))  /* table is weak? */
+        black2gray(o);  /* keep it gray */
+      return sizeof(Table) + sizeof(TValue) * h->sizearray +
+                             sizeof(Node) * sizenode(h);
+    }
+    case LUA_TFUNCTION: {
+      Closure *cl = gco2cl(o);
+      g->gray = cl->c.gclist;
+      traverseclosure(g, cl);
+      return (cl->c.isC) ? sizeCclosure(cl->c.nupvalues) :
+                           sizeLclosure(cl->l.nupvalues);
+    }
+    case LUA_TTHREAD: {
+      lua_State *th = gco2th(o);
+      g->gray = th->gclist;
+      th->gclist = g->grayagain;
+      g->grayagain = o;
+      black2gray(o);
+      traversestack(g, th);
+      return sizeof(lua_State) + sizeof(TValue) * th->stacksize +
+                                 sizeof(CallInfo) * th->size_ci;
+    }
+    case LUA_TPROTO: {
+      Proto *p = gco2p(o);
+      g->gray = p->gclist;
+      traverseproto(g, p);
+      return sizeof(Proto) + sizeof(Instruction) * p->sizecode +
+                             sizeof(Proto *) * p->sizep +
+                             sizeof(TValue) * p->sizek + 
+                             sizeof(int) * p->sizelineinfo +
+                             sizeof(LocVar) * p->sizelocvars +
+                             sizeof(TString *) * p->sizeupvalues;
+    }
+    default: lua_assert(0); return 0;
+  }
+}
+
+
+static size_t propagateall (global_State *g) {
+  size_t m = 0;
+  while (g->gray) m += propagatemark(g);
+  return m;
+}
+
+
+/*
+** The next function tells whether a key or value can be cleared from
+** a weak table. Non-collectable objects are never removed from weak
+** tables. Strings behave as `values', so are never removed too. for
+** other objects: if really collected, cannot keep them; for userdata
+** being finalized, keep them in keys, but not in values
+*/
+static int iscleared (const TValue *o, int iskey) {
+  if (!iscollectable(o)) return 0;
+  if (ttisstring(o)) {
+    stringmark(rawtsvalue(o));  /* strings are `values', so are never weak */
+    return 0;
+  }
+  return iswhite(gcvalue(o)) ||
+    (ttisuserdata(o) && (!iskey && isfinalized(uvalue(o))));
+}
+
+
+/*
+** clear collected entries from weaktables
+*/
+static void cleartable (GCObject *l) {
+  while (l) {
+    Table *h = gco2h(l);
+    int i = h->sizearray;
+    lua_assert(testbit(h->marked, VALUEWEAKBIT) ||
+               testbit(h->marked, KEYWEAKBIT));
+    if (testbit(h->marked, VALUEWEAKBIT)) {
+      while (i--) {
+        TValue *o = &h->array[i];
+        if (iscleared(o, 0))  /* value was collected? */
+          setnilvalue(o);  /* remove value */
+      }
+    }
+    i = sizenode(h);
+    while (i--) {
+      Node *n = gnode(h, i);
+      if (!ttisnil(gval(n)) &&  /* non-empty entry? */
+          (iscleared(key2tval(n), 1) || iscleared(gval(n), 0))) {
+        setnilvalue(gval(n));  /* remove value ... */
+        removeentry(n);  /* remove entry from table */
+      }
+    }
+    l = h->gclist;
+  }
+}
+
+
+static void freeobj (lua_State *L, GCObject *o) {
+  switch (o->gch.tt) {
+    case LUA_TPROTO: luaF_freeproto(L, gco2p(o)); break;
+    case LUA_TFUNCTION: luaF_freeclosure(L, gco2cl(o)); break;
+    case LUA_TUPVAL: luaF_freeupval(L, gco2uv(o)); break;
+    case LUA_TTABLE: luaH_free(L, gco2h(o)); break;
+    case LUA_TTHREAD: {
+      lua_assert(gco2th(o) != L && gco2th(o) != G(L)->mainthread);
+      luaE_freethread(L, gco2th(o));
+      break;
