Initial import of lua-5.2-beta. No COPYRIGHT is provided in the source.

116 files changed, 12756 insertions, 10553 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1eeb08a..cf521ca 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -15,11 +15,12 @@ set ( LUA_CPATH "LUA_CPATH" CACHE STRING "Environment variable to use as package
 set ( LUA_INIT "LUA_INIT" CACHE STRING "Environment variable for initial script." )
 
 option ( LUA_ANSI "Use only ansi features." OFF )
-option ( LUA_USE_RELATIVE_LOADLIB "Use modified loadlib.c with support for relative paths on posix systems." ON)
+option ( LUA_USE_RELATIVE_LOADLIB "Use modified loadlib.c with support for relative paths on posix systems." ON )
+option ( LUA_COMPAT_ALL "Enable backwards compatibility options." ON )
 set ( LUA_IDSIZE 60 CACHE NUMBER "gives the maximum size for the description of the source." )
-set ( LUA_PROMPT "> " CACHE STRING "Is the default prompt used by stand-alone Lua." )
-set ( LUA_PROMPT2 ">> " CACHE STRING "Is the default continuation prompt used by stand-alone Lua." )
-set ( LUA_MAXINPUT 512 CACHE NUMBER "Is the maximum length for an input line in the stand-alone interpreter.")
+#set ( LUA_PROMPT "> " CACHE STRING "Is the default prompt used by stand-alone Lua." )
+#set ( LUA_PROMPT2 ">> " CACHE STRING "Is the default continuation prompt used by stand-alone Lua." )
+#set ( LUA_MAXINPUT 512 CACHE NUMBER "Is the maximum length for an input line in the stand-alone interpreter.")
 
 #2DO: LUAI_* and LUAL_* settings, for now defaults are used.
   
@@ -58,6 +59,9 @@ else ()
   option ( LUA_USE_ISATTY "Use tty." ON )
   option ( LUA_USE_POPEN "Use popen." ON )
   option ( LUA_USE_ULONGJMP "Use ulongjmp" ON)
+  option ( LUA_USE_STRTODHEX "assume 'strtod' handles hexa formats" ON )
+  option ( LUA_USE_AFORMAT "assume 'printf' handles 'aA' specifiers" ON )
+  option ( LUA_USE_LONGLONG "assume support for long long" ON)
 endif ()
 
 ## SETUP
@@ -83,16 +87,6 @@ if ( LUA_USE_DLOPEN )
   list ( APPEND LIBS dl )
 endif ()
 
-if ( LUA_WIN )
-  # Add extra rc files to the windows build
-  if ( MSVC OR MINGW )
-    set ( LUA_DEF src/lua.def )
-    set ( LUA_DLL_RC src/lua_dll.rc )
-    set ( LUA_RC src/lua.rc )
-    set ( LUAC_RC src/luac.rc )
-  endif ()
-endif ()
-
 if ( LUA_USE_READLINE )
   # Add readline
   include_directories ( ${READLINE_INCLUDE_DIR} )
@@ -111,9 +105,41 @@ configure_file ( src/luaconf.h.in ${CMAKE_CURRENT_BINARY_DIR}/luaconf.h )
 
 # Sources and headers
 include_directories ( src ${CMAKE_CURRENT_BINARY_DIR} )
-set ( SRC_LIB src/lapi.c src/lcode.c src/ldebug.c src/ldo.c src/ldump.c src/lfunc.c src/lgc.c src/llex.c src/lmem.c src/lobject.c src/lopcodes.c src/lparser.c src/lstate.c src/lstring.c src/ltable.c src/ltm.c src/lundump.c src/lvm.c src/lzio.c src/lauxlib.c src/lbaselib.c src/ldblib.c src/liolib.c src/lmathlib.c src/loslib.c src/ltablib.c src/lstrlib.c src/linit.c )
+set ( SRC_CORE
+	src/lapi.c
+	src/lcode.c
+	src/lctype.c
+	src/ldebug.c
+	src/ldo.c
+	src/ldump.c
+	src/lfunc.c
+	src/lgc.c
+	src/llex.c
+	src/lmem.c
+	src/lobject.c
+	src/lopcodes.c
+	src/lparser.c
+	src/lstate.c
+	src/lstring.c
+	src/ltable.c
+	src/ltm.c
+	src/lundump.c
+	src/lvm.c
+	src/lzio.c)
+set ( SRC_LIB
+	src/lauxlib.c
+	src/lbaselib.c
+	src/lbitlib.c
+	src/lcorolib.c
+	src/ldblib.c
+	src/liolib.c
+	src/lmathlib.c
+	src/loslib.c
+	src/lstrlib.c
+	src/ltablib.c
+	src/linit.c)
 set ( SRC_LUA src/lua.c )
-set ( SRC_LUAC src/luac.c src/print.c )
+set ( SRC_LUAC src/luac.c )
 
 if ( LUA_USE_RELATIVE_LOADLIB )
   # Use modified loadlib
@@ -123,54 +149,22 @@ else ()
 endif ()
 
 ## BUILD
-# Create dynamic library
-add_library ( liblua SHARED ${SRC_LIB} ${LUA_DLL_RC} ${LUA_DEF} )
+# Create lua library
+add_library ( liblua SHARED ${SRC_CORE} ${SRC_LIB} ${LUA_DLL_RC} ${LUA_DEF} )
 target_link_libraries ( liblua ${LIBS} )
 set_target_properties ( liblua PROPERTIES OUTPUT_NAME lua CLEAN_DIRECT_OUTPUT 1 )
 
-# Create static library, this is needed to compile luac in the 5.1.x Lua series
-add_library ( liblua_static STATIC ${SRC_LIB} )
-target_link_libraries ( liblua_static ${LIBS} )
-
-add_executable ( lua ${SRC_LUA} ${LUA_RC} )
+add_executable ( lua ${SRC_LUA} src/lua.rc )
 target_link_libraries ( lua liblua )
 
-add_executable ( luac ${SRC_LUAC} ${LUAC_RC} )
-target_link_libraries ( luac liblua_static )
+add_executable ( luac ${SRC_LUAC} src/luac.rc )
+target_link_libraries ( luac liblua )
 
 install_executable ( lua luac )
 install_library ( liblua )
-install_data ( README COPYRIGHT HISTORY )
-install_lua_module ( strict etc/strict.lua )
-install_header (src/lua.h src/lualib.h src/lauxlib.h etc/lua.hpp ${CMAKE_CURRENT_BINARY_DIR}/luaconf.h  )
+install_data ( README )
+#install_lua_module ( strict etc/strict.lua )
+install_header (src/lua.h src/lualib.h src/lauxlib.h ${CMAKE_CURRENT_BINARY_DIR}/luaconf.h  )
 install_doc ( doc/ )
 install_foo ( etc/ )
-install_test ( test/ )
-
-## TESTS
-set(LUA lua) 
-
-add_lua_test ( test/bisect.lua )
-add_lua_test ( test/cf.lua )
-add_lua_test ( test/echo.lua )
-add_lua_test ( test/env.lua )
-add_lua_test ( test/factorial.lua )
-add_lua_test ( test/fib.lua 20 )
-add_lua_test ( test/fibfor.lua )
-#add_lua_test ( test/globals.lua ) # Requires input
-add_lua_test ( test/hello.lua )
-file(READ test/life.lua _data)  # life.lua test, with reduced run-time.
-string(REPLACE "40,20" "20,15" _data "${_data}")
-string(REPLACE 2000 20 _data "${_data}")
-file(WRITE ${CMAKE_CURRENT_BINARY_DIR}/test/life-quick.lua "${_data}")
-add_lua_test ( ${CMAKE_CURRENT_BINARY_DIR}/test/life-quick.lua )
-#add_lua_test ( test/luac.lua ) # Requires input
-add_lua_test ( test/printf.lua )
-add_lua_test ( test/readonly.lua )
-#set_property ( TEST readonly PROPERTY PASS_REGULAR_EXPRESSION "cannot redefine global variable `y'" )
-add_lua_test ( test/sieve.lua )
-add_lua_test ( test/sort.lua )
-#add_lua_test ( test/table.lua ) # Requires input
-add_lua_test ( test/trace-calls.lua )
-add_lua_test ( test/trace-globals.lua )
-#add_lua_test ( test/xd.lua ) # Requires input
+#install_test ( test/ )
diff --git a/COPYRIGHT b/COPYRIGHT
deleted file mode 100644
index 3a53e74..0000000
--- a/COPYRIGHT
+++ /dev/null
@@ -1,34 +0,0 @@
-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/HISTORY b/HISTORY
deleted file mode 100644
index ce0c95b..0000000
--- a/HISTORY
+++ /dev/null
@@ -1,183 +0,0 @@
-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/INSTALL b/INSTALL
deleted file mode 100644
index 17eb8ae..0000000
--- a/INSTALL
+++ /dev/null
@@ -1,99 +0,0 @@
-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/Makefile b/Makefile
index 6e78f66..da62ab9 100644..100755
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,5 @@
-# makefile for installing Lua
-# see INSTALL for installation instructions
-# see src/Makefile and src/luaconf.h for further customization
+# Makefile for installing Lua
+# See doc/readme.html for installation and customization instructions.
 
 # == CHANGE THE SETTINGS BELOW TO SUIT YOUR ENVIRONMENT =======================
 
@@ -8,119 +7,106 @@
 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.
+# so take care if INSTALL_TOP is not an absolute path. See the local target.
+# You may want to make INSTALL_LMOD and INSTALL_CMOD consistent with
+# LUA_ROOT, LUA_LDIR, and LUA_CDIR in luaconf.h.
 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").
+# How to install. If your install program does not support "-p", then
+# you may have to run ranlib on the installed liblua.a.
 INSTALL= install -p
 INSTALL_EXEC= $(INSTALL) -m 0755
 INSTALL_DATA= $(INSTALL) -m 0644
 #
-# If you don't have install you can use cp instead.
+# If you don't have "install" you can use "cp" instead.
 # INSTALL= cp -p
 # INSTALL_EXEC= $(INSTALL)
 # INSTALL_DATA= $(INSTALL)
 
-# Utilities.
+# Other utilities.
 MKDIR= mkdir -p
-RANLIB= ranlib
+RM= rm -f
 
-# == END OF USER SETTINGS. NO NEED TO CHANGE ANYTHING BELOW THIS LINE =========
+# == 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_INC= lua.h luaconf.h lualib.h lauxlib.h lua.hpp
 TO_LIB= liblua.a
 TO_MAN= lua.1 luac.1
 
 # Lua version and release.
-V= 5.1
-R= 5.1.4
+V= 5.2
+R= $V.0
 
+# Targets start here.
 all:	$(PLAT)
 
 $(PLATS) clean:
 	cd src && $(MAKE) $@
 
 test:	dummy
-	src/lua test/hello.lua
+	src/lua -v
 
 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)
+	#cd doc && $(INSTALL_DATA) $(TO_MAN) $(INSTALL_MAN)
 
-ranlib:
-	cd src && cd $(INSTALL_LIB) && $(RANLIB) $(TO_LIB)
+uninstall:
+	cd src && cd $(INSTALL_BIN) && $(RM) $(TO_BIN)
+	cd src && cd $(INSTALL_INC) && $(RM) $(TO_INC)
+	cd src && cd $(INSTALL_LIB) && $(RM) $(TO_LIB)
+	#cd doc && cd $(INSTALL_MAN) && $(RM) $(TO_MAN)
 
 local:
-	$(MAKE) install INSTALL_TOP=..
+	$(MAKE) install INSTALL_TOP=../install
 
 none:
-	@echo "Please do"
-	@echo "   make PLATFORM"
-	@echo "where PLATFORM is one of these:"
+	@echo "Please do 'make PLATFORM' where PLATFORM is one of these:"
 	@echo "   $(PLATS)"
-	@echo "See INSTALL for complete instructions."
+	@echo "See doc/readme.html for complete instructions."
 
-# make may get confused with test/ and INSTALL in a case-insensitive OS
+# make may get confused with test/ and install/
 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"
+	@echo "PLAT= $(PLAT)"
+	@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 "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= $(INSTALL_DATA)"
+
+# echo pkg-config data
+pc:
+	@echo "version=$R"
+	@echo "prefix=$(INSTALL_TOP)"
+	@echo "libdir=$(INSTALL_LIB)"
+	@echo "includedir=$(INSTALL_INC)"
 
 # 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
diff --git a/README b/README
index b028e7d..f00e8e7 100644..100755
--- a/README
+++ b/README
@@ -1,46 +1,6 @@
-README for Lua 5.1
 
-See INSTALL for installation instructions.
-See HISTORY for a summary of changes since the last released version.
+This is Lua 5.2 (beta), released on 05 Jul 2011.
 
-* 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 installation instructions, license details, and
+further information about Lua, see doc/readme.html.
 
