Project import
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..b18805f
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,110 @@
+#
+# Copyright (c) 2010-2011 Nest, Inc.
+# All rights reserved.
+#
+# This document is the property of Nest. It is considered
+# confidential and proprietary information.
+#
+# This document may not be reproduced or transmitted in any form,
+# in whole or in part, without the express written permission of
+# Nest.
+#
+# Description:
+# This Makefile is used to build lua, a lightweight scripting language.
+# This package produces both a standalone lua interpreter and a C binding library.
+#
+
+BuildConfigSpecialized := No
+BuildProductSpecialized := No
+
+include pre.mak
+
+PackageName := lua
+
+PackageExtension := tar.gz
+PackageSeparator := -
+
+PackagePatchArgs := -p1
+
+PackageArchive := $(PackageName).$(PackageExtension)
+PackageSourceDir := $(PackageName)$(PackageSeparator)$(PackageVersion)
+
+PackageBuildMakefile = $(call GenerateBuildPaths,Makefile)
+
+CleanPaths += $(PackageLicenseFile)
+
+all: $(PackageDefaultGoal)
+
+# Generate the package license contents.
+
+$(PackageSourceDir)/COPYRIGHT: source
+
+$(PackageLicenseFile): $(PackageSourceDir)/COPYRIGHT
+ $(copy-result)
+
+# Extract the source from the archive and apply patches, if any.
+
+$(PackageSourceDir): $(PackageArchive) $(PackagePatchPaths)
+ $(expand-and-patch-package)
+
+# Prepare the sources.
+
+.PHONY: source
+source: | ${PackageSourceDir}
+
+# Patch the sources, if necessary.
+
+.PHONY: patch
+patch: source
+
+# Generate the package build makefile.
+
+$(PackageBuildMakefile): | $(PackageSourceDir) $(BuildDirectory)
+ $(call create-links,$(CURDIR)/$(PackageSourceDir),$(BuildDirectory))
+
+# Configure the source for building.
+
+.PHONY: configure
+configure: patch | ${PackageBuildMakefile}
+
+# Build the source.
+#
+# We have to unset MAKEFLAGS since they confuse the package build otherwise.
+
+ifeq ($(TargetOS),darwin)
+MYLIBS="-ldl"
+PLAT=macosx
+else
+MYLIBS="-Wl,-E -ldl"
+PLAT=posix
+endif
+
+.PHONY: build
+build: configure | $(BuildDirectory)
+ $(Verbose)unset MAKEFLAGS && \
+ $(MAKE) $(JOBSFLAG) -C $(BuildDirectory)/src \
+ CC="$(CC)" AR="$(AR) -cr" NM=$(NM) RANLIB=$(RANLIB) STRIP=$(STRIP) \
+ INSTALL="$(INSTALL) $(INSTALLFLAGS)" \
+ PLAT=$(PLAT) \
+ MYCFLAGS="-DLUA_USE_POSIX -DLUA_USE_DLOPEN" \
+ MYLIBS=$(MYLIBS) \
+ all
+
+# Stage the build to a temporary installation area.
+#
+# We have to unset MAKEFLAGS since they confuse the package build otherwise.
+
+.PHONY: stage
+stage: build | $(ResultDirectory)
+ $(Verbose)unset MAKEFLAGS && \
+ $(MAKE) $(JOBSFLAG) -C $(BuildDirectory) \
+ INSTALL="$(INSTALL) $(INSTALLFLAGS)" \
+ INSTALL_TOP=$(ResultDirectory) \
+ install
+
+clean:
+ $(Verbose)$(RM) $(RMFLAGS) -r $(PackageSourceDir)
+ $(Verbose)$(RM) $(RMFLAGS) -r $(BuildDirectory)
+ $(Verbose)$(RM) $(RMFLAGS) -r $(ResultDirectory)
+
+include post.mak
diff --git a/lua-5.1.4/COPYRIGHT b/lua-5.1.4/COPYRIGHT
new file mode 100644
index 0000000..3a53e74
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/HISTORY b/lua-5.1.4/HISTORY
new file mode 100644
index 0000000..ce0c95b
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/INSTALL b/lua-5.1.4/INSTALL
new file mode 100644
index 0000000..17eb8ae
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/Makefile b/lua-5.1.4/Makefile
new file mode 100644
index 0000000..6e78f66
--- /dev/null
+++ b/lua-5.1.4/Makefile
@@ -0,0 +1,128 @@
+# 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 and doc directories,
+# so take care if INSTALL_TOP is not an absolute path.