+    }
+    case LUA_TSTRING: {
+      G(L)->strt.nuse--;
+      luaM_freemem(L, o, sizestring(gco2ts(o)));
+      break;
+    }
+    case LUA_TUSERDATA: {
+      luaM_freemem(L, o, sizeudata(gco2u(o)));
+      break;
+    }
+    default: lua_assert(0);
+  }
+}
+
+
+
+#define sweepwholelist(L,p)	sweeplist(L,p,MAX_LUMEM)
+
+
+static GCObject **sweeplist (lua_State *L, GCObject **p, lu_mem count) {
+  GCObject *curr;
+  global_State *g = G(L);
+  int deadmask = otherwhite(g);
+  while ((curr = *p) != NULL && count-- > 0) {
+    if (curr->gch.tt == LUA_TTHREAD)  /* sweep open upvalues of each thread */
+      sweepwholelist(L, &gco2th(curr)->openupval);
+    if ((curr->gch.marked ^ WHITEBITS) & deadmask) {  /* not dead? */
+      lua_assert(!isdead(g, curr) || testbit(curr->gch.marked, FIXEDBIT));
+      makewhite(g, curr);  /* make it white (for next cycle) */
+      p = &curr->gch.next;
+    }
+    else {  /* must erase `curr' */
+      lua_assert(isdead(g, curr) || deadmask == bitmask(SFIXEDBIT));
+      *p = curr->gch.next;
+      if (curr == g->rootgc)  /* is the first element of the list? */
+        g->rootgc = curr->gch.next;  /* adjust first */
+      freeobj(L, curr);
+    }
+  }
+  return p;
+}
+
+
+static void checkSizes (lua_State *L) {
+  global_State *g = G(L);
+  /* check size of string hash */
+  if (g->strt.nuse < cast(lu_int32, g->strt.size/4) &&
+      g->strt.size > MINSTRTABSIZE*2)
+    luaS_resize(L, g->strt.size/2);  /* table is too big */
+  /* check size of buffer */
+  if (luaZ_sizebuffer(&g->buff) > LUA_MINBUFFER*2) {  /* buffer too big? */
+    size_t newsize = luaZ_sizebuffer(&g->buff) / 2;
+    luaZ_resizebuffer(L, &g->buff, newsize);
+  }
+}
+
+
+static void GCTM (lua_State *L) {
+  global_State *g = G(L);
+  GCObject *o = g->tmudata->gch.next;  /* get first element */
+  Udata *udata = rawgco2u(o);
+  const TValue *tm;
+  /* remove udata from `tmudata' */
+  if (o == g->tmudata)  /* last element? */
+    g->tmudata = NULL;
+  else
+    g->tmudata->gch.next = udata->uv.next;
+  udata->uv.next = g->mainthread->next;  /* return it to `root' list */
+  g->mainthread->next = o;
+  makewhite(g, o);
+  tm = fasttm(L, udata->uv.metatable, TM_GC);
+  if (tm != NULL) {
+    lu_byte oldah = L->allowhook;
+    lu_mem oldt = g->GCthreshold;
+    L->allowhook = 0;  /* stop debug hooks during GC tag method */
+    g->GCthreshold = 2*g->totalbytes;  /* avoid GC steps */
+    setobj2s(L, L->top, tm);
+    setuvalue(L, L->top+1, udata);
+    L->top += 2;
+    luaD_call(L, L->top - 2, 0);
+    L->allowhook = oldah;  /* restore hooks */
+    g->GCthreshold = oldt;  /* restore threshold */
+  }
+}
+
+
+/*
+** Call all GC tag methods
+*/
+void luaC_callGCTM (lua_State *L) {
+  while (G(L)->tmudata)
+    GCTM(L);
+}
+
+
+void luaC_freeall (lua_State *L) {
+  global_State *g = G(L);
+  int i;
+  g->currentwhite = WHITEBITS | bitmask(SFIXEDBIT);  /* mask to collect all elements */
+  sweepwholelist(L, &g->rootgc);
+  for (i = 0; i < g->strt.size; i++)  /* free all string lists */
+    sweepwholelist(L, &g->strt.hash[i]);
+}
+
+
+static void markmt (global_State *g) {
+  int i;
+  for (i=0; i<NUM_TAGS; i++)
+    if (g->mt[i]) markobject(g, g->mt[i]);
+}
+
+
+/* mark root set */
+static void markroot (lua_State *L) {
+  global_State *g = G(L);
+  g->gray = NULL;
+  g->grayagain = NULL;
+  g->weak = NULL;
+  markobject(g, g->mainthread);