-  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
-  ------------
-  In the LuaDist distribution the default makefiles have been replaced with
-  CMake. To build Lua use the following approach.
-  > mkdir _build && cd_build
-  > ccmake .. # Set up configuration, alternatively use cmake-gui on Windows.
-  > cmake --build . --target install
-  
-  The default makefile should work too, you just need to edit src/luaconf.h.orig
-  and save it as src/luaconf.h.
-  
-  > make
-  
-  See INSTALL for detailed instructions with make.
-
-* 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/dist.info b/dist.info
index 40ecbcb..2d9961d 100644
--- a/dist.info
+++ b/dist.info
@@ -1,7 +1,7 @@
 --- This file is part of LuaDist project
 
 name = "lua"
-version = "5.1.4"
+version = "5.2-beta"
 
 desc = "Lua is a powerful, fast, light-weight, embeddable scripting language."
 author = "Roberto Ierusalimschy, Waldemar Celes, Luiz Henrique de Figueiredo"
diff --git a/doc/alert.png b/doc/alert.png
new file mode 100755
index 0000000..4938074
--- /dev/null
+++ b/doc/alert.png
diff --git a/doc/amazon.gif b/doc/amazon.gif
deleted file mode 100644
index f2586d5..0000000
--- a/doc/amazon.gif
+++ /dev/null
diff --git a/doc/contents.html b/doc/contents.html
index 8e58e18..788bf6c 100644..100755
--- a/doc/contents.html
+++ b/doc/contents.html
@@ -1,7 +1,7 @@
 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
 <HTML>
 <HEAD>
-<TITLE>Lua 5.1 Reference Manual - contents</TITLE>
+<TITLE>Lua 5.2 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">
@@ -17,140 +17,125 @@ ul {
 <HR>
 <H1>
 <A HREF="http://www.lua.org/"><IMG SRC="logo.gif" ALT="" BORDER=0></A>
-Lua 5.1 Reference Manual
+Lua 5.2 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>
+<IMG SRC="alert.png" ALIGN="absbottom" ALT="[!]">
+<EM>This is a beta version of Lua 5.2.
+Some details may change in the final version.</EM>
 
-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>
 
+<P>
 <A HREF="manual.html">start</A>
 &middot;
 <A HREF="#contents">contents</A>
 &middot;
 <A HREF="#index">index</A>
-&middot;
-<A HREF="http://www.lua.org/manual/5.1/pt/">português</A>
-&middot;
-<A HREF="http://www.lua.org/manual/5.1/es/">español</A>
 <HR>
 <SMALL>
-Copyright &copy; 2006-2008 Lua.org, PUC-Rio.
+Copyright &copy; 2011 Lua.org, PUC-Rio.
 Freely available under the terms of the
-<a href="http://www.lua.org/license.html#5">Lua license</a>.
+<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>
+<LI><A HREF="manual.html">1 &ndash; Introduction</A>
 <P>
-<LI><A HREF="manual.html#2">2 - The Language</A>
+<LI><A HREF="manual.html#2">2 &ndash; Basic Concepts</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>
+<LI><A HREF="manual.html#2.1">2.1 &ndash; Values and Types</A>
+<LI><A HREF="manual.html#2.2">2.2 &ndash; Environments and the Global Environment</A>
+<LI><A HREF="manual.html#2.3">2.3 &ndash; Error Handling</A>
+<LI><A HREF="manual.html#2.4">2.4 &ndash; Metatables and Metamethods</A>
+<LI><A HREF="manual.html#2.5">2.5 &ndash; Garbage Collection</A>
 <UL>
-<LI><A HREF="manual.html#2.2.1">2.2.1 - Coercion</A>
+<LI><A HREF="manual.html#2.5.1">2.5.1 &ndash; Garbage-Collection Metamethods</A>
+<LI><A HREF="manual.html#2.5.2">2.5.2 &ndash; Weak Tables</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>
+<LI><A HREF="manual.html#2.6">2.6 &ndash; Coroutines</A>
 </UL>
-<LI><A HREF="manual.html#2.5">2.5 - Expressions</A>
+<P>
+<LI><A HREF="manual.html#3">3 &ndash; The Language</A>
+<UL>
+<LI><A HREF="manual.html#3.1">3.1 &ndash; Lexical Conventions</A>
+<LI><A HREF="manual.html#3.2">3.2 &ndash; Variables</A>
+<LI><A HREF="manual.html#3.3">3.3 &ndash; Statements</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>
+<LI><A HREF="manual.html#3.3.1">3.3.1 &ndash; Blocks</A>
+<LI><A HREF="manual.html#3.3.2">3.3.2 &ndash; Chunks</A>
+<LI><A HREF="manual.html#3.3.3">3.3.3 &ndash; Assignment</A>
+<LI><A HREF="manual.html#3.3.4">3.3.4 &ndash; Control Structures</A>
+<LI><A HREF="manual.html#3.3.5">3.3.5 &ndash; For Statement</A>
+<LI><A HREF="manual.html#3.3.6">3.3.6 &ndash; Function Calls as Statements</A>
+<LI><A HREF="manual.html#3.3.7">3.3.7 &ndash; Local Declarations</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>
+<LI><A HREF="manual.html#3.4">3.4 &ndash; Expressions</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>
+<LI><A HREF="manual.html#3.4.1">3.4.1 &ndash; Arithmetic Operators</A>
+<LI><A HREF="manual.html#3.4.2">3.4.2 &ndash; Coercion</A>
+<LI><A HREF="manual.html#3.4.3">3.4.3 &ndash; Relational Operators</A>
+<LI><A HREF="manual.html#3.4.4">3.4.4 &ndash; Logical Operators</A>
+<LI><A HREF="manual.html#3.4.5">3.4.5 &ndash; Concatenation</A>
+<LI><A HREF="manual.html#3.4.6">3.4.6 &ndash; The Length Operator</A>
+<LI><A HREF="manual.html#3.4.7">3.4.7 &ndash; Precedence</A>
+<LI><A HREF="manual.html#3.4.8">3.4.8 &ndash; Table Constructors</A>
+<LI><A HREF="manual.html#3.4.9">3.4.9 &ndash; Function Calls</A>
+<LI><A HREF="manual.html#3.4.10">3.4.10 &ndash; Function Definitions</A>
 </UL>
-<LI><A HREF="manual.html#2.11">2.11 - Coroutines</A>
+<LI><A HREF="manual.html#3.5">3.5 &ndash; Visibility Rules</A>
 </UL>
 <P>
-<LI><A HREF="manual.html#3">3 - The Application Program Interface</A>
+<LI><A HREF="manual.html#4">4 &ndash; 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>
+<LI><A HREF="manual.html#4.1">4.1 &ndash; The Stack</A>
+<LI><A HREF="manual.html#4.2">4.2 &ndash; Stack Size</A>
+<LI><A HREF="manual.html#4.3">4.3 &ndash; Pseudo-Indices</A>
+<LI><A HREF="manual.html#4.4">4.4 &ndash; C Closures</A>
+<LI><A HREF="manual.html#4.5">4.5 &ndash; Registry</A>
+<LI><A HREF="manual.html#4.6">4.6 &ndash; Error Handling in C</A>
+<LI><A HREF="manual.html#4.7">4.7 &ndash; Handling Yields in C</A>
+<LI><A HREF="manual.html#4.8">4.8 &ndash; Functions and Types</A>
+<LI><A HREF="manual.html#4.9">4.9 &ndash; The Debug Interface</A>
 </UL>
 <P>
-<LI><A HREF="manual.html#4">4 - The Auxiliary Library</A>
+<LI><A HREF="manual.html#5">5 &ndash; The Auxiliary Library</A>
 <UL>
-<LI><A HREF="manual.html#4.1">4.1 - Functions and Types</A>
+<LI><A HREF="manual.html#5.1">5.1 &ndash; Functions and Types</A>
 </UL>
 <P>
-<LI><A HREF="manual.html#5">5 - Standard Libraries</A>
+<LI><A HREF="manual.html#6">6 &ndash; 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>
+<LI><A HREF="manual.html#6.1">6.1 &ndash; Basic Functions</A>
+<LI><A HREF="manual.html#6.2">6.2 &ndash; Coroutine Manipulation</A>
+<LI><A HREF="manual.html#6.3">6.3 &ndash; Modules</A>
+<LI><A HREF="manual.html#6.4">6.4 &ndash; String Manipulation</A>
 <UL>
-<LI><A HREF="manual.html#5.4.1">5.4.1 - Patterns</A>
+<LI><A HREF="manual.html#6.4.1">6.4.1 &ndash; 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>
+<LI><A HREF="manual.html#6.5">6.5 &ndash; Table Manipulation</A>
+<LI><A HREF="manual.html#6.6">6.6 &ndash; Mathematical Functions</A>
+<LI><A HREF="manual.html#6.7">6.7 &ndash; Bitwise Operations</A>
+<LI><A HREF="manual.html#6.8">6.8 &ndash; Input and Output Facilities</A>
+<LI><A HREF="manual.html#6.9">6.9 &ndash; Operating System Facilities</A>
+<LI><A HREF="manual.html#6.10">6.10 &ndash; The Debug Library</A>
 </UL>
 <P>
-<LI><A HREF="manual.html#6">6 - Lua Stand-alone</A>
+<LI><A HREF="manual.html#7">7 &ndash; Lua Standalone</A>
 <P>
-<LI><A HREF="manual.html#7">7 - Incompatibilities with the Previous Version</A>
+<LI><A HREF="manual.html#8">8 &ndash; 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>
+<LI><A HREF="manual.html#8.1">8.1 &ndash; Changes in the Language</A>
+<LI><A HREF="manual.html#8.2">8.2 &ndash; Changes in the Libraries</A>
+<LI><A HREF="manual.html#8.3">8.3 &ndash; Changes in the API</A>
 </UL>
 <P>
-<LI><A HREF="manual.html#8">8 - The Complete Syntax of Lua</A>
+<LI><A HREF="manual.html#9">9 &ndash; The Complete Syntax of Lua</A>
 </UL>
 
 <H2><A NAME="index">Index</A></H2>
@@ -158,63 +143,76 @@ Freely available under the terms of the
 <TR VALIGN="top">
 <TD>
 <H3><A NAME="functions">Lua functions</A></H3>
+<P>
 <A HREF="manual.html#pdf-_G">_G</A><BR>
 <A HREF="manual.html#pdf-_VERSION">_VERSION</A><BR>
+
+<P>
 <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-rawlen">rawlen</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-bit32.arshift">bit32.arshift</A><BR>
+<A HREF="manual.html#pdf-bit32.band">bit32.band</A><BR>
+<A HREF="manual.html#pdf-bit32.bnot">bit32.bnot</A><BR>
+<A HREF="manual.html#pdf-bit32.bor">bit32.bor</A><BR>
+<A HREF="manual.html#pdf-bit32.btest">bit32.btest</A><BR>
+<A HREF="manual.html#pdf-bit32.bxor">bit32.bxor</A><BR>
+<A HREF="manual.html#pdf-bit32.extract">bit32.extract</A><BR>
+<A HREF="manual.html#pdf-bit32.lrotate">bit32.lrotate</A><BR>
+<A HREF="manual.html#pdf-bit32.lshift">bit32.lshift</A><BR>
+<A HREF="manual.html#pdf-bit32.replace">bit32.replace</A><BR>
+<A HREF="manual.html#pdf-bit32.rrotate">bit32.rrotate</A><BR>
+<A HREF="manual.html#pdf-bit32.rshift">bit32.rshift</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>
 
+<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.getuservalue">debug.getuservalue</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.setuservalue">debug.setuservalue</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>
+<A HREF="manual.html#pdf-debug.upvalueid">debug.upvalueid</A><BR>
+<A HREF="manual.html#pdf-debug.upvaluejoin">debug.upvaluejoin</A><BR>
 
-</TD>
-<TD>
-<H3>&nbsp;</H3>
+<P>
 <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>
@@ -222,8 +220,8 @@ Freely available under the terms of the
 <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>
 
+<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>
@@ -238,8 +236,11 @@ Freely available under the terms of the
 <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>
 
+</TD>
+<TD>
+<H3>&nbsp;</H3>
+<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>
@@ -256,7 +257,6 @@ Freely available under the terms of the
 <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>
@@ -270,8 +270,8 @@ Freely available under the terms of the
 <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>
 
+<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>
@@ -283,17 +283,18 @@ Freely available under the terms of the
 <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>
 
+<P>
+<A HREF="manual.html#pdf-package.config">package.config</A><BR>
 <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-package.searchers">package.searchers</A><BR>
+<A HREF="manual.html#pdf-package.searchpath">package.searchpath</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>
@@ -308,17 +309,19 @@ Freely available under the terms of the
 <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>
 
+<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.pack">table.pack</A><BR>
 <A HREF="manual.html#pdf-table.remove">table.remove</A><BR>
 <A HREF="manual.html#pdf-table.sort">table.sort</A><BR>
+<A HREF="manual.html#pdf-table.unpack">table.unpack</A><BR>
 
 </TD>
 <TD>
 <H3>C API</H3>
+<P>
 <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>
@@ -327,22 +330,26 @@ Freely available under the terms of the
 <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_Unsigned">lua_Unsigned</A><BR>
 <A HREF="manual.html#lua_Writer">lua_Writer</A><BR>
-<P>
 
+<P>
+<A HREF="manual.html#lua_absindex">lua_absindex</A><BR>
+<A HREF="manual.html#lua_arith">lua_arith</A><BR>
 <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_callk">lua_callk</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_compare">lua_compare</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_copy">lua_copy</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_getctx">lua_getctx</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>
@@ -355,6 +362,7 @@ Freely available under the terms of the
 <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_getuservalue">lua_getuservalue</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>
@@ -368,15 +376,15 @@ Freely available under the terms of the
 <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_len">lua_len</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_pcallk">lua_pcallk</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>
@@ -395,6 +403,7 @@ Freely available under the terms of the
 <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_rawlen">lua_rawlen</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>
@@ -402,7 +411,6 @@ Freely available under the terms of the
 <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>
@@ -411,29 +419,39 @@ Freely available under the terms of the
 <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_setuservalue">lua_setuservalue</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_tointegerx">lua_tointegerx</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_tonumberx">lua_tonumberx</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_tounsigned">lua_tounsigned</A><BR>
+<A HREF="manual.html#lua_tounsignedx">lua_tounsignedx</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_upvalueid">lua_upvalueid</A><BR>
 <A HREF="manual.html#lua_upvalueindex">lua_upvalueindex</A><BR>
+<A HREF="manual.html#lua_upvaluejoin">lua_upvaluejoin</A><BR>
+<A HREF="manual.html#lua_version">lua_version</A><BR>
 <A HREF="manual.html#lua_xmove">lua_xmove</A><BR>
 <A HREF="manual.html#lua_yield">lua_yield</A><BR>
+<A HREF="manual.html#lua_yieldk">lua_yieldk</A><BR>
 
 </TD>
 <TD>
 <H3>auxiliary library</H3>
+<P>
 <A HREF="manual.html#luaL_Buffer">luaL_Buffer</A><BR>
 <A HREF="manual.html#luaL_Reg">luaL_Reg</A><BR>
-<P>
 
+<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>
@@ -442,6 +460,7 @@ Freely available under the terms of the
 <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_buffinitsize">luaL_buffinitsize</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>
@@ -454,15 +473,23 @@ Freely available under the terms of the
 <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_checkunsigned">luaL_checkunsigned</A><BR>
+<A HREF="manual.html#luaL_checkversion">luaL_checkversion</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_execresult">luaL_execresult</A><BR>
+<A HREF="manual.html#luaL_fileresult">luaL_fileresult</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_getsubtable">luaL_getsubtable</A><BR>
 <A HREF="manual.html#luaL_gsub">luaL_gsub</A><BR>
+<A HREF="manual.html#luaL_len">luaL_len</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_newlib">luaL_newlib</A><BR>
+<A HREF="manual.html#luaL_newlibtable">luaL_newlibtable</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>
@@ -472,27 +499,33 @@ Freely available under the terms of the
 <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_optunsigned">luaL_optunsigned</A><BR>
 <A HREF="manual.html#luaL_prepbuffer">luaL_prepbuffer</A><BR>
+<A HREF="manual.html#luaL_prepbuffsize">luaL_prepbuffsize</A><BR>
 <A HREF="manual.html#luaL_pushresult">luaL_pushresult</A><BR>
+<A HREF="manual.html#luaL_pushresultsize">luaL_pushresultsize</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_requiref">luaL_requiref</A><BR>
+<A HREF="manual.html#luaL_setfuncs">luaL_setfuncs</A><BR>
+<A HREF="manual.html#luaL_setmetatable">luaL_setmetatable</A><BR>
+<A HREF="manual.html#luaL_testudata">luaL_testudata</A><BR>
+<A HREF="manual.html#luaL_tolstring">luaL_tolstring</A><BR>
+<A HREF="manual.html#luaL_traceback">luaL_traceback</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>
+<SMALL CLASS="footer">
 Last update:
-Sat Jan 19 13:24:29 BRST 2008
+Tue Jun 28 14:53:13 BRT 2011
 </SMALL>
 <!--
-Last change: revised for Lua 5.1.3
+Last change: revised for Lua 5.2.0 (beta)
 -->
 