+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
+#
+# You probably want to make INSTALL_LMOD and INSTALL_CMOD consistent with
+# LUA_ROOT, LUA_LDIR, and LUA_CDIR in luaconf.h (and also with etc/lua.pc).
+INSTALL_LMOD= $(INSTALL_TOP)/share/lua/$V
+INSTALL_CMOD= $(INSTALL_TOP)/lib/lua/$V
+
+# How to install. If your install program does not support "-p", then you
+# may have to run ranlib on the installed liblua.a (do "make ranlib").
+INSTALL= install -p
+INSTALL_EXEC= $(INSTALL) -m 0755
+INSTALL_DATA= $(INSTALL) -m 0644
+#
+# If you don't have install you can use cp instead.
+# INSTALL= cp -p
+# INSTALL_EXEC= $(INSTALL)
+# INSTALL_DATA= $(INSTALL)
+
+# Utilities.
+MKDIR= mkdir -p
+RANLIB= ranlib
+
+# == 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= 5.1.4
+
+all: $(PLAT)
+
+$(PLATS) clean:
+ cd src && $(MAKE) $@
+
+test: dummy
+ src/lua test/hello.lua
+
+install: dummy
+ cd src && $(MKDIR) $(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)
+
+ranlib:
+ cd src && cd $(INSTALL_LIB) && $(RANLIB) $(TO_LIB)
+
+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/lua-5.1.4/README b/lua-5.1.4/README
new file mode 100644
index 0000000..11b4dff
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/doc/amazon.gif b/lua-5.1.4/doc/amazon.gif
new file mode 100644
index 0000000..f2586d5
--- /dev/null
+++ b/lua-5.1.4/doc/amazon.gif
Binary files differ
diff --git a/lua-5.1.4/doc/contents.html b/lua-5.1.4/doc/contents.html
new file mode 100644
index 0000000..8e58e18
--- /dev/null
+++ b/lua-5.1.4/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>
+·
+<A HREF="#contents">contents</A>
+·
+<A HREF="#index">index</A>
+·
+<A HREF="http://www.lua.org/manual/5.1/pt/">português</A>
+·
+<A HREF="http://www.lua.org/manual/5.1/es/">español</A>
+<HR>
+<SMALL>
+Copyright © 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> </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>
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diff --git a/lua-5.1.4/doc/lua.1 b/lua-5.1.4/doc/lua.1
new file mode 100644
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--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/doc/lua.css b/lua-5.1.4/doc/lua.css
new file mode 100644
index 0000000..039cf11
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/doc/lua.html b/lua-5.1.4/doc/lua.html
new file mode 100644
index 0000000..1d435ab
--- /dev/null
+++ b/lua-5.1.4/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 "> " and ">> ".
+<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/lua-5.1.4/doc/luac.1 b/lua-5.1.4/doc/luac.1
new file mode 100644
index 0000000..d814678
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/doc/luac.html b/lua-5.1.4/doc/luac.html
new file mode 100644
index 0000000..179ffe8
--- /dev/null
+++ b/lua-5.1.4/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>
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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" type="text/css" href="lua.css">
+<link rel="stylesheet" type="text/css" 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 © 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>
+·
+<a href="contents.html#index">index</A>
+
+<!-- ====================================================================== -->
+<p>
+
+<!-- $Id: manual.of,v 1.48 2008/08/18 15:24:20 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 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 functions to be called by Lua code.
+Through the use of C 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>} means 0 or more <em>a</em>'s, and
+[<em>a</em>] 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>´.
+The complete syntax of Lua can be found in <a href="#8">§8</a>
+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 <a href="#pdf-_VERSION"><code>_VERSION</code></a>)
+are reserved for internal global variables used by Lua.
+
+
+<p>
+The following strings denote other tokens:
+
+<pre>
+ + - * / % ^ #
+ == ~= <= >= < > =
+ ( ) { } [ ]
+ ; : , . .. ...
+</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 can 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 can contain any 8-bit value, including embedded zeros,
+which can be specified as '<code>\0</code>'.
+
+
+<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 0 is written as <code>[[</code>,
+an opening long bracket of level 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 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 can run for several lines,
+do not interpret any escape sequences,
+and ignore long brackets of any other level.
+They can 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 97,
+newline is coded as 10, and '<code>1</code>' is coded as 49),
+the five literal strings 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> can 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 can contain any 8-bit character,
+including embedded zeros ('<code>\0</code>') (see <a href="#2.1">§2.1</a>).