+  /* make global table be traversed before main stack */
+  markvalue(g, gt(g->mainthread));
+  markvalue(g, registry(L));
+  markmt(g);
+  g->gcstate = GCSpropagate;
+}
+
+
+static void remarkupvals (global_State *g) {
+  UpVal *uv;
+  for (uv = g->uvhead.u.l.next; uv != &g->uvhead; uv = uv->u.l.next) {
+    lua_assert(uv->u.l.next->u.l.prev == uv && uv->u.l.prev->u.l.next == uv);
+    if (isgray(obj2gco(uv)))
+      markvalue(g, uv->v);
+  }
+}
+
+
+static void atomic (lua_State *L) {
+  global_State *g = G(L);
+  size_t udsize;  /* total size of userdata to be finalized */
+  /* remark occasional upvalues of (maybe) dead threads */
+  remarkupvals(g);
+  /* traverse objects cautch by write barrier and by 'remarkupvals' */
+  propagateall(g);
+  /* remark weak tables */
+  g->gray = g->weak;
+  g->weak = NULL;
+  lua_assert(!iswhite(obj2gco(g->mainthread)));
+  markobject(g, L);  /* mark running thread */
+  markmt(g);  /* mark basic metatables (again) */
+  propagateall(g);
+  /* remark gray again */
+  g->gray = g->grayagain;
+  g->grayagain = NULL;
+  propagateall(g);
+  udsize = luaC_separateudata(L, 0);  /* separate userdata to be finalized */
+  marktmu(g);  /* mark `preserved' userdata */
+  udsize += propagateall(g);  /* remark, to propagate `preserveness' */
+  cleartable(g->weak);  /* remove collected objects from weak tables */
+  /* flip current white */
+  g->currentwhite = cast_byte(otherwhite(g));
+  g->sweepstrgc = 0;
+  g->sweepgc = &g->rootgc;
+  g->gcstate = GCSsweepstring;
+  g->estimate = g->totalbytes - udsize;  /* first estimate */
+}
+
+
+static l_mem singlestep (lua_State *L) {
+  global_State *g = G(L);
+  /*lua_checkmemory(L);*/
+  switch (g->gcstate) {
+    case GCSpause: {
+      markroot(L);  /* start a new collection */
+      return 0;
+    }
+    case GCSpropagate: {
+      if (g->gray)
+        return propagatemark(g);
+      else {  /* no more `gray' objects */
+        atomic(L);  /* finish mark phase */
+        return 0;
+      }
+    }
+    case GCSsweepstring: {
+      lu_mem old = g->totalbytes;
+      sweepwholelist(L, &g->strt.hash[g->sweepstrgc++]);
+      if (g->sweepstrgc >= g->strt.size)  /* nothing more to sweep? */
+        g->gcstate = GCSsweep;  /* end sweep-string phase */
+      lua_assert(old >= g->totalbytes);
+      g->estimate -= old - g->totalbytes;
+      return GCSWEEPCOST;
+    }
+    case GCSsweep: {
+      lu_mem old = g->totalbytes;
+      g->sweepgc = sweeplist(L, g->sweepgc, GCSWEEPMAX);
+      if (*g->sweepgc == NULL) {  /* nothing more to sweep? */
+        checkSizes(L);
+        g->gcstate = GCSfinalize;  /* end sweep phase */
+      }
+      lua_assert(old >= g->totalbytes);
+      g->estimate -= old - g->totalbytes;
+      return GCSWEEPMAX*GCSWEEPCOST;
+    }
+    case GCSfinalize: {
+      if (g->tmudata) {
+        GCTM(L);
+        if (g->estimate > GCFINALIZECOST)
+          g->estimate -= GCFINALIZECOST;
+        return GCFINALIZECOST;
+      }
+      else {
+        g->gcstate = GCSpause;  /* end collection */
+        g->gcdept = 0;
+        return 0;
+      }
+    }
+    default: lua_assert(0); return 0;
+  }
+}
+
+
+void luaC_step (lua_State *L) {
+  global_State *g = G(L);
+  l_mem lim = (GCSTEPSIZE/100) * g->gcstepmul;
+  if (lim == 0)
+    lim = (MAX_LUMEM-1)/2;  /* no limit */
+  g->gcdept += g->totalbytes - g->GCthreshold;
+  do {
+    lim -= singlestep(L);