 </BODY>
diff --git a/doc/cover.png b/doc/cover.png
deleted file mode 100644
index 2dbb198..0000000
--- a/doc/cover.png
+++ /dev/null
diff --git a/doc/logo.gif b/doc/logo.gif
index 2f5e4ac..2f5e4ac 100644..100755
--- a/doc/logo.gif
+++ b/doc/logo.gif
diff --git a/doc/lua.1 b/doc/lua.1
deleted file mode 100644
index 24809cc..0000000
--- a/doc/lua.1
+++ /dev/null
@@ -1,163 +0,0 @@
-.\" $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/doc/lua.css b/doc/lua.css
index 039cf11..fb462d9 100644..100755
--- a/doc/lua.css
+++ b/doc/lua.css
@@ -2,16 +2,36 @@ body {
 	color: #000000 ;
 	background-color: #FFFFFF ;
 	font-family: sans-serif ;
+	font-family: Helvetica, Arial, sans-serif ;
 	text-align: justify ;
 	margin-right: 20px ;
 	margin-left: 20px ;
 }
 
 h1, h2, h3, h4 {
+	font-family: Verdana, Geneva, sans-serif ;
 	font-weight: normal ;
 	font-style: italic ;
 }
 
+h2 {
+	padding-top: 0.4em ;
+	padding-bottom: 0.4em ;
+	padding-left: 20px ;
+	margin-left: -20px ;
+	background-color: #E0E0FF ;
+}
+
+h3 {
+	padding-left: 8px ;
+	border-left: solid #E0E0FF 1em ;
+}
+
+table h3 {
+	padding-left: 0px ;
+	border-left: none ;
+}
+
 a:link {
 	color: #000080 ;
 	background-color: inherit ;
@@ -39,3 +59,26 @@ hr {
 	background-color: #a0a0a0 ;
 }
 
+:target {
+	background-color: #F8F8F8 ;
+	padding: 8px ;
+	border: solid #a0a0a0 2px ;
+}
+
+.footer {
+	color: gray ;
+	font-size: small ;
+}
+
+input[type=text] {
+	border: solid #a0a0a0 2px ;
+	border-radius: 2em ;
+	-moz-border-radius: 2em ;
+	background-image: url('images/search.png') ;
+	background-repeat: no-repeat;
+	background-position: left center ;
+	background-position: 4px center ;
+	padding-left: 20px ;
+	height: 2em ;
+}
+
diff --git a/doc/lua.html b/doc/lua.html
deleted file mode 100644
index 1d435ab..0000000
--- a/doc/lua.html
+++ /dev/null
@@ -1,172 +0,0 @@
-<!-- $Id: lua.man,v 1.11 2006/01/06 16:03:34 lhf Exp $ -->
-<HTML>
-<HEAD>
-<TITLE>LUA man page</TITLE>
-<LINK REL="stylesheet" TYPE="text/css" HREF="lua.css">
-</HEAD>
-
-<BODY BGCOLOR="#FFFFFF">
-
-<H2>NAME</H2>
-lua - Lua interpreter
-<H2>SYNOPSIS</H2>
-<B>lua</B>
-[
-<I>options</I>
-]
-[
-<I>script</I>
-[
-<I>args</I>
-]
-]
-<H2>DESCRIPTION</H2>
-<B>lua</B>
-is the stand-alone Lua interpreter.
-It loads and executes Lua programs,
-either in textual source form or
-in precompiled binary form.
-(Precompiled binaries are output by
-<B>luac</B>,
-the Lua compiler.)
-<B>lua</B>
-can be used as a batch interpreter and also interactively.
-<P>
-The given
-<I>options</I>
-(see below)
-are executed and then
-the Lua program in file
-<I>script</I>
-is loaded and executed.
-The given
-<I>args</I>
-are available to
-<I>script</I>
-as strings in a global table named
-<B>arg</B>.
-If these arguments contain spaces or other characters special to the shell,
-then they should be quoted
-(but note that the quotes will be removed by the shell).
-The arguments in
-<B>arg</B>
-start at 0,
-which contains the string
-'<I>script</I>'.
-The index of the last argument is stored in
-<B>arg.n</B>.
-The arguments given in the command line before
-<I>script</I>,
-including the name of the interpreter,
-are available in negative indices in
-<B>arg</B>.
-<P>
-At the very start,
-before even handling the command line,
-<B>lua</B>
-executes the contents of the environment variable
-<B>LUA_INIT</B>,
-if it is defined.
-If the value of
-<B>LUA_INIT</B>
-is of the form
-'@<I>filename</I>',
-then
-<I>filename</I>
-is executed.
-Otherwise, the string is assumed to be a Lua statement and is executed.
-<P>
-Options start with
-<B>'-'</B>
-and are described below.
-You can use
-<B>'--'</B>
-to signal the end of options.
-<P>
-If no arguments are given,
-then
-<B>"-v -i"</B>
-is assumed when the standard input is a terminal;
-otherwise,
-<B>"-"</B>
-is assumed.
-<P>
-In interactive mode,
-<B>lua</B>
-prompts the user,
-reads lines from the standard input,
-and executes them as they are read.
-If a line does not contain a complete statement,
-then a secondary prompt is displayed and
-lines are read until a complete statement is formed or
-a syntax error is found.
-So, one way to interrupt the reading of an incomplete statement is
-to force a syntax error:
-adding a
-<B>';'</B>
-in the middle of a statement is a sure way of forcing a syntax error
-(except inside multiline strings and comments; these must be closed explicitly).
-If a line starts with
-<B>'='</B>,
-then
-<B>lua</B>
-displays the values of all the expressions in the remainder of the
-line. The expressions must be separated by commas.
-The primary prompt is the value of the global variable
-<B>_PROMPT</B>,
-if this value is a string;
-otherwise, the default prompt is used.
-Similarly, the secondary prompt is the value of the global variable
-<B>_PROMPT2</B>.
-So,
-to change the prompts,
-set the corresponding variable to a string of your choice.
-You can do that after calling the interpreter
-or on the command line
-(but in this case you have to be careful with quotes
-if the prompt string contains a space; otherwise you may confuse the shell.)
-The default prompts are "&gt; " and "&gt;&gt; ".
-<H2>OPTIONS</H2>
-<P>
-<B>-</B>
-load and execute the standard input as a file,
-that is,
-not interactively,
-even when the standard input is a terminal.
-<P>
-<B>-e </B><I>stat</I>
-execute statement
-<I>stat</I>.
-You need to quote
-<I>stat </I>
-if it contains spaces, quotes,
-or other characters special to the shell.
-<P>
-<B>-i</B>
-enter interactive mode after
-<I>script</I>
-is executed.
-<P>
-<B>-l </B><I>name</I>
-call
-<B>require</B>('<I>name</I>')
-before executing
-<I>script</I>.
-Typically used to load libraries.
-<P>
-<B>-v</B>
-show version information.
-<H2>SEE ALSO</H2>
-<B>luac</B>(1)
-<BR>
-<A HREF="http://www.lua.org/">http://www.lua.org/</A>
-<H2>DIAGNOSTICS</H2>
-Error messages should be self explanatory.
-<H2>AUTHORS</H2>
-R. Ierusalimschy,
-L. H. de Figueiredo,
-and
-W. Celes
-<!-- EOF -->
-</BODY>
-</HTML>
diff --git a/doc/luac.1 b/doc/luac.1
deleted file mode 100644
index d814678..0000000
--- a/doc/luac.1
+++ /dev/null
@@ -1,136 +0,0 @@
-.\" $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/doc/luac.html b/doc/luac.html
deleted file mode 100644
index 179ffe8..0000000
--- a/doc/luac.html
+++ /dev/null
@@ -1,145 +0,0 @@
-<!-- $Id: luac.man,v 1.28 2006/01/06 16:03:34 lhf Exp $ -->
-<HTML>
-<HEAD>
-<TITLE>LUAC man page</TITLE>
-<LINK REL="stylesheet" TYPE="text/css" HREF="lua.css">
-</HEAD>
-
-<BODY BGCOLOR="#FFFFFF">
-
-<H2>NAME</H2>
-luac - Lua compiler
-<H2>SYNOPSIS</H2>
-<B>luac</B>
-[
-<I>options</I>
-] [
-<I>filenames</I>
-]
-<H2>DESCRIPTION</H2>
-<B>luac</B>
-is the Lua compiler.
-It translates programs written in the Lua programming language
-into binary files that can be later loaded and executed.
-<P>
-The main advantages of precompiling chunks are:
-faster loading,
-protecting source code from accidental user changes,
-and
-off-line syntax checking.
-<P>
-Precompiling does not imply faster execution
-because in Lua chunks are always compiled into bytecodes before being executed.
-<B>luac</B>
-simply allows those bytecodes to be saved in a file for later execution.
-<P>
-Precompiled chunks are not necessarily smaller than the corresponding source.
-The main goal in precompiling is faster loading.
-<P>
-The binary files created by
-<B>luac</B>
-are portable only among architectures with the same word size and byte order.
-<P>
-<B>luac</B>
-produces a single output file containing the bytecodes
-for all source files given.
-By default,
-the output file is named
-<B>luac.out</B>,
-but you can change this with the
-<B>-o</B>
-option.
-<P>
-In the command line,
-you can mix
-text files containing Lua source and
-binary files containing precompiled chunks.
-This is useful because several precompiled chunks,
-even from different (but compatible) platforms,
-can be combined into a single precompiled chunk.
-<P>
-You can use
-<B>'-'</B>
-to indicate the standard input as a source file
-and
-<B>'--'</B>
-to signal the end of options
-(that is,
-all remaining arguments will be treated as files even if they start with
-<B>'-'</B>).
-<P>
-The internal format of the binary files produced by
-<B>luac</B>
-is likely to change when a new version of Lua is released.
-So,
-save the source files of all Lua programs that you precompile.
-<P>
-<H2>OPTIONS</H2>
-Options must be separate.
-<P>
-<B>-l</B>
-produce a listing of the compiled bytecode for Lua's virtual machine.
-Listing bytecodes is useful to learn about Lua's virtual machine.
-If no files are given, then
-<B>luac</B>
-loads
-<B>luac.out</B>
-and lists its contents.
-<P>
-<B>-o </B><I>file</I>
-output to
-<I>file</I>,
-instead of the default
-<B>luac.out</B>.
-(You can use
-<B>'-'</B>
-for standard output,
-but not on platforms that open standard output in text mode.)
-The output file may be a source file because
-all files are loaded before the output file is written.
-Be careful not to overwrite precious files.
-<P>
-<B>-p</B>
-load files but do not generate any output file.
-Used mainly for syntax checking and for testing precompiled chunks:
-corrupted files will probably generate errors when loaded.
-Lua always performs a thorough integrity test on precompiled chunks.
-Bytecode that passes this test is completely safe,
-in the sense that it will not break the interpreter.
-However,
-there is no guarantee that such code does anything sensible.
-(None can be given, because the halting problem is unsolvable.)
-If no files are given, then
-<B>luac</B>
-loads
-<B>luac.out</B>
-and tests its contents.
-No messages are displayed if the file passes the integrity test.
-<P>
-<B>-s</B>
-strip debug information before writing the output file.
-This saves some space in very large chunks,
-but if errors occur when running a stripped chunk,
-then the error messages may not contain the full information they usually do.
-For instance,
-line numbers and names of local variables are lost.
-<P>
-<B>-v</B>
-show version information.
-<H2>FILES</H2>
-<P>
-<B>luac.out</B>
-default output file
-<H2>SEE ALSO</H2>
-<B>lua</B>(1)
-<BR>
-<A HREF="http://www.lua.org/">http://www.lua.org/</A>
-<H2>DIAGNOSTICS</H2>
-Error messages should be self explanatory.
-<H2>AUTHORS</H2>
-L. H. de Figueiredo,
-R. Ierusalimschy and
-W. Celes
-<!-- EOF -->
-</BODY>
-</HTML>
diff --git a/doc/manual.css b/doc/manual.css
index eed5afd..6d5a3f0 100644..100755
--- a/doc/manual.css
+++ b/doc/manual.css
@@ -11,3 +11,10 @@ span.apii {
 	font-family: inherit ;
 }
 
+p+h1, ul+h1 {
+	padding-top: 0.4em ;
+	padding-bottom: 0.4em ;
+	padding-left: 20px ;
+	margin-left: -20px ;
+	background-color: #E0E0FF ;
+}
diff --git a/doc/manual.html b/doc/manual.html
index f46f17c..7215565 100644..100755
--- a/doc/manual.html
+++ b/doc/manual.html
@@ -2,7 +2,7 @@
 <html>
 
 <head>
-<title>Lua 5.1 Reference Manual</title>
+<title>Lua 5.2 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">
@@ -13,13 +13,18 @@
 <hr>
 <h1>
 <a href="http://www.lua.org/"><img src="logo.gif" alt="" border="0"></a>
-Lua 5.1 Reference Manual
+Lua 5.2 Reference Manual
 </h1>
 
+<IMG SRC="alert.png" ALIGN="absbottom" ALT="[!]">
+<EM>This is a beta version of Lua 5.2.
+Some details may change in the final version.</EM>
+<P>
+
 by Roberto Ierusalimschy, Luiz Henrique de Figueiredo, Waldemar Celes
 <p>
 <small>
-Copyright &copy; 2006-2008 Lua.org, PUC-Rio.
+Copyright &copy; 2011 Lua.org, PUC-Rio.
 Freely available under the terms of the
 <a href="http://www.lua.org/license.html#5">Lua license</a>.
 </small>
@@ -33,12 +38,12 @@ Freely available under the terms of the
 <!-- ====================================================================== -->
 <p>
 
-<!-- $Id: manual.of,v 1.48 2008/08/18 15:24:20 roberto Exp $ -->
+<!-- $Id: manual.of,v 1.86 2011/07/08 20:00:45 roberto Exp $ -->
 
 
 
 
-<h1>1 - <a name="1">Introduction</a></h1>
+<h1>1 &ndash; <a name="1">Introduction</a></h1>
 
 <p>
 Lua is an extension programming language designed to support
@@ -48,22 +53,23 @@ It also offers good support for object-oriented programming,
 functional programming, and data-driven programming.
 Lua is intended to be used as a powerful, light-weight
 scripting language for any program that needs one.
-Lua is implemented as a library, written in <em>clean</em> C
-(that is, in the common subset of ANSI&nbsp;C and C++).
+Lua is implemented as a library, written in <em>clean C</em>,
+the common subset of Standard&nbsp;C and C++.
 