+
+
+<p>
+Lua can call (and manipulate) functions written in Lua and
+functions written in C
+(see <a href="#2.5.8">§2.5.8</a>).
+
+
+<p>
+The type <em>userdata</em> is provided to allow arbitrary C 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">§2.8</a>).
+Userdata values cannot be created or modified in Lua,
+only through the C 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">§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 can 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">§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 can contain functions.
+Thus tables can also carry <em>methods</em> (see <a href="#2.5.9">§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">§2.1</a>.
+
+
+<p>
+Any variable is assumed to be global unless explicitly declared
+as a local (see <a href="#2.4.7">§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">§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>´ exp `<b>]</b>´
+</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">§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>´ 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">§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 functions
+through the debug library; (see <a href="#5.9">§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">§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
+assignments, 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>´]}
+</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">§2.5.9</a>).
+As such, chunks can define local variables,
+receive arguments, and return values.
+
+
+<p>
+A chunk can be stored in a file or in a string inside the host program.
+To execute a chunk,
+Lua first pre-compiles the chunk into instructions for a virtual machine,
+and then it executes the compiled code
+with an interpreter for the virtual machine.
+
+
+<p>
+Chunks can 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 can 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">§2.4.4</a>).
+
+
+
+
+
+<h3>2.4.3 - <a name="2.4.3">Assignment</a></h3>
+
+<p>
+Lua allows multiple assignments.
+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>´ explist
+ varlist ::= var {`<b>,</b>´ var}
+ explist ::= exp {`<b>,</b>´ exp}
+</pre><p>
+Expressions are discussed in <a href="#2.5">§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 that call enter the list of values,
+before the adjustment
+(except when the call is enclosed in parentheses; see <a href="#2.5">§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 4.
+Similarly, the line
+
+<pre>
+ x, y = y, x
+</pre><p>
+exchanges the values of <code>x</code> and <code>y</code>,
+and
+
+<pre>
+ x, y, z = y, z, x
+</pre><p>
+cyclically permutes the values of <code>x</code>, <code>y</code>, and <code>z</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">§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">§2.4.5</a>).
+
+
+<p>
+The condition expression of a
+control structure can 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>–<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 can return more than one value,
+and 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>´ exp `<b>,</b>´ exp [`<b>,</b>´ 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> > 0 and <em>var</em> <= <em>limit</em>) or (<em>step</em> <= 0 and <em>var</em> >= <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 shown here are for explanatory purposes only.
+</li>
+
+<li>
+If the third expression (the step) is absent,
+then a step of 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>´ Name}
+</pre><p>
+A <b>for</b> statement like
+
+<pre>
+ for <em>var_1</em>, ···, <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>, ···, <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">§2.5.8</a>.
+
+
+
+
+
+<h3>2.4.7 - <a name="2.4.7">Local Declarations</a></h3><p>
+Local variables can be declared anywhere inside a block.
+The declaration can include an initial assignment:
+
+<pre>
+ stat ::= <b>local</b> namelist [`<b>=</b>´ explist]
+</pre><p>
+If present, an initial assignment has the same semantics
+of a multiple assignment (see <a href="#2.4.3">§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">§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">§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>´
+ exp ::= exp binop exp
+ exp ::= unop exp
+ prefixexp ::= var | functioncall | `<b>(</b>´ exp `<b>)</b>´
+</pre>
+
+<p>
+Numbers and literal strings are explained in <a href="#2.1">§2.1</a>;
+variables are explained in <a href="#2.3">§2.3</a>;
+function definitions are explained in <a href="#2.5.9">§2.5.9</a>;
+function calls are explained in <a href="#2.5.8">§2.5.8</a>;
+table constructors are explained in <a href="#2.5.7">§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">§2.5.9</a>.
+
+
+<p>
+Binary operators comprise arithmetic operators (see <a href="#2.5.1">§2.5.1</a>),
+relational operators (see <a href="#2.5.2">§2.5.2</a>), logical operators (see <a href="#2.5.3">§2.5.3</a>),
+and the concatenation operator (see <a href="#2.5.4">§2.5.4</a>).
+Unary operators comprise the unary minus (see <a href="#2.5.1">§2.5.1</a>),
+the unary <b>not</b> (see <a href="#2.5.3">§2.5.3</a>),
+and the unary <em>length operator</em> (see <a href="#2.5.5">§2.5.5</a>).