+    if (g->gcstate == GCSpause)
+      break;
+  } while (lim > 0);
+  if (g->gcstate != GCSpause) {
+    if (g->gcdept < GCSTEPSIZE)
+      g->GCthreshold = g->totalbytes + GCSTEPSIZE;  /* - lim/g->gcstepmul;*/
+    else {
+      g->gcdept -= GCSTEPSIZE;
+      g->GCthreshold = g->totalbytes;
+    }
+  }
+  else {
+    lua_assert(g->totalbytes >= g->estimate);
+    setthreshold(g);
+  }
+}
+
+
+void luaC_fullgc (lua_State *L) {
+  global_State *g = G(L);
+  if (g->gcstate <= GCSpropagate) {
+    /* reset sweep marks to sweep all elements (returning them to white) */
+    g->sweepstrgc = 0;
+    g->sweepgc = &g->rootgc;
+    /* reset other collector lists */
+    g->gray = NULL;
+    g->grayagain = NULL;
+    g->weak = NULL;
+    g->gcstate = GCSsweepstring;
+  }
+  lua_assert(g->gcstate != GCSpause && g->gcstate != GCSpropagate);
+  /* finish any pending sweep phase */
+  while (g->gcstate != GCSfinalize) {
+    lua_assert(g->gcstate == GCSsweepstring || g->gcstate == GCSsweep);
+    singlestep(L);
+  }
+  markroot(L);
+  while (g->gcstate != GCSpause) {
+    singlestep(L);
+  }
+  setthreshold(g);
+}
+
+
+void luaC_barrierf (lua_State *L, GCObject *o, GCObject *v) {
+  global_State *g = G(L);
+  lua_assert(isblack(o) && iswhite(v) && !isdead(g, v) && !isdead(g, o));
+  lua_assert(g->gcstate != GCSfinalize && g->gcstate != GCSpause);
+  lua_assert(ttype(&o->gch) != LUA_TTABLE);
+  /* must keep invariant? */
+  if (g->gcstate == GCSpropagate)
+    reallymarkobject(g, v);  /* restore invariant */
+  else  /* don't mind */
+    makewhite(g, o);  /* mark as white just to avoid other barriers */
+}
+
+
+void luaC_barrierback (lua_State *L, Table *t) {
+  global_State *g = G(L);
+  GCObject *o = obj2gco(t);
+  lua_assert(isblack(o) && !isdead(g, o));
+  lua_assert(g->gcstate != GCSfinalize && g->gcstate != GCSpause);
+  black2gray(o);  /* make table gray (again) */
+  t->gclist = g->grayagain;
+  g->grayagain = o;
+}
+
+
+void luaC_link (lua_State *L, GCObject *o, lu_byte tt) {
+  global_State *g = G(L);
+  o->gch.next = g->rootgc;
+  g->rootgc = o;
+  o->gch.marked = luaC_white(g);
+  o->gch.tt = tt;
+}
+
+
+void luaC_linkupval (lua_State *L, UpVal *uv) {
+  global_State *g = G(L);
+  GCObject *o = obj2gco(uv);
+  o->gch.next = g->rootgc;  /* link upvalue into `rootgc' list */
+  g->rootgc = o;
+  if (isgray(o)) { 
+    if (g->gcstate == GCSpropagate) {
+      gray2black(o);  /* closed upvalues need barrier */
+      luaC_barrier(L, uv, uv->v);
+    }
+    else {  /* sweep phase: sweep it (turning it into white) */
+      makewhite(g, o);
+      lua_assert(g->gcstate != GCSfinalize && g->gcstate != GCSpause);
+    }
+  }
+}
+
diff --git a/com32/lua/src/lgc.h b/com32/lua/src/lgc.h
new file mode 100644
index 00000000..5a8dc605
--- /dev/null
+++ b/com32/lua/src/lgc.h
@@ -0,0 +1,110 @@
+/*
+** $Id: lgc.h,v 2.15.1.1 2007/12/27 13:02:25 roberto Exp $
+** Garbage Collector
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lgc_h
+#define lgc_h
+
+
+#include "lobject.h"
+
+
+/*
+** Possible states of the Garbage Collector
+*/
+#define GCSpause	0
+#define GCSpropagate	1
+#define GCSsweepstring	2
+#define GCSsweep	3
+#define GCSfinalize	4
+
+
+/*
+** some userful bit tricks
+*/
+#define resetbits(x,m)	((x) &= cast(lu_byte, ~(m)))
+#define setbits(x,m)	((x) |= (m))
+#define testbits(x,m)	((x) & (m))
+#define bitmask(b)	(1<<(b))
+#define bit2mask(b1,b2)	(b