 
 <p>
 Being an extension language, Lua has no notion of a "main" program:
 it only works <em>embedded</em> in a host client,
 called the <em>embedding program</em> or simply the <em>host</em>.
-This host program can invoke functions to execute a piece of Lua code,
+The host program can invoke functions to execute a piece of Lua code,
 can write and read Lua variables,
 and can register C&nbsp;functions to be called by Lua code.
 Through the use of C&nbsp;functions, Lua can be augmented to cope with
 a wide range of different domains,
 thus creating customized programming languages sharing a syntactical framework.
 The Lua distribution includes a sample host program called <code>lua</code>,
-which uses the Lua library to offer a complete, stand-alone Lua interpreter.
+which uses the Lua library to offer a complete, standalone Lua interpreter,
+for interactive or batch use.
 
 
 <p>
@@ -80,11 +86,999 @@ 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>.
+see Roberto's book, <em>Programming in Lua</em> (second edition).
+
+
+
+<h1>2 &ndash; <a name="2">Basic Concepts</a></h1>
+
+<p>
+This section describes some basic concepts of the language.
+
+
+
+<h2>2.1 &ndash; <a name="2.1">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.
+Operations on numbers follow the same rules of
+the underlying C&nbsp;implementation,
+which, in turn, usually follows the IEEE 754 standard.
+(It is easy to build Lua interpreters that use other
+internal representations for numbers,
+such as single-precision floats or long integers;
+see file <code>luaconf.h</code>.)
+<em>String</em> represents immutable sequences of bytes.
+
+Lua is 8-bit clean:
+strings can contain any 8-bit value,
+including embedded zeros ('<code>\0</code>').
+
+
+<p>
+Lua can call (and manipulate) functions written in Lua and
+functions written in C
+(see <a href="#3.4.9">&sect;3.4.9</a>).
+
+
+<p>
+The type <em>userdata</em> is provided to allow arbitrary C&nbsp;data to
+be stored in Lua variables.
+This type corresponds to a block of raw memory
+and has no pre-defined operations in Lua,
+except assignment and identity test.
+However, by using <em>metatables</em>,
+the programmer can define operations for userdata values
+(see <a href="#2.4">&sect;2.4</a>).
+Userdata values cannot be created or modified in Lua,
+only through the C&nbsp;API.
+This guarantees the integrity of data owned by the host program.
+
+
+<p>
+The type <em>thread</em> represents independent threads of execution
+and it is used to implement coroutines (see <a href="#2.6">&sect;2.6</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 Lua value except <b>nil</b> and NaN
+(<em>Not a Number</em>, a special numeric value used to represent
+undefined or unrepresentable results, such as <code>0/0</code>).
+Tables can be <em>heterogeneous</em>;
+that is, they can contain values of all types (except <b>nil</b>).
+Any key with value <b>nil</b> is not considered part of the table.
+Conversely, any key that is not part of a table has
+an associated value <b>nil</b>.
+
+
+<p>
+Tables are the sole data structuring mechanism in Lua;
+they can be used to represent ordinary arrays, sequences,
+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="#3.4.8">&sect;3.4.8</a>).
+
+
+<p>
+We use the term <em>sequence</em> to denote a table where
+the set of all positive numeric keys is equal to <em>{1..n}</em>
+for some integer <em>n</em>,
+which is called the length of the sequence (see <a href="#3.4.6">&sect;3.4.6</a>).
+
+
+<p>
+Like indices,
+the value of a table field can be of any type.
+In particular,
+because functions are first-class values,
+table fields can contain functions.
+Thus tables can also carry <em>methods</em> (see <a href="#3.4.10">&sect;3.4.10</a>).
+
+
+<p>
+The indexing of tables follows
+the definition of raw equality in the language.
+The expressions <code>a[i]</code> and <code>a[j]</code>
+denote the same table element
+if and only if <code>i</code> and <code>j</code> are raw equal
+(that is, equal without metamethods).
+
+
+<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.
+
+
+
+
+
+<h2>2.2 &ndash; <a name="2.2">Environments and the Global Environment</a></h2>
+
+<p>
+As will be discussed in <a href="#3.2">&sect;3.2</a> and <a href="#3.3.3">&sect;3.3.3</a>,
+any reference to a global name <code>var</code> is syntactically translated
+to <code>_ENV.var</code>.
+Moreover, every chunk is compiled in the scope of an external
+variable called <code>_ENV</code> (see <a href="#3.3.2">&sect;3.3.2</a>),
+so <code>_ENV</code> itself is never a global name in a chunk.
+
+
+<p>
+Despite the existence of this external <code>_ENV</code> variable and
+the translation of global names,
+<code>_ENV</code> is a completely regular name.
+In particular,
+you can define new variables and parameters with that name.
+Each reference to a global name uses the <code>_ENV</code> that is
+visible at that point in the program,
+following the usual visibility rules of Lua.
+
+
+<p>
+Any table used as the value of <code>_ENV</code> is usually called
+an <em>environment</em>.
+
+
+<p>
+Lua keeps a distinguished environment called the <em>global environment</em>.
+This value is kept at a special index in the C registry (see <a href="#4.5">&sect;4.5</a>).
+In Lua, the variable <a href="#pdf-_G"><code>_G</code></a> is initialized with this same value.
+
+
+<p>
+When Lua compiles a chunk,
+it initializes the value of its <code>_ENV</code> variable
+with the global environment (see <a href="#pdf-load"><code>load</code></a>).
+Therefore, by default,
+global variables in Lua code refer to entries in the global environment.
+Moreover, all standard libraries are loaded in the global environment,
+and several functions there operate on that environment.
+You can use <a href="#pdf-load"><code>load</code></a> to load a chunk with a different environment.
+(In C, you have to load the chunk and then change the value
+of its first upvalue.)
+
+
+<p>
+If you change the global environment in the registry
+(through C code or the debug library),
+all chunks loaded after the change will get the new environment.
+Previously loaded chunks are not affected, however,
+as each has its own reference to the environment in its <code>_ENV</code> variable.
+Moreover, the variable <a href="#pdf-_G"><code>_G</code></a>
+(which is stored in the original global environment)
+is never updated by Lua.
+
+
+
+
+
+<h2>2.3 &ndash; <a name="2.3">Error Handling</a></h2>
+
+<p>
+Because Lua is an embedded extension language,
+all Lua actions start from C&nbsp;code in the host program
+calling a function from the Lua library (see <a href="#lua_pcall"><code>lua_pcall</code></a>).
+Whenever an error occurs during
+the compilation or execution of a Lua chunk,
+control returns to the host,
+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 <a href="#pdf-pcall"><code>pcall</code></a> or <a href="#pdf-xpcall"><code>xpcall</code></a>
+to call a given function in <em>protected mode</em>.
+
+
+<p>
+Whenever there is an error,
+an <em>error object</em> (also called an <em>error message</em>)
+is propagated with information about the error.
+Lua itself only generates errors where the error object is a string,
+but programs may generate errors with
+any value for the error object.
+
+
+<p>
+When you use <a href="#pdf-xpcall"><code>xpcall</code></a> or <a href="#lua_pcall"><code>lua_pcall</code></a>,
+you may give an <em>message handler</em>
+to be called in case of errors.
+This function is called with the original error message
+and returns a new error message.
+It is called before the error unwinds the stack,
+so that it can gather more information about the error,
+for instance by inspecting the stack and creating a stack traceback.
+This message handler is still protected by the protected call;
+so, an error inside the message handler
+will call the message handler again.
+If this loop goes on, Lua breaks it and returns an appropriate message.
+
+
+
+
+
+<h2>2.4 &ndash; <a name="2.4">Metatables and Metamethods</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>" of the value's metatable.
+If it finds one,
+Lua calls this function to perform the addition.
+
+
+<p>
+The keys in a metatable are derived from the <em>event</em> names;
+the corresponding values are called <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
+using the <a href="#pdf-getmetatable"><code>getmetatable</code></a> function.
+
+
+<p>
+You can replace the metatable of tables
+using 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&nbsp;API for that.
+
+
+<p>
+Tables and full userdata have individual metatables
+(although multiple tables and userdata can share their metatables).
+Values of all other types share one single metatable per type;
+that is, there is one single metatable for all numbers,
+one for all strings, etc.
+By default, a value has no metatable,
+but the string library sets a metatable for the string type (see <a href="#6.4">&sect;6.4</a>).
+
+
+<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.
+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>".
 
 
+<p>
+The semantics of these operations is better explained by a Lua function
+describing how the interpreter executes the operation.
+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="#6.1">&sect;6.1</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>).
+
+
+<p>
+For the unary <code>-</code> and <code>#</code> operators,
+the metamethod is called with a dummy second argument.
+This extra argument is only to simplify Lua's internals;
+it may be removed in future versions and therefore it is not present
+in the following code.
+(For most uses this extra argument is irrelevant.)
+
+
+
+<ul>
+
+<li><b>"add": </b>
+the <code>+</code> operation.
+
 