+
+
+<p>
+Both function calls and vararg expressions can result in multiple values.
+If an expression is used as a statement
+(only possible for function calls (see <a href="#2.4.6">§2.4.6</a>)),
+then its return list is adjusted to zero elements,
+thus discarding all returned values.
+If an 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 can 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>
+Any 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">§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>
+ == ~= < > <= >=
+</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">§2.8</a>).
+
+
+<p>
+The conversion rules of <a href="#2.2.1">§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">§2.8</a>).
+A comparison <code>a > b</code> is translated to <code>b < a</code>
+and <code>a >= b</code> is translated to <code>b <= a</code>.
+
+
+
+
+
+<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">§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 --> 10
+ 10 or error() --> 10
+ nil or "a" --> "a"
+ nil and 10 --> nil
+ false and error() --> false
+ false and nil --> false
+ false or nil --> nil
+ 10 and 20 --> 20
+</pre><p>
+(In this manual,
+<code>--></code> 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">§2.2.1</a>.
+Otherwise, the "concat" metamethod is called (see <a href="#2.8">§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> can 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> can 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
+ < > <= >= ~= ==
+ ..
+ + -
+ * / %
+ 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.
+A constructor can be used to create an empty table
+or to create a table and initialize some of its fields.
+The general syntax for constructors is
+
+<pre>
+ tableconstructor ::= `<b>{</b>´ [fieldlist] `<b>}</b>´
+ fieldlist ::= field {fieldsep field} [fieldsep]
+ field ::= `<b>[</b>´ exp `<b>]</b>´ `<b>=</b>´ exp | Name `<b>=</b>´ exp | exp
+ fieldsep ::= `<b>,</b>´ | `<b>;</b>´
+</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">§2.5.8</a>).
+To avoid this,
+enclose the function call or the vararg expression
+in parentheses (see <a href="#2.5">§2.5</a>).
+
+
+<p>
+The field list can 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">§2.8</a>).
+
+
+<p>
+The form
+
+<pre>
+ functioncall ::= prefixexp `<b>:</b>´ 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>´ [explist] `<b>)</b>´
+ 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>´ [parlist] `<b>)</b>´ 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>´ Name} [`<b>:</b>´ 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
+can refer to different external local variables
+and can have different environment tables.
+
+
+<p>
+Parameters act as local variables that are
+initialized with the argument values:
+
+<pre>
+ parlist ::= namelist [`<b>,</b>´ `<b>...</b>´] | `<b>...</b>´
+</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 that last expression 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, ... --> (nothing)
+ g(3, 4) a=3, b=4, ... --> (nothing)
+ g(3, 4, 5, 8) a=3, b=4, ... --> 5 8
+ g(5, r()) a=5, b=1, ... --> 2 3
+</pre>
+
+<p>
+Results are returned using the <b>return</b> statement (see <a href="#2.4.4">§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) --> 10
+ x = x+1
+ do -- another block
+ local x = x+1 -- another 'x'
+ print(x) --> 12
+ end
+ print(x) --> 11
+ end
+ print(x) --> 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 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 can 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 by using the debug library);
+you must use the C 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;
+that is, there is one single metatable for all numbers,
+one for all strings, etc.
+
+
+<p>
+A metatable controls how an object behaves in arithmetic operations,
+order comparisons, concatenation, length operation, and indexing.
+A metatable also can 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">§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(···)
+ 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 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(···)
+ 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(···)
+ 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(···)
+ end
+ end
+ end
+</pre><p>
+See <a href="#2.5.5">§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><</code> operation.
+
+
+<pre>
+ function lt_event (op1, op2)
+ if type(op1) == "number" and type(op2) == "number" then
+ return op1 < op2 -- numeric comparison
+ elseif type(op1) == "string" and type(op2) == "string" then
+ return op1 < op2 -- lexicographic comparison
+ else
+ local h = getcomphandler(op1, op2, "__lt")
+ if h then
+ return (h(op1, op2))
+ else
+ error(···)
+ end
+ end
+ end
+</pre><p>
+<code>a > b</code> is equivalent to <code>b < a</code>.
+</li>
+
+<li><b>"le":</b>
+the <code><=</code> operation.
+
+
+<pre>
+ function le_event (op1, op2)
+ if type(op1) == "number" and type(op2) == "number" then
+ return op1 <= op2 -- numeric comparison
+ elseif type(op1) == "string" and type(op2) == "string" then
+ return op1 <= 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(···)
+ end
+ end
+ end
+ end
+</pre><p>
+<code>a >= b</code> is equivalent to <code>b <= a</code>.