-<h1>2 - <a name="2">The Language</a></h1>
+
+<p>
+The function <code>getbinhandler</code> below defines how Lua chooses a handler
+for a binary operation.
+First, Lua tries the first operand.
+If its type does not define a handler for the operation,
+then Lua tries the second operand.
+
+<pre>
+     function getbinhandler (op1, op2, event)
+       return metatable(op1)[event] or metatable(op2)[event]
+     end
+</pre><p>
+By using this function,
+the behavior of the <code>op1 + op2</code> is
+
+<pre>
+     function add_event (op1, op2)
+       local o1, o2 = tonumber(op1), tonumber(op2)
+       if o1 and o2 then  -- both operands are numeric?
+         return o1 + o2   -- '+' here is the primitive 'add'
+       else  -- at least one of the operands is not numeric
+         local h = getbinhandler(op1, op2, "__add")
+         if h then
+           -- call the handler with both operands
+           return (h(op1, op2))
+         else  -- no handler available: default behavior
+           error(&middot;&middot;&middot;)
+         end
+       end
+     end
+</pre><p>
+</li>
+
+<li><b>"sub": </b>
+the <code>-</code> operation.
+
+Behavior similar to the "add" operation.
+</li>
+
+<li><b>"mul": </b>
+the <code>*</code> operation.
+
+Behavior similar to the "add" operation.
+</li>
+
+<li><b>"div": </b>
+the <code>/</code> operation.
+
+Behavior similar to the "add" operation.
+</li>
+
+<li><b>"mod": </b>
+the <code>%</code> operation.
+
+Behavior similar to the "add" operation,
+with the operation
+<code>o1 - floor(o1/o2)*o2</code> as the primitive operation.
+</li>
+
+<li><b>"pow": </b>
+the <code>^</code> (exponentiation) operation.
+
+Behavior similar to the "add" operation,
+with the function <code>pow</code> (from the C&nbsp;math library)
+as the primitive operation.
+</li>
+
+<li><b>"unm": </b>
+the unary <code>-</code> operation.
+
+
+<pre>
+     function unm_event (op)
+       local o = tonumber(op)
+       if o then  -- operand is numeric?
+         return -o  -- '-' here is the primitive 'unm'
+       else  -- the operand is not numeric.
+         -- Try to get a handler from the operand
+         local h = metatable(op).__unm
+         if h then
+           -- call the handler with the operand
+           return (h(op))
+         else  -- no handler available: default behavior
+           error(&middot;&middot;&middot;)
+         end
+       end
+     end
+</pre><p>
+</li>
+
+<li><b>"concat": </b>
+the <code>..</code> (concatenation) operation.
+
+
+<pre>
+     function concat_event (op1, op2)
+       if (type(op1) == "string" or type(op1) == "number") and
+          (type(op2) == "string" or type(op2) == "number") then
+         return op1 .. op2  -- primitive string concatenation
+       else
+         local h = getbinhandler(op1, op2, "__concat")
+         if h then
+           return (h(op1, op2))
+         else
+           error(&middot;&middot;&middot;)
+         end
+       end
+     end
+</pre><p>
+</li>
+
+<li><b>"len": </b>
+the <code>#</code> operation.
+
+
+<pre>
+     function len_event (op)
+       if type(op) == "string" then
+         return strlen(op)      -- primitive string length
+       else
+         local h = metatable(op).__len
+         if h then
+           return (h(op))       -- call handler with the operand
+         elseif type(op) == "table" then
+           return #op              -- primitive table length
+         else  -- no handler available: error
+           error(&middot;&middot;&middot;)
+         end
+       end
+     end
+</pre><p>
+See <a href="#3.4.6">&sect;3.4.6</a> for a description of the length of a table.
+</li>
+
+<li><b>"eq": </b>
+the <code>==</code> operation.
+
+The function <code>getequalhandler</code> defines how Lua chooses a metamethod
+for equality.
+A metamethod is selected only when both values
+being compared have the same type
+and the same metamethod for the selected operation.
+
+<pre>
+     function getequalhandler (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 values
+       end
+       if op1 == op2 then   -- primitive equal?
+         return true   -- values are equal
+       end
+       -- try metamethod
+       local h = getequalhandler(op1, op2, "__eq")
+       if h then
+         return (h(op1, op2))
+       else
+         return false
+       end
+     end
+</pre><p>
+</li>
+
+<li><b>"lt": </b>
+the <code>&lt;</code> operation.
+
+
+<pre>
+     function lt_event (op1, op2)
+       if type(op1) == "number" and type(op2) == "number" then
+         return op1 &lt; op2   -- numeric comparison
+       elseif type(op1) == "string" and type(op2) == "string" then
+         return op1 &lt; op2   -- lexicographic comparison
+       else
+         local h = getbinhandler(op1, op2, "__lt")
+         if h then
+           return (h(op1, op2))
+         else
+           error(&middot;&middot;&middot;)
+         end
+       end
+     end
+</pre><p>
+</li>
+
+<li><b>"le": </b>
+the <code>&lt;=</code> operation.
+
+
+<pre>
+     function le_event (op1, op2)
+       if type(op1) == "number" and type(op2) == "number" then
+         return op1 &lt;= op2   -- numeric comparison
+       elseif type(op1) == "string" and type(op2) == "string" then
+         return op1 &lt;= op2   -- lexicographic comparison
+       else
+         local h = getbinhandler(op1, op2, "__le")
+         if h then
+           return (h(op1, op2))
+         else
+           h = getbinhandler(op1, op2, "__lt")
+           if h then
+             return not h(op2, op1)
+           else
+             error(&middot;&middot;&middot;)
+           end
+         end
+       end
+     end
+</pre><p>
+Note that, in the absence of a "le" metamethod,
+Lua tries the "lt", assuming that <code>a &lt;= b</code> is
+equivalent to <code>not (b &lt; a)</code>.
+</li>
+
+<li><b>"index": </b>
+The indexing access <code>table[key]</code>.
+Note that the metamethod is tried only
+when <code>key</code> is not present in <code>table</code>.
+(When <code>table</code> is not a table,
+no key is ever present,
+so the metamethod is always tried.)
+
+
+<pre>
+     function gettable_event (table, key)
+       local h
+       if type(table) == "table" then
+         local v = rawget(table, key)
+         -- if key is present, return raw value
+         if v ~= nil then return v end
+         h = metatable(table).__index
+         if h == nil then return nil end
+       else
+         h = metatable(table).__index
+         if h == nil then
+           error(&middot;&middot;&middot;)
+         end
+       end
+       if type(h) == "function" then
+         return (h(table, key))     -- call the handler
+       else return h[key]           -- or repeat operation on it
+       end
+     end
+</pre><p>
+</li>
+
+<li><b>"newindex": </b>
+The indexing assignment <code>table[key] = value</code>.
+Note that the metamethod is tried only
+when <code>key</code> is not present in <code>table</code>.
+
+
+<pre>
+     function settable_event (table, key, value)
+       local h
+       if type(table) == "table" then
+         local v = rawget(table, key)
+         -- if key is present, do raw assignment
+         if v ~= nil then rawset(table, key, value); return end
+         h = metatable(table).__newindex
+         if h == nil then rawset(table, key, value); return end
+       else
+         h = metatable(table).__newindex
+         if h == nil then
+           error(&middot;&middot;&middot;)
+         end
+       end
+       if type(h) == "function" then
+         h(table, key,value)           -- call the handler
+       else h[key] = value             -- or repeat operation on it
+       end
+     end
+</pre><p>
+</li>
+
+<li><b>"call": </b>
+called when Lua calls a value.
+
+
+<pre>
+     function function_event (func, ...)
+       if type(func) == "function" then
+         return func(...)   -- primitive call
+       else
+         local h = metatable(func).__call
+         if h then
+           return h(func, ...)
+         else
+           error(&middot;&middot;&middot;)
+         end
+       end
+     end
+</pre><p>
+</li>
+
+</ul>
+
+
+
+
+<h2>2.5 &ndash; <a name="2.5">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> 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
+(e.g., 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 garbage-collector 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 is 200,
+which means that the collector runs at "twice"
+the speed of memory allocation.
+
+
+<p>
+If you set the step multiplier to a very large number
+(larger than 10% of the maximum number of
+bytes that the program may use),
+the collector behaves like a stop-the-world collector.
+If you then set the pause to 200,
+the collector behaves as in old Lua versions,
+doing a complete collection every time Lua doubles its
+memory usage.
+
+
+<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>2.5.1 &ndash; <a name="2.5.1">Garbage-Collection Metamethods</a></h3>
+
+<p>
+You can set garbage-collector metamethods for tables
+and, using the C&nbsp;API,
+for full userdata (see <a href="#2.4">&sect;2.4</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>
+For an object (table or userdata) to be finalized when collected,
+you must <em>mark</em> it for finalization.
+
+You mark an object for finalization when you set its metatable
+and the metatable has a field indexed by the string "<code>__gc</code>".
+Note that if you set a metatable without a <code>__gc</code> field
+and later create that field in the metatable,
+the object will not be marked for finalization.
+However, after an object is marked,
+you can freely change the <code>__gc</code> field of its metatable.
+
+
+<p>
+When a marked object becomes garbage,
+it is not collected immediately by the garbage collector.
+Instead, Lua puts it in a list.
+After the collection,
+Lua does the equivalent of the following function
+for each object in that list:
+
+<pre>
+     function gc_event (obj)
+       local h = metatable(obj).__gc
+       if type(h) == "function" then
+         h(obj)
+       end
+     end
+</pre>
+
+<p>
+At the end of each garbage-collection cycle,
+the finalizers for objects are called in
+the reverse order that they were marked for collection,
+among those collected in that cycle;
+that is, the first finalizer to be called is the one associated
+with the object marked last in the program.
+The execution of each finalizer may occur at any point during
+the execution of the regular code.
+
+
+<p>
+Because the object being collected must still be used by the finalizer 
+and even <em>resurrected</em>
+(e.g., stored by the finalizer in a global variable),
+the object memory is freed only when it becomes completely inaccessible
+(that is, in the next garbage-collection cycle unless it was resurrected).
+
+
+
+
+
+<h3>2.5.2 &ndash; <a name="2.5.2">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 that object.
+
+
+<p>
+A weak table can have weak keys, weak values, or both.
+A table with weak keys allows the collection of its keys,
+but prevents the collection of its values.
+A table with both weak keys and weak values allows the collection of
+both keys and values.
+In any case, if either the key or the value is collected,
+the whole pair is removed from the table.
+The weakness of a table is controlled by the
+<code>__mode</code> field of its metatable.
+If the <code>__mode</code> field is a string containing the character&nbsp;'<code>k</code>',
+the keys in the table are weak.
+If <code>__mode</code> contains '<code>v</code>',
+the values in the table are weak.
+
+
+<p>
+A table with weak keys and strong values
+is also called an <em>ephemeron table</em>.
+In an ephemeron table,
+a value is considered reachable only if its key is reachable.
+In particular,
+if the only reference to a key comes through its value,
+the pair is removed.
+
+
+<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.
+
+
+<p>
+Only objects that have an explicit construction
+can be removed from weak tables.
+Values, such as numbers and booleans,
+are not subject to garbage collection,
+and therefore are not removed from weak tables
+(unless its associated value is collected).
+Lua treats strings and light C functions as non-object values.
+
+
+<p>
+Objects marked for finalization have a special behavior in weak tables.
+When a marked object is a value in a weak table,
+it is removed from the table before running its finalizer.
+However, when it is a key,
+it is removed from the table only after running its finalizer.
+This behavior allows the finalizer to access properties
+associated with the object through weak tables.
+
+
+
+
+
+
+
+<h2>2.6 &ndash; <a name="2.6">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 by calling <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.
+
+
+<p>
+You execute a coroutine by calling <a href="#pdf-coroutine.resume"><code>coroutine.resume</code></a>.
+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 of how coroutines work,
+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>
+
+<p>
+You can also create and manipulate coroutines through the C API:
+see functions <a href="#lua_newthread"><code>lua_newthread</code></a>, <a href="#lua_resume"><code>lua_resume</code></a>,
+and <a href="#lua_yield"><code>lua_yield</code></a>.
+
+
+
+
+
+<h1>3 &ndash; <a name="3">The Language</a></h1>
 
 <p>
 This section describes the lexis, the syntax, and the semantics of Lua.
@@ -102,13 +1096,20 @@ in which
 [<em>a</em>]&nbsp;means an optional <em>a</em>.
 Non-terminals are shown like non-terminal,
 keywords are shown like <b>kword</b>,
-and other terminal symbols are shown like `<b>=</b>&acute;.
-The complete syntax of Lua can be found in <a href="#8">&sect;8</a>
+and other terminal symbols are shown like &lsquo;<b>=</b>&rsquo;.
+The complete syntax of Lua can be found in <a href="#9">&sect;9</a>
 at the end of this manual.
 
 
 
-<h2>2.1 - <a name="2.1">Lexical Conventions</a></h2>
+<h2>3.1 &ndash; <a name="3.1">Lexical Conventions</a></h2>
+
+<p>
+Lua is a free-form language.
+It ignores spaces (including new lines) and comments
+between lexical elements (tokens),
+except as delimiters between names and keywords.
+
 
 <p>
 <em>Names</em>
@@ -116,11 +1117,7 @@ at the end of this manual.
 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.
+Identifiers are used to name variables, table fields, and labels.
 
 
 <p>
@@ -129,10 +1126,10 @@ 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
+     and       break     do        else      elseif    end
+     false     for       function  goto      if        in
+     local     nil       not       or        repeat    return
+     then      true      until     while
 </pre>
 
 <p>
@@ -141,7 +1138,7 @@ Lua is a case-sensitive language:
 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.
+are reserved for variables used by Lua.
 
 
 <p>
@@ -150,7 +1147,7 @@ The following strings denote other tokens:
 <pre>
      +     -     *     /     %     ^     #
      ==    ~=    &lt;=    &gt;=    &lt;     &gt;     =
-     (     )     {     }     [     ]
+     (     )     {     }     [     ]     ::
      ;     :     ,     .     ..    ...
 </pre>
 
@@ -168,12 +1165,23 @@ and can contain the following C-like escape sequences:
 '<code>\\</code>' (backslash),
 '<code>\"</code>' (quotation mark [double quote]),
 and '<code>\'</code>' (apostrophe [single quote]).
-Moreover, a backslash followed by a real newline
+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>,
+The escape sequence '<code>\z</code>' skips the following span
+of white-space characters,
+including line breaks;
+it is particularly useful to break and indent a long string
+into multiple lines without adding the newlines and spaces
+into the string contents.
+
+
+<p>
+A character in a literal string can also be specified by its numerical value.
+This can be done with the escape sequence <code>\x<em>XX</em></code>,
+where <em>XX</em> is a sequence of exactly two hexadecimal digits,
+or with 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,
+(Note that if a decimal 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>'.
@@ -192,10 +1200,26 @@ A <em>closing long bracket</em> is defined similarly;
 for instance, a closing long bracket of level&nbsp;4 is written as <code>]====]</code>.
 A long string starts with an opening long bracket of any level and
 ends at the first closing long bracket of the same level.
+It can contain any text except a closing bracket of the proper 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.
+Any kind of end-of-line sequence
+(carriage return, newline, carriage return followed by newline,
+or newline followed by carriage return)
+is converted to a simple newline.
+
+
+<p>
+When parsing a from a string source,
+any byte in a literal string not
+explicitly affected by the previous rules represents itself.
+However, Lua opens files for parsing in text mode,
+and the system file functions may have problems with
+some control characters.
+So, it is safer to represent
+non-text data as a quoted literal with
+explicit escape sequences for non-text characters.
 
 
 <p>
@@ -219,14 +1243,19 @@ the five literal strings below denote the same string:
 </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>.
+A <em>numerical constant</em> can be written with an optional fractional part
+and an optional decimal exponent,
+marked by a letter '<code>e</code>' or '<code>E</code>'.
+Lua also accepts hexadecimal constants,
+which start with <code>0x</code> or <code>0X</code>.
+Hexadecimal constants also accept an optional fractional part
+plus an optional binary exponent,
+marked by a letter '<code>p</code>' or '<code>P</code>'.
 Examples of valid numerical constants are
 
 <pre>
-     3   3.0   3.1416   314.16e-2   0.31416E1   0xff   0x56
+     3     3.0     3.1416     314.16e-2     0.31416E1
+     0xff  0x0.1E  0xA23p-4   0X1.921FB54442D18P+1
 </pre>
 
 <p>
@@ -243,137 +1272,10 @@ 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">&sect;2.1</a>).
-
-
-<p>
-Lua can call (and manipulate) functions written in Lua and
-functions written in C
-(see <a href="#2.5.8">&sect;2.5.8</a>).
-
-
-<p>
-The type <em>userdata</em> is provided to allow arbitrary C&nbsp;data to
-be stored in Lua variables.
-This type corresponds to a block of raw memory
-and has no pre-defined operations in Lua,
-except assignment and identity test.
-However, by using <em>metatables</em>,
-the programmer can define operations for userdata values
-(see <a href="#2.8">&sect;2.8</a>).
-Userdata values cannot be created or modified in Lua,
-only through the C&nbsp;API.
-This guarantees the integrity of data owned by the host program.
-
-
-<p>
-The type <em>thread</em> represents independent threads of execution
-and it is used to implement coroutines (see <a href="#2.11">&sect;2.11</a>).
-Do not confuse Lua threads with operating-system threads.
-Lua supports coroutines on all systems,
-even those that do not support threads.
-
-
-<p>
-The type <em>table</em> implements associative arrays,
-that is, arrays that can be indexed not only with numbers,
-but with any value (except <b>nil</b>).
-Tables can be <em>heterogeneous</em>;
-that is, they can contain values of all types (except <b>nil</b>).
-Tables are the sole data structuring mechanism in Lua;
-they 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">&sect;2.5.7</a>).
-
-
-<p>
-Like indices,
-the value of a table field can be of any type (except <b>nil</b>).
-In particular,
-because functions are first-class values,
-table fields can contain functions.
-Thus tables can also carry <em>methods</em> (see <a href="#2.5.9">&sect;2.5.9</a>).
-
-
-<p>
-Tables, functions, threads, and (full) userdata values are <em>objects</em>:
-variables do not actually <em>contain</em> these values,
-only <em>references</em> to them.
-Assignment, parameter passing, and function returns
-always manipulate references to such values;
-these operations do not imply any kind of copy.
-
-
-<p>
-The library function <a href="#pdf-type"><code>type</code></a> returns a string describing the type
-of a given value.
-
-
-
-<h3>2.2.1 - <a name="2.2.1">Coercion</a></h3>
-
-<p>
-Lua provides automatic conversion between
-string and number values at run time.
-Any arithmetic operation applied to a string tries to convert
-this string to a number, following the usual conversion rules.
-Conversely, whenever a number is used where a string is expected,
-the number is converted to a string, in a reasonable format.
-For complete control over how numbers are converted to strings,
-use the <code>format</code> function from the string library
-(see <a href="#pdf-string.format"><code>string.format</code></a>).
-
-
-
-
-
-
-
-<h2>2.3 - <a name="2.3">Variables</a></h2>
+<h2>3.2 &ndash; <a name="3.2">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.
 
@@ -386,15 +1288,15 @@ which is a particular kind of local variable):
 <pre>
 	var ::= Name
 </pre><p>
-Name denotes identifiers, as defined in <a href="#2.1">&sect;2.1</a>.
+Name denotes identifiers, as defined in <a href="#3.1">&sect;3.1</a>.
 
 
 <p>
-Any variable is assumed to be global unless explicitly declared
-as a local (see <a href="#2.4.7">&sect;2.4.7</a>).
+Any variable name is assumed to be global unless explicitly declared
+as a local (see <a href="#3.3.7">&sect;3.3.7</a>).
 Local variables are <em>lexically scoped</em>:
 local variables can be freely accessed by functions
-defined inside their scope (see <a href="#2.6">&sect;2.6</a>).
+defined inside their scope (see <a href="#3.5">&sect;3.5</a>).
 