+Note that, in the absence of a "le" metamethod,
+Lua tries the "lt", assuming that <code>a <= b</code> is
+equivalent to <code>not (b < 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(···)
+ 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(···)
+ 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(···)
+ 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>
+Threads are created sharing the environment of the creating thread.
+Userdata and C functions are created sharing the environment
+of the creating C function.
+Non-nested Lua functions
+(created by <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>)
+are created sharing the environment of the creating thread.
+Nested Lua functions are created sharing the environment of
+the creating Lua function.
+
+
+<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 threads and
+non-nested Lua functions created by the thread
+and can be directly accessed by C code (see <a href="#3.3">§3.3</a>).
+
+
+<p>
+The environment associated with a C function can be directly
+accessed by C code (see <a href="#3.3">§3.3</a>).
+It is used as the default environment for other C functions
+and userdata 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">§2.3</a>).
+They are used as the default environment for nested 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 functions, other threads) you must
+use the C 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, objects that are no longer accessible from Lua).
+All memory used by Lua is subject to automatic management:
+tables, userdata, functions, threads, strings, etc.
+
+
+<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>.
+Both use percentage points as units
+(so that a value of 100 means an internal value of 1).
+
+
+<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 100 mean the collector will not wait to
+start a new cycle.
+A value of 200 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 100 make the collector too slow and
+can result in the collector never finishing a cycle.
+The default, 200, 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.
+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 API,
+you can set garbage-collector metamethods for userdata (see <a href="#2.8">§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 '<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 <code>__mode</code> field.
+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
+a 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 API for Lua, that is,
+the set of C 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 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 functions that are still active.
+This stack initially contains any arguments to the C function
+and it is where the C 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 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 1 represents the first element
+(that is, the element that was pushed onto the stack first)
+and
+index <em>n</em> represents the last element;
+index -1 also represents the last element
+(that is, the element at the top)
+and index <em>-n</em> represents the first element.
+We say that an index is <em>valid</em>
+if it lies between 1 and the stack top
+(that is, if <code>1 ≤ abs(index) ≤ 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 < 0 && abs(index) <= top) ||
+ (index > 0 && index <= 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 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 function (see <a href="#3.4">§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 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 function is created,
+it is possible to associate some values with it,
+thus creating a <em>C 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 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 (but not greater than 256),
+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 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 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 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 can 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 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 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 can 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 >= 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 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 can 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 can do the
+equivalent to this Lua code:
+
+<pre>
+ a = f("how", t.x, 14)
+</pre><p>
+Here it is in 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 functions.
+
+
+<p>
+In order to communicate properly with Lua,
+a C function must use the following protocol,
+which defines the way parameters and results are passed:
+a C 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 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 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 <= 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> is 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">§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 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 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 0.
+Also returns 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> as the new value
+for the <em>pause</em> of the collector (see <a href="#2.10">§2.10</a>).
+The function returns the previous value of the pause.
+</li>
+
+<li><b><code>LUA_GCSETSTEPMUL</code>:</b>
+sets <code>data</code> as the new value for the <em>step multiplier</em> of
+the collector (see <a href="#2.10">§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">§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 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">§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 1,
+this result is equal to the number of elements in the stack
+(and so 0 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 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 function,
+and 0 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 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 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 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 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 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 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 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 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 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 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><</code> operator
+(that is, may call metamethods).
+Otherwise returns 0.
+Also returns 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">§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 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 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 closure onto the stack.
+
+
+<p>
+When a C function is created,
+it is possible to associate some values with it,
+thus creating a C closure (see <a href="#3.4">§3.4</a>);
+these values are then accessible to the function whenever it is called.
+To associate values with a C 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 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.
+
+
+<p>
+The maximum value for <code>n</code> is 255.
+
+
+
+
+
+<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 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 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 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 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 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 0.
+Also returns 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> or set <code>size</code> to zero.
+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">§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">§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 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 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 boolean
+value (0 or 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 function.
+That value must be a C 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">§2.2.1</a>);
+otherwise, <a href="#lua_tointeger"><code>lua_tointeger</code></a> returns 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 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 C),
+but can 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 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">§2.2.1</a>);
+otherwise, <a href="#lua_tonumber"><code>lua_tonumber</code></a> returns 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 pointer (<code>void*</code>).