 
 <p>
@@ -405,13 +1307,12 @@ Before the first assignment to a variable, its value is <b>nil</b>.
 Square brackets are used to index a table:
 
 <pre>
-	var ::= prefixexp `<b>[</b>&acute; exp `<b>]</b>&acute;
+	var ::= prefixexp &lsquo;<b>[</b>&rsquo; exp &lsquo;<b>]</b>&rsquo;
 </pre><p>
-The meaning of accesses to global variables 
-and table fields can be changed via metatables.
+The meaning of accesses to table fields can be changed via metatables.
 An access to an indexed variable <code>t[i]</code> is equivalent to
 a call <code>gettable_event(t,i)</code>.
-(See <a href="#2.8">&sect;2.8</a> for a complete description of the
+(See <a href="#2.4">&sect;2.4</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.)
@@ -422,46 +1323,20 @@ The syntax <code>var.Name</code> is just syntactic sugar for
 <code>var["Name"]</code>:
 
 <pre>
-	var ::= prefixexp `<b>.</b>&acute; Name
+	var ::= prefixexp &lsquo;<b>.</b>&rsquo; Name
 </pre>
 
 <p>
-All global variables live as fields in ordinary Lua tables,
-called <em>environment tables</em> or simply
-<em>environments</em> (see <a href="#2.9">&sect;2.9</a>).
-Each function has its own reference to an environment,
-so that all global variables in this function
-will refer to this environment table.
-When a function is created,
-it inherits the environment from the function that created it.
-To get the environment table of a Lua function,
-you call <a href="#pdf-getfenv"><code>getfenv</code></a>.
-To replace it,
-you call <a href="#pdf-setfenv"><code>setfenv</code></a>.
-(You can only manipulate the environment of C&nbsp;functions
-through the debug library; (see <a href="#5.9">&sect;5.9</a>).)
-
-
-<p>
 An access to a global variable <code>x</code>
-is equivalent to <code>_env.x</code>,
-which in turn is equivalent to
+is equivalent to <code>_ENV.x</code>.
+Due to the way that chunks are compiled,
+<code>_ENV</code> is never a global name (see <a href="#2.2">&sect;2.2</a>).
 
-<pre>
-     gettable_event(_env, "x")
-</pre><p>
-where <code>_env</code> is the environment of the running function.
-(See <a href="#2.8">&sect;2.8</a> for a complete description of the
-<code>gettable_event</code> function.
-This function is not defined or callable in Lua.
-Similarly, the <code>_env</code> variable is not defined in Lua.
-We use them here only for explanatory purposes.)
 
 
 
 
-
-<h2>2.4 - <a name="2.4">Statements</a></h2>
+<h2>3.3 &ndash; <a name="3.3">Statements</a></h2>
 
 <p>
 Lua supports an almost conventional set of statements,
@@ -472,26 +1347,61 @@ and variable declarations.
 
 
 
-<h3>2.4.1 - <a name="2.4.1">Chunks</a></h3>
+<h3>3.3.1 &ndash; <a name="3.3.1">Blocks</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:
+A block is a list of statements,
+which are executed sequentially:
 
 <pre>
-	chunk ::= {stat [`<b>;</b>&acute;]}
+	block ::= {stat}
 </pre><p>
-There are no empty statements and thus '<code>;;</code>' is not legal.
+Lua has <em>empty statements</em>
+that allow you to separate statements with semicolons,
+start a block with a semicolon
+or write two semicolons in sequence:
 
+<pre>
+	stat ::= &lsquo;<b>;</b>&rsquo;
+</pre>
 
 <p>
-Lua handles a chunk as the body of an anonymous function 
+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> statement in the middle
+of another block (see <a href="#3.3.4">&sect;3.3.4</a>).
+
+
+
+
+
+<h3>3.3.2 &ndash; <a name="3.3.2">Chunks</a></h3>
+
+<p>
+The unit of execution of Lua is called a <em>chunk</em>.
+Syntactically,
+a chunk is simply a block:
+
+<pre>
+	chunk ::= block
+</pre>
+
+<p>
+Lua handles a chunk as the body of an anonymous function
 with a variable number of arguments
-(see <a href="#2.5.9">&sect;2.5.9</a>).
+(see <a href="#3.4.10">&sect;3.4.10</a>).
 As such, chunks can define local variables,
 receive arguments, and return values.
+Moreover, such anonymous function is compiled as in the
+scope of an external local variable called <code>_ENV</code> (see <a href="#2.2">&sect;2.2</a>).
+The resulting function always has <code>_ENV</code> as its only upvalue,
+even if it does not use that variable.
 
 
 <p>
@@ -513,31 +1423,7 @@ 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">&sect;2.4.4</a>).
-
-
-
-
-
-<h3>2.4.3 - <a name="2.4.3">Assignment</a></h3>
+<h3>3.3.3 &ndash; <a name="3.3.3">Assignment</a></h3>
 
 <p>
 Lua allows multiple assignments.
@@ -547,11 +1433,11 @@ and a list of expressions on the right side.
 The elements in both lists are separated by commas:
 
 <pre>
-	stat ::= varlist `<b>=</b>&acute; explist
-	varlist ::= var {`<b>,</b>&acute; var}
-	explist ::= exp {`<b>,</b>&acute; exp}
+	stat ::= varlist &lsquo;<b>=</b>&rsquo; explist
+	varlist ::= var {&lsquo;<b>,</b>&rsquo; var}
+	explist ::= exp {&lsquo;<b>,</b>&rsquo; exp}
 </pre><p>
-Expressions are discussed in <a href="#2.5">&sect;2.5</a>.
+Expressions are discussed in <a href="#3.4">&sect;3.4</a>.
 
 
 <p>
@@ -565,7 +1451,7 @@ 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">&sect;2.5</a>).
+(except when the call is enclosed in parentheses; see <a href="#3.4">&sect;3.4</a>).
 
 
 <p>
@@ -599,7 +1485,7 @@ The meaning of assignments to global variables
 and table fields can be changed via metatables.
 An assignment to an indexed variable <code>t[i] = val</code> is equivalent to
 <code>settable_event(t,i,val)</code>.
-(See <a href="#2.8">&sect;2.8</a> for a complete description of the
+(See <a href="#2.4">&sect;2.4</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.)
@@ -608,21 +1494,13 @@ 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.)
+<code>_ENV.x = val</code> (see <a href="#2.2">&sect;2.2</a>).
 
 
 
 
 
-<h3>2.4.4 - <a name="2.4.4">Control Structures</a></h3><p>
+<h3>3.3.4 &ndash; <a name="3.3.4">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:
@@ -635,7 +1513,7 @@ familiar syntax:
 	stat ::= <b>repeat</b> block <b>until</b> exp
 	stat ::= <b>if</b> exp <b>then</b> block {<b>elseif</b> exp <b>then</b> block} [<b>else</b> block] <b>end</b>
 </pre><p>
-Lua also has a <b>for</b> statement, in two flavors (see <a href="#2.4.5">&sect;2.4.5</a>).
+Lua also has a <b>for</b> statement, in two flavors (see <a href="#3.3.5">&sect;3.3.5</a>).
 
 
 <p>
@@ -655,18 +1533,34 @@ 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).
+The <b>goto</b> statement transfers the program control to a label.
+For syntactical reasons,
+labels in Lua are considered statements too:
+
 
-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]
+	stat ::= <b>goto</b> Name
+	stat ::= label
+	label ::= &lsquo;<b>::</b>&rsquo; Name &lsquo;<b>::</b>&rsquo;
 </pre>
 
 <p>
-The <b>break</b> statement is used to terminate the execution of a
+A label is visible in the entire block where it is defined,
+except
+inside nested blocks where a label with the same name is defined and
+inside nested functions.
+A goto may jump to any visible label as long as it does not
+enter into the scope of a local variable.
+
+
+<p>
+Both labels and empty statements are called <em>void statements</em>,
+as they perform no actions.
+
+
+<p>
+The <b>break</b> statement terminates the execution of a
 <b>while</b>, <b>repeat</b>, or <b>for</b> loop,
 skipping to the next statement after the loop:
 
@@ -678,21 +1572,29 @@ 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,
+The <b>return</b> statement is used to return values
+from a function or a chunk (which is a function in disguise).
+
+Functions can return more than one value,
+so the syntax for the <b>return</b> statement is
+
+<pre>
+	stat ::= <b>return</b> [explist] [&lsquo;<b>;</b>&rsquo;]
+</pre>
+
+<p>
+The <b>return</b> statement can only be written
+as the last statement of a block.
+If it is really necessary to <b>return</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.
+as in the idiom <code>do return end</code>,
+because now <b>return</b> is the last statement in its (inner) block.
 
 
 
 
 
-<h3>2.4.5 - <a name="2.4.5">For Statement</a></h3>
+<h3>3.3.5 &ndash; <a name="3.3.5">For Statement</a></h3>
 
 <p>
 
@@ -706,7 +1608,7 @@ control variable runs through an arithmetic progression.
 It has the following syntax:
 
 <pre>
-	stat ::= <b>for</b> Name `<b>=</b>&acute; exp `<b>,</b>&acute; exp [`<b>,</b>&acute; exp] <b>do</b> block <b>end</b>
+	stat ::= <b>for</b> Name &lsquo;<b>=</b>&rsquo; exp &lsquo;<b>,</b>&rsquo; exp [&lsquo;<b>,</b>&rsquo; 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
@@ -771,7 +1673,7 @@ The generic <b>for</b> loop has the following syntax:
 
 <pre>
 	stat ::= <b>for</b> namelist <b>in</b> explist <b>do</b> block <b>end</b>
-	namelist ::= Name {`<b>,</b>&acute; Name}
+	namelist ::= Name {&lsquo;<b>,</b>&rsquo; Name}
 </pre><p>
 A <b>for</b> statement like
 
@@ -785,8 +1687,8 @@ is equivalent to the code:
        local <em>f</em>, <em>s</em>, <em>var</em> = <em>explist</em>
        while true do
          local <em>var_1</em>, &middot;&middot;&middot;, <em>var_n</em> = <em>f</em>(<em>s</em>, <em>var</em>)
+         if <em>var_1</em> == nil then break end
          <em>var</em> = <em>var_1</em>
-         if <em>var</em> == nil then break end
          <em>block</em>
        end
      end
@@ -823,7 +1725,7 @@ then assign them to other variables before breaking or exiting the loop.
 
 
 
-<h3>2.4.6 - <a name="2.4.6">Function Calls as Statements</a></h3><p>
+<h3>3.3.6 &ndash; <a name="3.3.6">Function Calls as Statements</a></h3><p>
 To allow possible side-effects,
 function calls can be executed as statements:
 
@@ -831,32 +1733,31 @@ function calls can be executed as statements:
 	stat ::= functioncall
 </pre><p>
 In this case, all returned values are thrown away.
-Function calls are explained in <a href="#2.5.8">&sect;2.5.8</a>.
+Function calls are explained in <a href="#3.4.9">&sect;3.4.9</a>.
 
 
 
 
 
-<h3>2.4.7 - <a name="2.4.7">Local Declarations</a></h3><p>
+<h3>3.3.7 &ndash; <a name="3.3.7">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>&acute; explist]
+	stat ::= <b>local</b> namelist [&lsquo;<b>=</b>&rsquo; explist]
 </pre><p>
 If present, an initial assignment has the same semantics
-of a multiple assignment (see <a href="#2.4.3">&sect;2.4.3</a>).
+of a multiple assignment (see <a href="#3.3.3">&sect;3.3.3</a>).
 Otherwise, all variables are initialized with <b>nil</b>.
 
 
 <p>
-A chunk is also a block (see <a href="#2.4.1">&sect;2.4.1</a>),
+A chunk is also a block (see <a href="#3.3.2">&sect;3.3.2</a>),
 and so local variables can be declared in a chunk outside any explicit block.
-The scope of such local variables extends until the end of the chunk.
 
 
 <p>
-The visibility rules for local variables are explained in <a href="#2.6">&sect;2.6</a>.
+The visibility rules for local variables are explained in <a href="#3.5">&sect;3.5</a>.
 
 
 
@@ -864,7 +1765,7 @@ The visibility rules for local variables are explained in <a href="#2.6">&sect;2
 
 
 
-<h2>2.5 - <a name="2.5">Expressions</a></h2>
+<h2>3.4 &ndash; <a name="3.4">Expressions</a></h2>
 
 <p>
 The basic expressions in Lua are the following:
@@ -874,39 +1775,39 @@ The basic expressions in Lua are the following:
 	exp ::= <b>nil</b> | <b>false</b> | <b>true</b>
 	exp ::= Number
 	exp ::= String
-	exp ::= function
+	exp ::= functiondef
 	exp ::= tableconstructor
-	exp ::= `<b>...</b>&acute;
+	exp ::= &lsquo;<b>...</b>&rsquo;
 	exp ::= exp binop exp
 	exp ::= unop exp
-	prefixexp ::= var | functioncall | `<b>(</b>&acute; exp `<b>)</b>&acute;
+	prefixexp ::= var | functioncall | &lsquo;<b>(</b>&rsquo; exp &lsquo;<b>)</b>&rsquo;
 </pre>
 
 <p>
-Numbers and literal strings are explained in <a href="#2.1">&sect;2.1</a>;
-variables are explained in <a href="#2.3">&sect;2.3</a>;
-function definitions are explained in <a href="#2.5.9">&sect;2.5.9</a>;
-function calls are explained in <a href="#2.5.8">&sect;2.5.8</a>;
-table constructors are explained in <a href="#2.5.7">&sect;2.5.7</a>.
+Numbers and literal strings are explained in <a href="#3.1">&sect;3.1</a>;
+variables are explained in <a href="#3.2">&sect;3.2</a>;
+function definitions are explained in <a href="#3.4.10">&sect;3.4.10</a>;
+function calls are explained in <a href="#3.4.9">&sect;3.4.9</a>;
+table constructors are explained in <a href="#3.4.8">&sect;3.4.8</a>.
 Vararg expressions,
 denoted by three dots ('<code>...</code>'), can only be used when
 directly inside a vararg function;
-they are explained in <a href="#2.5.9">&sect;2.5.9</a>.
+they are explained in <a href="#3.4.10">&sect;3.4.10</a>.
 
 
 <p>
-Binary operators comprise arithmetic operators (see <a href="#2.5.1">&sect;2.5.1</a>),
-relational operators (see <a href="#2.5.2">&sect;2.5.2</a>), logical operators (see <a href="#2.5.3">&sect;2.5.3</a>),
-and the concatenation operator (see <a href="#2.5.4">&sect;2.5.4</a>).
-Unary operators comprise the unary minus (see <a href="#2.5.1">&sect;2.5.1</a>),
-the unary <b>not</b> (see <a href="#2.5.3">&sect;2.5.3</a>),
-and the unary <em>length operator</em> (see <a href="#2.5.5">&sect;2.5.5</a>).
+Binary operators comprise arithmetic operators (see <a href="#3.4.1">&sect;3.4.1</a>),
+relational operators (see <a href="#3.4.3">&sect;3.4.3</a>), logical operators (see <a href="#3.4.4">&sect;3.4.4</a>),
+and the concatenation operator (see <a href="#3.4.5">&sect;3.4.5</a>).
+Unary operators comprise the unary minus (see <a href="#3.4.1">&sect;3.4.1</a>),
+the unary <b>not</b> (see <a href="#3.4.4">&sect;3.4.4</a>),
+and the unary <em>length operator</em> (see <a href="#3.4.6">&sect;3.4.6</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">&sect;2.4.6</a>)),
+(only possible for function calls (see <a href="#3.3.6">&sect;3.3.6</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
@@ -950,14 +1851,14 @@ 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>
+<h3>3.4.1 &ndash; <a name="3.4.1">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).
+and unary <code>-</code> (mathematical negation).
 If the operands are numbers, or strings that can be converted to
-numbers (see <a href="#2.2.1">&sect;2.2.1</a>),
+numbers (see <a href="#3.4.2">&sect;3.4.2</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>.
@@ -973,7 +1874,26 @@ the quotient towards minus infinity.
 