+The value can 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 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 function, as follows:
+
+<pre>
+ return lua_yield (L, nresults);
+</pre><p>
+When a C 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 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 can be the value of multiple global variables,
+while others can 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>></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, ">S", &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 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 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 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> can 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 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 #<narg> to <func> (<extramsg>)
+</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 #<narg> to <func> (<extramsg>)
+</pre>
+
+<p>
+This function never returns,
+but it is an idiom to use it in C 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 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, &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(&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 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 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 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 0 is the running function,
+level 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 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 API
+and are provided as separate C modules.
+Currently, Lua has the following standard libraries:
+
+<ul>
+
+<li>basic library,</li> which includes the coroutine sub-library;
+
+<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 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 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> as the new value for the <em>pause</em> of
+the collector (see <a href="#2.10">§2.10</a>).
+Returns the previous value for <em>pause</em>.
+</li>
+
+<li><b>"setstepmul":</b>
+sets <code>arg</code> as the new value for the <em>step multiplier</em> of
+the collector (see <a href="#2.10">§2.10</a>).
+Returns the previous value for <em>step</em>.
+</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 1 (the default), the error position is where the
+<code>error</code> function was called.
+Level 2 points the error to where the function
+that called <code>error</code> was called; and so on.
+Passing a level 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 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>), ···,
+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 an empty string, <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–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, ···)</code></a></h3>
+
+
+<p>
+Calls function <code>f</code> with
+the given arguments in <em>protected mode</em>.
+This means that any error inside <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 (···)</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, ···)</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 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 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 10, the letter '<code>A</code>' (in either upper or lower case)
+represents 10, '<code>B</code>' represents 11, and so forth,
+with '<code>Z</code>' representing 35.
+In base 10 (the default), the number can have a decimal part,
+as well as an optional exponent part (see <a href="#2.1">§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], ···, 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 1 and <code>j</code> is the length of the list,
+as defined by the length operator (see <a href="#2.5.5">§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">§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, ···])</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>, ··· are passed
+as the arguments to the body function.
+If the coroutine has yielded,
+<code>resume</code> restarts it;
+the values <code>val1</code>, ··· 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 (···)</code></a></h3>
+
+
+<p>
+Suspends the execution of the calling coroutine.
+The coroutine cannot be running a C 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 [, ···])</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 can 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 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 loader.
+
+
+<p>
+Lua initializes the C 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 can 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 library,
+using the path given by the variable <a href="#pdf-package.cpath"><code>package.cpath</code></a>.
+For instance,
+if the C 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 library,
+this searcher first uses a dynamic link facility to link the
+application with the library.
+Then it tries to find a C function inside the library to
+be used as the loader.
+The name of this C 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 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 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 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 library <code>libname</code>.
+Inside this library, looks for a function <code>funcname</code>
+and returns this function as a C 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 library,
+including if necessary a path and extension.
+<code>funcname</code> must be the exact name exported by the C library
+(which may depend on the C 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 1
+(not at 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>
+The string library assumes one-byte character encodings.
+
+
+<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>, ···, <code>s[j]</code>.
+The default value for <code>i</code> is 1;
+the default value for <code>j</code> is <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 (···)</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 <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 1 and can 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, ···)</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 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 can 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 <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 <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")
+ --> x="hello hello world world"
+
+ x = string.gsub("hello world", "%w+", "%0 %0", 1)
+ --> x="hello hello world"
+
+ x = string.gsub("hello world from Lua", "(%w+)%s*(%w+)", "%2 %1")
+ --> x="world hello Lua from"
+
+ x = string.gsub("home = $HOME, user = $USER", "%$(%w+)", os.getenv)
+ --> x="home = /home/roberto, user = roberto"
+
+ x = string.gsub("4+5 = $return 4+5$", "%$(.-)%$", function (s)
+ return loadstring(s)()
+ end)
+ --> x="4+5 = 9"
+
+ local t = {name="lua", version="5.1"}
+ x = string.gsub("$name-$version.tar.gz", "%$(%w+)", t)
+ --> 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 1 and can 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> can 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 can be specified by
+separating the end characters of the range with a '<code>-</code>'.
+All classes <code>%</code><em>x</em> described above can 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> can 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 <em>x</em>, end with <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 can 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 1);
+the character matching "<code>.</code>" is captured with number 2,
+and the part matching "<code>%s*</code>" has number 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 and 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] ··· 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">§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><</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 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>
+that rounds the quotient towards zero.
+
+
+
+
+<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, ···)</code></a></h3>
+
+
+<p>
+Returns the maximum value among its arguments.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-math.min"><code>math.min (x, ···)</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 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 can 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 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 (···)</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 (···)</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 (···)</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 (···)</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 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 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 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 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.
+
+
+<p>
+On some systems (POSIX),
+this function also creates a file with that name,
+to avoid security risks.
+(Someone else might create the file with wrong permissions
+in the time between getting the name and creating the file.)
+You still have to open the file to use it
+and to remove it (even if you do not use it).
+
+
+<p>
+When possible,
+you may prefer to use <a href="#pdf-io.tmpfile"><code>io.tmpfile</code></a>,
+which automatically removes the file when the program ends.
+
+
+
+
+
+
+
+<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 0 is the current function (<code>getinfo</code> itself);
+level 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 can 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 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 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">§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>,
+when simulating a return from a tail call),
+<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 2 to get more information about
+the running function
+(level 0 is the <code>getinfo</code> function,
+and level 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 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>, ···
+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> '" -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 <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 5.0 to Lua 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 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>´]} [laststat [`<b>;</b>´]]
+
+ block ::= chunk
+
+ stat ::= varlist `<b>=</b>´ 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>´ exp `<b>,</b>´ exp [`<b>,</b>´ 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>´ explist]
+
+ laststat ::= <b>return</b> [explist] | <b>break</b>
+
+ funcname ::= Name {`<b>.</b>´ Name} [`<b>:</b>´ Name]
+
+ varlist ::= var {`<b>,</b>´ var}
+
+ var ::= Name | prefixexp `<b>[</b>´ exp `<b>]</b>´ | prefixexp `<b>.</b>´ Name
+
+ namelist ::= Name {`<b>,</b>´ Name}
+
+ explist ::= {exp `<b>,</b>´} exp
+
+ exp ::= <b>nil</b> | <b>false</b> | <b>true</b> | Number | String | `<b>...</b>´ | function |
+ prefixexp | tableconstructor | exp binop exp | unop exp
+
+ prefixexp ::= var | functioncall | `<b>(</b>´ exp `<b>)</b>´
+
+ functioncall ::= prefixexp args | prefixexp `<b>:</b>´ Name args
+
+ args ::= `<b>(</b>´ [explist] `<b>)</b>´ | tableconstructor | String
+
+ function ::= <b>function</b> funcbody
+
+ funcbody ::= `<b>(</b>´ [parlist] `<b>)</b>´ block <b>end</b>
+
+ parlist ::= namelist [`<b>,</b>´ `<b>...</b>´] | `<b>...</b>´
+
+ tableconstructor ::= `<b>{</b>´ [fieldlist] `<b>}</b>´
+
+ fieldlist ::= field {fieldsep field} [fieldsep]
+
+ field ::= `<b>[</b>´ exp `<b>]</b>´ `<b>=</b>´ exp | Name `<b>=</b>´ exp | exp
+
+ fieldsep ::= `<b>,</b>´ | `<b>;</b>´
+
+ binop ::= `<b>+</b>´ | `<b>-</b>´ | `<b>*</b>´ | `<b>/</b>´ | `<b>^</b>´ | `<b>%</b>´ | `<b>..</b>´ |
+ `<b><</b>´ | `<b><=</b>´ | `<b>></b>´ | `<b>>=</b>´ | `<b>==</b>´ | `<b>~=</b>´ |
+ <b>and</b> | <b>or</b>
+
+ unop ::= `<b>-</b>´ | <b>not</b> | `<b>#</b>´
+
+</pre>
+
+<p>
+
+
+
+
+
+
+
+<HR>
+<SMALL>
+Last update:
+Mon Aug 18 13:25:46 BRT 2008
+</SMALL>
+<!--
+Last change: revised for Lua 5.1.4
+-->
+
+</body></html>
+
diff --git a/lua-5.1.4/doc/readme.html b/lua-5.1.4/doc/readme.html
new file mode 100644
index 0000000..38be6db
--- /dev/null
+++ b/lua-5.1.4/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 5.1.4.