 
 
-<h3>2.5.2 - <a name="2.5.2">Relational Operators</a></h3><p>
+<h3>3.4.2 &ndash; <a name="3.4.2">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 rules of the Lua lexer.
+(The string may have leading and trailing spaces,
+plus an optional sign.)
+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>).
+
+
+
+
+
+<h3>3.4.3 &ndash; <a name="3.4.3">Relational Operators</a></h3><p>
 The relational operators in Lua are
 
 <pre>
@@ -987,22 +1907,25 @@ 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.
+Tables, userdata, and threads
+are compared by reference:
+two objects are considered equal only if they are the same object.
 Every time you create a new object
-(a table, userdata, thread, or function),
+(a table, userdata, or thread),
 this new object is different from any previously existing object.
+Closures with the same reference are always equal.
+Closures with any detectable difference
+(different behavior, different definition) are always different.
 
 
 <p>
-You can change the way that Lua compares tables and userdata 
-by using the "eq" metamethod (see <a href="#2.8">&sect;2.8</a>).
+You can change the way that Lua compares tables and userdata
+by using the "eq" metamethod (see <a href="#2.4">&sect;2.4</a>).
 
 
 <p>
-The conversion rules of <a href="#2.2.1">&sect;2.2.1</a>
-<em>do not</em> apply to equality comparisons.
+The conversion rules of <a href="#3.4.2">&sect;3.4.2</a>
+do not 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.
@@ -1018,7 +1941,7 @@ If both arguments are numbers, then they are compared as such.
 Otherwise, if both arguments are strings,
 then their values are compared according to the current locale.
 Otherwise, Lua tries to call the "lt" or the "le"
-metamethod (see <a href="#2.8">&sect;2.8</a>).
+metamethod (see <a href="#2.4">&sect;2.4</a>).
 A comparison <code>a &gt; b</code> is translated to <code>b &lt; a</code>
 and <code>a &gt;= b</code> is translated to <code>b &lt;= a</code>.
 
@@ -1026,10 +1949,10 @@ and <code>a &gt;= b</code> is translated to <code>b &lt;= a</code>.
 
 
 
-<h3>2.5.3 - <a name="2.5.3">Logical Operators</a></h3><p>
+<h3>3.4.4 &ndash; <a name="3.4.4">Logical Operators</a></h3><p>
 The logical operators in Lua are
 <b>and</b>, <b>or</b>, and <b>not</b>.
-Like the control structures (see <a href="#2.4.4">&sect;2.4.4</a>),
+Like the control structures (see <a href="#3.3.4">&sect;3.3.4</a>),
 all logical operators consider both <b>false</b> and <b>nil</b> as false
 and anything else as true.
 
@@ -1064,46 +1987,56 @@ Here are some examples:
 
 
 
-<h3>2.5.4 - <a name="2.5.4">Concatenation</a></h3><p>
+<h3>3.4.5 &ndash; <a name="3.4.5">Concatenation</a></h3><p>
 The string concatenation operator in Lua is
 denoted by two dots ('<code>..</code>').
 If both operands are strings or numbers, then they are converted to
-strings according to the rules mentioned in <a href="#2.2.1">&sect;2.2.1</a>.
-Otherwise, the "concat" metamethod is called (see <a href="#2.8">&sect;2.8</a>).
+strings according to the rules mentioned in <a href="#3.4.2">&sect;3.4.2</a>.
+Otherwise, the "concat" metamethod is called (see <a href="#2.4">&sect;2.4</a>).
 
 
 
 
 
-<h3>2.5.5 - <a name="2.5.5">The Length Operator</a></h3>
+<h3>3.4.6 &ndash; <a name="3.4.6">The Length Operator</a></h3>
 
 <p>
-The length operator is denoted by the unary operator <code>#</code>.
+The length operator is denoted by the unary prefix 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). 
+A program can modify the behavior of the length operator for
+any value but strings through the <code>__len</code> metamethod (see <a href="#2.4">&sect;2.4</a>).
 
 
+<p>
+Unless a <code>__len</code> metamethod is given,
+the length of a table <code>t</code> is only defined if the
+table is a <em>sequence</em>,
+that is,
+the set of its positive numeric keys is equal to <em>{1..n}</em>
+for some integer <em>n</em>.
+In that case, <em>n</em> is its length.
+Note that a table like
+
+<pre>
+     {10, 20, nil, 40}
+</pre><p>
+is not a sequence, because it has the key <code>4</code>
+but does not have the key <code>3</code>.
+(So, there is no <em>n</em> such that the set <em>{1..n}</em> is equal
+to the set of positive numeric keys of that table.)
+Note, however, that non-numeric keys do not interfere
+with whether a table is a sequence.
 
 
 
-<h3>2.5.6 - <a name="2.5.6">Precedence</a></h3><p>
+
+
+<h3>3.4.7 &ndash; <a name="3.4.7">Precedence</a></h3><p>
 Operator precedence in Lua follows the table below,
 from lower to higher priority:
 
@@ -1127,7 +2060,7 @@ All other binary operators are left associative.
 
 
 
-<h3>2.5.7 - <a name="2.5.7">Table Constructors</a></h3><p>
+<h3>3.4.8 &ndash; <a name="3.4.8">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
@@ -1135,10 +2068,10 @@ or to create a table and initialize some of its fields.
 The general syntax for constructors is
 
 <pre>
-	tableconstructor ::= `<b>{</b>&acute; [fieldlist] `<b>}</b>&acute;
+	tableconstructor ::= &lsquo;<b>{</b>&rsquo; [fieldlist] &lsquo;<b>}</b>&rsquo;
 	fieldlist ::= field {fieldsep field} [fieldsep]
-	field ::= `<b>[</b>&acute; exp `<b>]</b>&acute; `<b>=</b>&acute; exp | Name `<b>=</b>&acute; exp | exp
-	fieldsep ::= `<b>,</b>&acute; | `<b>;</b>&acute;
+	field ::= &lsquo;<b>[</b>&rsquo; exp &lsquo;<b>]</b>&rsquo; &lsquo;<b>=</b>&rsquo; exp | Name &lsquo;<b>=</b>&rsquo; exp | exp
+	fieldsep ::= &lsquo;<b>,</b>&rsquo; | &lsquo;<b>;</b>&rsquo;
 </pre>
 
 <p>
@@ -1175,10 +2108,7 @@ is equivalent to
 If the last field in the list has the form <code>exp</code>
 and the expression is a function call or a vararg expression,
 then all values returned by this expression enter the list consecutively
-(see <a href="#2.5.8">&sect;2.5.8</a>).
-To avoid this,
-enclose the function call or the vararg expression
-in parentheses (see <a href="#2.5">&sect;2.5</a>).
+(see <a href="#3.4.9">&sect;3.4.9</a>).
 
 
 <p>
@@ -1189,7 +2119,7 @@ as a convenience for machine-generated code.
 
 
 
-<h3>2.5.8 - <a name="2.5.8">Function Calls</a></h3><p>
+<h3>3.4.9 &ndash; <a name="3.4.9">Function Calls</a></h3><p>
 A function call in Lua has the following syntax:
 
 <pre>
@@ -1203,14 +2133,14 @@ with the given arguments.
 Otherwise, the prefixexp "call" metamethod is called,
 having as first parameter the value of prefixexp,
 followed by the original call arguments
-(see <a href="#2.8">&sect;2.8</a>).
+(see <a href="#2.4">&sect;2.4</a>).
 
 
 <p>
 The form
 
 <pre>
-	functioncall ::= prefixexp `<b>:</b>&acute; Name args
+	functioncall ::= prefixexp &lsquo;<b>:</b>&rsquo; Name args
 </pre><p>
 can be used to call "methods".
 A call <code>v:name(<em>args</em>)</code>
@@ -1222,7 +2152,7 @@ except that <code>v</code> is evaluated only once.
 Arguments have the following syntax:
 
 <pre>
-	args ::= `<b>(</b>&acute; [explist] `<b>)</b>&acute;
+	args ::= &lsquo;<b>(</b>&rsquo; [explist] &lsquo;<b>)</b>&rsquo;
 	args ::= tableconstructor
 	args ::= String
 </pre><p>
@@ -1237,23 +2167,7 @@ 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 call of the form <code>return <em>functioncall</em></code> is called
 a <em>tail call</em>.
 Lua implements <em>proper tail calls</em>
 (or <em>proper tail recursion</em>):
@@ -1280,14 +2194,14 @@ So, none of the following examples are tail calls:
 
 
 
-<h3>2.5.9 - <a name="2.5.9">Function Definitions</a></h3>
+<h3>3.4.10 &ndash; <a name="3.4.10">Function Definitions</a></h3>
 
 <p>
 The syntax for function definition is
 
 <pre>
-	function ::= <b>function</b> funcbody
-	funcbody ::= `<b>(</b>&acute; [parlist] `<b>)</b>&acute; block <b>end</b>
+	functiondef ::= <b>function</b> funcbody
+	funcbody ::= &lsquo;<b>(</b>&rsquo; [parlist] &lsquo;<b>)</b>&rsquo; block <b>end</b>
 </pre>
 
 <p>
@@ -1296,7 +2210,7 @@ The following syntactic sugar simplifies function definitions:
 <pre>
 	stat ::= <b>function</b> funcname funcbody
 	stat ::= <b>local</b> <b>function</b> Name funcbody
-	funcname ::= Name {`<b>.</b>&acute; Name} [`<b>:</b>&acute; Name]
+	funcname ::= Name {&lsquo;<b>.</b>&rsquo; Name} [&lsquo;<b>:</b>&rsquo; Name]
 </pre><p>
 The statement
 
@@ -1328,7 +2242,7 @@ translates to
 <pre>
      local f; f = function () <em>body</em> end
 </pre><p>
-<em>not</em> to
+not to
 
 <pre>
      local f = function () <em>body</em> end
@@ -1346,9 +2260,6 @@ 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>
@@ -1356,7 +2267,7 @@ Parameters act as local variables that are
 initialized with the argument values:
 
 <pre>
-	parlist ::= namelist [`<b>,</b>&acute; `<b>...</b>&acute;] | `<b>...</b>&acute;
+	parlist ::= namelist [&lsquo;<b>,</b>&rsquo; &lsquo;<b>...</b>&rsquo;] | &lsquo;<b>...</b>&rsquo;
 </pre><p>
 When a function is called,
 the list of arguments is adjusted to
@@ -1405,13 +2316,20 @@ to the vararg expression:
 </pre>
 
 <p>
-Results are returned using the <b>return</b> statement (see <a href="#2.4.4">&sect;2.4.4</a>).
+Results are returned using the <b>return</b> statement (see <a href="#3.3.4">&sect;3.3.4</a>).
 If control reaches the end of a function
 without encountering a <b>return</b> statement,
 then the function returns with no results.
 
 
 <p>
+
+There is a system-dependent limit on the number of values
+that a function may return.
+This limit is guaranteed to be larger than 1000.
+
+
+<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>.
@@ -1431,14 +2349,14 @@ is syntactic sugar for
 
 
 
-<h2>2.6 - <a name="2.6">Visibility Rules</a></h2>
+<h2>3.5 &ndash; <a name="3.5">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.
+The scope of a local variable begins at the first statement after
+its declaration and lasts until the last non-void statement
+of the innermost block that includes the declaration.
 Consider the following example:
 
 <pre>
@@ -1493,745 +2411,7 @@ while all of them share the same <code>x</code>.
 
 
 