+
+<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:
+Tue Aug 12 14:46:07 BRT 2008
+</SMALL>
+
+</BODY>
+</HTML>
diff --git a/lua-5.1.4/etc/Makefile b/lua-5.1.4/etc/Makefile
new file mode 100644
index 0000000..6d00008
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/etc/README b/lua-5.1.4/etc/README
new file mode 100644
index 0000000..5149fc9
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/etc/all.c b/lua-5.1.4/etc/all.c
new file mode 100644
index 0000000..dab68fa
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/etc/lua.hpp b/lua-5.1.4/etc/lua.hpp
new file mode 100644
index 0000000..ec417f5
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/etc/lua.ico b/lua-5.1.4/etc/lua.ico
new file mode 100644
index 0000000..ccbabc4
--- /dev/null
+++ b/lua-5.1.4/etc/lua.ico
Binary files differ
diff --git a/lua-5.1.4/etc/lua.pc b/lua-5.1.4/etc/lua.pc
new file mode 100644
index 0000000..f52f55b
--- /dev/null
+++ b/lua-5.1.4/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= 5.1.4
+
+# 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/lua-5.1.4/etc/luavs.bat b/lua-5.1.4/etc/luavs.bat
new file mode 100644
index 0000000..08c2bed
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/etc/min.c b/lua-5.1.4/etc/min.c
new file mode 100644
index 0000000..6a85a4d
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/etc/noparser.c b/lua-5.1.4/etc/noparser.c
new file mode 100644
index 0000000..13ba546
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/etc/strict.lua b/lua-5.1.4/etc/strict.lua
new file mode 100644
index 0000000..604619d
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/src/Makefile b/lua-5.1.4/src/Makefile
new file mode 100644
index 0000000..e4a3cd6
--- /dev/null
+++ b/lua-5.1.4/src/Makefile
@@ -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/lua-5.1.4/src/lapi.c b/lua-5.1.4/src/lapi.c
new file mode 100644
index 0000000..5d5145d
--- /dev/null
+++ b/lua-5.1.4/src/lapi.c
@@ -0,0 +1,1087 @@
+/*
+** $Id: lapi.c,v 2.55.1.5 2008/07/04 18:41:18 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 = 1;
+ lua_lock(L);
+ if (size > LUAI_MAXCSTACK || (L->top - L->base + size) > LUAI_MAXCSTACK)
+ res = 0; /* stack overflow */
+ else if (size > 0) {
+ luaD_checkstack(L, size);
+ if (L->ci->top < L->top + size)
+ L->ci->top = L->top + size;
+ }
+ 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;
+ }
+ }
+ 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/lua-5.1.4/src/lapi.h b/lua-5.1.4/src/lapi.h
new file mode 100644
index 0000000..2c3fab2
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/src/lauxlib.c b/lua-5.1.4/src/lauxlib.c
new file mode 100644
index 0000000..10f14e2
--- /dev/null
+++ b/lua-5.1.4/src/lauxlib.c
@@ -0,0 +1,652 @@
+/*
+** $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);
+ }
+ 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);
+ 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/lua-5.1.4/src/lauxlib.h b/lua-5.1.4/src/lauxlib.h
new file mode 100644
index 0000000..3425823
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/src/lbaselib.c b/lua-5.1.4/src/lbaselib.c
new file mode 100644
index 0000000..2a4c079
--- /dev/null
+++ b/lua-5.1.4/src/lbaselib.c
@@ -0,0 +1,653 @@
+/*
+** $Id: lbaselib.c,v 1.191.1.6 2008/02/14 16:46:22 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));
+ if (i > e) return 0; /* empty range */
+ n = e - i + 1; /* number of elements */
+ if (n <= 0 || !lua_checkstack(L, n)) /* n <= 0 means arith. overflow */
+ return luaL_error(L, "too many results to unpack");
+ lua_rawgeti(L, 1, i); /* push arg[i] (avoiding overflow problems) */
+ while (i++ < e) /* push arg[i + 1...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 + 1))
+ 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/lua-5.1.4/src/lcode.c b/lua-5.1.4/src/lcode.c
new file mode 100644
index 0000000..cff626b
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/src/lcode.h b/lua-5.1.4/src/lcode.h
new file mode 100644
index 0000000..b941c60
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/src/ldblib.c b/lua-5.1.4/src/ldblib.c
new file mode 100644
index 0000000..67de122
--- /dev/null
+++ b/lua-5.1.4/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/lua-5.1.4/src/ldebug.c b/lua-5.1.4/src/ldebug.c
new file mode 100644
index 0000000..50ad3d3
--- /dev/null
+++ b/lua-5.1.4/src/ldebug.c
@@ -0,0 +1,638 @@
+/*
+** $Id: ldebug.c,v 2.29.1.6 2008/05/08 16:56:26 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) {