-<h2>2.7 - <a name="2.7">Error Handling</a></h2>
-
-<p>
-Because Lua is an embedded extension language,
-all Lua actions start from C&nbsp;code in the host program
-calling a function from the Lua library (see <a href="#lua_pcall"><code>lua_pcall</code></a>).
-Whenever an error occurs during Lua compilation or execution,
-control returns to C,
-which can take appropriate measures
-(such as printing an error message).
-
-
-<p>
-Lua code can explicitly generate an error by calling the
-<a href="#pdf-error"><code>error</code></a> function.
-If you need to catch errors in Lua,
-you can use the <a href="#pdf-pcall"><code>pcall</code></a> function.
-
-
-
-
-
-<h2>2.8 - <a name="2.8">Metatables</a></h2>
-
-<p>
-Every value in Lua 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&nbsp;API for that.
-
-
-<p>
-Tables and full userdata have individual metatables
-(although multiple tables and userdata can share their metatables).
-Values of all other types share one single metatable per type;
-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">&sect;5.1</a>.
-In particular, to retrieve the metamethod of a given object,
-we use the expression
-
-<pre>
-     metatable(obj)[event]
-</pre><p>
-This should be read as
-
-<pre>
-     rawget(getmetatable(obj) or {}, event)
-</pre><p>
-
-That is, the access to a metamethod does not invoke other metamethods,
-and the access to objects with no metatables does not fail
-(it simply results in <b>nil</b>).
-
-
-
-<ul>
-
-<li><b>"add":</b>
-the <code>+</code> operation.
-
-
-
-<p>
-The function <code>getbinhandler</code> below defines how Lua chooses a handler
-for a binary operation.
-First, Lua tries the first operand.
-If its type does not define a handler for the operation,
-then Lua tries the second operand.
-
-<pre>
-     function getbinhandler (op1, op2, event)
-       return metatable(op1)[event] or metatable(op2)[event]
-     end
-</pre><p>
-By using this function,
-the behavior of the <code>op1 + op2</code> is
-
-<pre>
-     function add_event (op1, op2)
-       local o1, o2 = tonumber(op1), tonumber(op2)
-       if o1 and o2 then  -- both operands are numeric?
-         return o1 + o2   -- '+' here is the primitive 'add'
-       else  -- at least one of the operands is not numeric
-         local h = getbinhandler(op1, op2, "__add")
-         if h then
-           -- call the handler with both operands
-           return (h(op1, op2))
-         else  -- no handler available: default behavior
-           error(&middot;&middot;&middot;)
-         end
-       end
-     end
-</pre><p>
-</li>
-
-<li><b>"sub":</b>
-the <code>-</code> operation.
-
-Behavior similar to the "add" operation.
-</li>
-
-<li><b>"mul":</b>
-the <code>*</code> operation.
-
-Behavior similar to the "add" operation.
-</li>
-
-<li><b>"div":</b>
-the <code>/</code> operation.
-
-Behavior similar to the "add" operation.
-</li>
-
-<li><b>"mod":</b>
-the <code>%</code> operation.
-
-Behavior similar to the "add" operation,
-with the operation
-<code>o1 - floor(o1/o2)*o2</code> as the primitive operation.
-</li>
-
-<li><b>"pow":</b>
-the <code>^</code> (exponentiation) operation.
-
-Behavior similar to the "add" operation,
-with the function <code>pow</code> (from the C&nbsp;math library)
-as the primitive operation.
-</li>
-
-<li><b>"unm":</b>
-the unary <code>-</code> operation.
-
-
-<pre>
-     function unm_event (op)
-       local o = tonumber(op)
-       if o then  -- operand is numeric?
-         return -o  -- '-' here is the primitive 'unm'
-       else  -- the operand is not numeric.
-         -- Try to get a handler from the operand
-         local h = metatable(op).__unm
-         if h then
-           -- call the handler with the operand
-           return (h(op))
-         else  -- no handler available: default behavior
-           error(&middot;&middot;&middot;)
-         end
-       end
-     end
-</pre><p>
-</li>
-
-<li><b>"concat":</b>
-the <code>..</code> (concatenation) operation.
-
-
-<pre>
-     function concat_event (op1, op2)
-       if (type(op1) == "string" or type(op1) == "number") and
-          (type(op2) == "string" or type(op2) == "number") then
-         return op1 .. op2  -- primitive string concatenation
-       else
-         local h = getbinhandler(op1, op2, "__concat")
-         if h then
-           return (h(op1, op2))
-         else
-           error(&middot;&middot;&middot;)
-         end
-       end
-     end
-</pre><p>
-</li>
-
-<li><b>"len":</b>
-the <code>#</code> operation.
-
-
-<pre>
-     function len_event (op)
-       if type(op) == "string" then
-         return strlen(op)         -- primitive string length
-       elseif type(op) == "table" then
-         return #op                -- primitive table length
-       else
-         local h = metatable(op).__len
-         if h then
-           -- call the handler with the operand
-           return (h(op))
-         else  -- no handler available: default behavior
-           error(&middot;&middot;&middot;)
-         end
-       end
-     end
-</pre><p>
-See <a href="#2.5.5">&sect;2.5.5</a> for a description of the length of a table.
-</li>
-
-<li><b>"eq":</b>
-the <code>==</code> operation.
-
-The function <code>getcomphandler</code> defines how Lua chooses a metamethod
-for comparison operators.
-A metamethod only is selected when both objects
-being compared have the same type
-and the same metamethod for the selected operation.
-
-<pre>
-     function getcomphandler (op1, op2, event)
-       if type(op1) ~= type(op2) then return nil end
-       local mm1 = metatable(op1)[event]
-       local mm2 = metatable(op2)[event]
-       if mm1 == mm2 then return mm1 else return nil end
-     end
-</pre><p>
-The "eq" event is defined as follows:
-
-<pre>
-     function eq_event (op1, op2)
-       if type(op1) ~= type(op2) then  -- different types?
-         return false   -- different objects
-       end
-       if op1 == op2 then   -- primitive equal?
-         return true   -- objects are equal
-       end
-       -- try metamethod
-       local h = getcomphandler(op1, op2, "__eq")
-       if h then
-         return (h(op1, op2))
-       else
-         return false
-       end
-     end
-</pre><p>
-<code>a ~= b</code> is equivalent to <code>not (a == b)</code>.
-</li>
-
-<li><b>"lt":</b>
-the <code>&lt;</code> operation.
-
-
-<pre>
-     function lt_event (op1, op2)
-       if type(op1) == "number" and type(op2) == "number" then
-         return op1 &lt; op2   -- numeric comparison
-       elseif type(op1) == "string" and type(op2) == "string" then
-         return op1 &lt; op2   -- lexicographic comparison
-       else
-         local h = getcomphandler(op1, op2, "__lt")
-         if h then
-           return (h(op1, op2))
-         else
-           error(&middot;&middot;&middot;)
-         end
-       end
-     end
-</pre><p>
-<code>a &gt; b</code> is equivalent to <code>b &lt; a</code>.
-</li>
-
-<li><b>"le":</b>
-the <code>&lt;=</code> operation.
-
-
-<pre>
-     function le_event (op1, op2)
-       if type(op1) == "number" and type(op2) == "number" then
-         return op1 &lt;= op2   -- numeric comparison
-       elseif type(op1) == "string" and type(op2) == "string" then
-         return op1 &lt;= op2   -- lexicographic comparison
-       else
-         local h = getcomphandler(op1, op2, "__le")
-         if h then
-           return (h(op1, op2))
-         else
-           h = getcomphandler(op1, op2, "__lt")
-           if h then
-             return not h(op2, op1)
-           else
-             error(&middot;&middot;&middot;)
-           end
-         end
-       end
-     end
-</pre><p>
-<code>a &gt;= b</code> is equivalent to <code>b &lt;= a</code>.
-Note that, in the absence of a "le" metamethod,
-Lua tries the "lt", assuming that <code>a &lt;= b</code> is
-equivalent to <code>not (b &lt; a)</code>.
-</li>
-
-<li><b>"index":</b>
-The indexing access <code>table[key]</code>.
-
-
-<pre>
-     function gettable_event (table, key)
-       local h
-       if type(table) == "table" then
-         local v = rawget(table, key)
-         if v ~= nil then return v end
-         h = metatable(table).__index
-         if h == nil then return nil end
-       else
-         h = metatable(table).__index
-         if h == nil then
-           error(&middot;&middot;&middot;)
-         end
-       end
-       if type(h) == "function" then
-         return (h(table, key))     -- call the handler
-       else return h[key]           -- or repeat operation on it
-       end
-     end
-</pre><p>
-</li>
-
-<li><b>"newindex":</b>
-The indexing assignment <code>table[key] = value</code>.
-
-
-<pre>
-     function settable_event (table, key, value)
-       local h
-       if type(table) == "table" then
-         local v = rawget(table, key)
-         if v ~= nil then rawset(table, key, value); return end
-         h = metatable(table).__newindex
-         if h == nil then rawset(table, key, value); return end
-       else
-         h = metatable(table).__newindex
-         if h == nil then
-           error(&middot;&middot;&middot;)
-         end
-       end
-       if type(h) == "function" then
-         h(table, key,value)           -- call the handler
-       else h[key] = value             -- or repeat operation on it
-       end
-     end
-</pre><p>
-</li>
-
-<li><b>"call":</b>
-called when Lua calls a value.
-
-
-<pre>
-     function function_event (func, ...)
-       if type(func) == "function" then
-         return func(...)   -- primitive call
-       else
-         local h = metatable(func).__call
-         if h then
-           return h(func, ...)
-         else
-           error(&middot;&middot;&middot;)
-         end
-       end
-     end
-</pre><p>
-</li>
-
-</ul>
-
-
-
-
-<h2>2.9 - <a name="2.9">Environments</a></h2>
-
-<p>
-Besides metatables,
-objects of types thread, function, and userdata
-have another table associated with them,
-called their <em>environment</em>.
-Like metatables, environments are regular tables and
-multiple objects can share the same environment.
-
-
-<p>
-Threads are created sharing the environment of the creating thread.
-Userdata and C&nbsp;functions are created sharing the environment
-of the creating C&nbsp;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&nbsp;code (see <a href="#3.3">&sect;3.3</a>).
-
-
-<p>
-The environment associated with a C&nbsp;function can be directly
-accessed by C&nbsp;code (see <a href="#3.3">&sect;3.3</a>).
-It is used as the default environment for other C&nbsp;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">&sect;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&nbsp;functions, other threads) you must
-use the C&nbsp;API.
-
-
-
-
-
-<h2>2.10 - <a name="2.10">Garbage Collection</a></h2>
-
-<p>
-Lua performs automatic memory management.
-This means that
-you have to worry neither about allocating memory for new objects
-nor about freeing it when the objects are no longer needed.
-Lua manages memory automatically by running
-a <em>garbage collector</em> from time to time
-to collect all <em>dead objects</em>
-(that is, 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&nbsp;API,
-you can set garbage-collector metamethods for userdata (see <a href="#2.8">&sect;2.8</a>).
-These metamethods are also called <em>finalizers</em>.
-Finalizers allow you to coordinate Lua's garbage collection
-with external resource management
-(such as closing files, network or database connections,
-or freeing your own memory).
-
-
-<p>
-Garbage userdata with a field <code>__gc</code> in their metatables are not
-collected immediately by the garbage collector.
-Instead, Lua puts them in a list.
-After the collection,
-Lua does the equivalent of the following function
-for each userdata in that list:
-
-<pre>
-     function gc_event (udata)
-       local h = metatable(udata).__gc
-       if h then
-         h(udata)
-       end
-     end
-</pre>
-
-<p>
-At the end of each garbage-collection cycle,
-the finalizers for userdata are called in <em>reverse</em>
-order of their creation,
-among those collected in that cycle.
-That is, the first finalizer to be called is the one associated
-with the userdata created last in the program.
-The userdata itself is freed only in the next garbage-collection cycle.
-
-
-
-
-
-<h3>2.10.2 - <a name="2.10.2">Weak Tables</a></h3>
-
-<p>
-A <em>weak table</em> is a table whose elements are
-<em>weak references</em>.
-A weak reference is ignored by the garbage collector.
-In other words,
-if the only references to an object are weak references,
-then the garbage collector will collect this object.
-
-
-<p>
-A weak table can have weak keys, weak values, or both.
-A table with weak keys allows the collection of its keys,
-but prevents the collection of its values.
-A table with both weak keys and weak values allows the collection of
-both keys and values.
-In any case, if either the key or the value is collected,
-the whole pair is removed from the table.
-The weakness of a table is controlled by the
-<code>__mode</code> field of its metatable.
-If the <code>__mode</code> field is a string containing the character&nbsp;'<code>k</code>',
-the keys in the table are weak.
-If <code>__mode</code> contains '<code>v</code>',
-the values in the table are weak.
-
-
-<p>
-After you use a table as a metatable,
-you should not change the value of its <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>
+<h1>4 &ndash; <a name="4">The Application Program Interface</a></h1>
 
 <p>
 
@@ -2259,7 +2439,7 @@ in file <code>luaconf.h</code>.
 
 
 
-<h2>3.1 - <a name="3.1">The Stack</a></h2>
+<h2>4.1 &ndash; <a name="4.1">The Stack</a></h2>
 
 <p>
 Lua uses a <em>virtual stack</em> to pass values to and from C.
@@ -2281,9 +2461,9 @@ 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
+A positive index represents an absolute stack position
 (starting at&nbsp;1);
-a negative index represents an <em>offset</em> relative to the top of the stack.
+a negative index represents an offset relative to the top of the stack.
 More specifically, if the stack has <em>n</em> elements,
 then index&nbsp;1 represents the first element
 (that is, the element that was pushed onto the stack first)
@@ -2301,15 +2481,15 @@ if it lies between&nbsp;1 and the stack top
 
 
 
-<h2>3.2 - <a name="3.2">Stack Size</a></h2>
+<h2>4.2 &ndash; <a name="4.2">Stack Size</a></h2>
 
 <p>
-When you interact with Lua API,
+When you interact with the 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.
+to ensure that the stack has extra slots when pushing new elements.
 
 
 <p>
@@ -2321,9 +2501,18 @@ unless your code has loops pushing elements onto the stack.
 
 
 <p>
+When you call a Lua function
+without a fixed number of results (see <a href="#lua_call"><code>lua_call</code></a>),
+Lua ensures that the stack has enough size for all results,
+but it does not ensure any extra space.
+So, before pushing anything in the stack after such a call
+you should use <a href="#lua_checkstack"><code>lua_checkstack</code></a>.
+
+
+<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>.
+that 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:
@@ -2338,40 +2527,22 @@ Note that 0 is never an acceptable index.
 
 
 
-<h2>3.3 - <a name="3.3">Pseudo-Indices</a></h2>
+<h2>4.3 &ndash; <a name="4.3">Pseudo-Indices</a></h2>
 
 <p>
 Unless otherwise noted,
-any function that accepts valid indices can also be called with
-<em>pseudo-indices</em>,
+any function that accepts valid indices also accepts <em>pseudo-indices</em>,
 which represent some Lua values that are accessible to C&nbsp;code
 but which are not in the stack.
-Pseudo-indices are used to access the thread environment,
-the function environment,
-the registry,
-and the upvalues of a C&nbsp;function (see <a href="#3.4">&sect;3.4</a>).
+Pseudo-indices are used to access
+the registry
+and the upvalues of a C&nbsp;function (see <a href="#4.4">&sect;4.4</a>).
 
 
-<p>
-The thread environment (where global variables live) is
-always at pseudo-index <a name="pdf-LUA_GLOBALSINDEX"><code>LUA_GLOBALSINDEX</code></a>.
-The environment of the running C&nbsp;function is always
-at pseudo-index <a name="pdf-LUA_ENVIRONINDEX"><code>LUA_ENVIRONINDEX</code></a>.
-
-
-<p>
-To access and change the value of global variables,
-you can use regular table operations over an environment table.
-For instance, to access the value of a global variable, do
-
-<pre>
-     lua_getfield(L, LUA_GLOBALSINDEX, varname);
-</pre>
 
 
 
-
-<h2>3.4 - <a name="3.4">C Closures</a></h2>
+<h2>4.4 &ndash; <a name="4.4">C Closures</a></h2>
 
 <p>
 When a C&nbsp;function is created,
@@ -2398,7 +2569,7 @@ produces an acceptable (but invalid) index.
 
 
 
-<h2>3.5 - <a name="3.5">Registry</a></h2>
+<h2>4.5 &ndash; <a name="4.5">Registry</a></h2>
 
 <p>
 Lua provides a <em>registry</em>,
@@ -2409,27 +2580,51 @@ This table is always located at pseudo-index
 Any C&nbsp;library can store data into this table,
 but it should take care to choose keys different from those used
 by other libraries, to avoid collisions.
-Typically, you should use as key a string containing your library name
-or a light userdata with the address of a C&nbsp;object in your code.
+Typically, you should use as key a string containing your library name,
+or a light userdata with the address of a C&nbsp;object in your code,
+or any Lua object created by your code.
+As with global names,
+string keys starting with an underscore followed by
+uppercase letters are reserved for Lua.
 
 
 <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.
+and by some predefined values.
+Therefore, integer keys should not be used for other purposes.
+
+
+<p>
+When you create a new Lua state,
+its registry comes with some predefined values.
+These predefined values are indexed with integer keys
+defined as constants in <code>lua.h</code>.
+The following constants are defined:
+
+<ul>
+<li><b><a name="pdf-LUA_RIDX_MAINTHREAD"><code>LUA_RIDX_MAINTHREAD</code></a>: </b> At this index the registry has
+the main thread of the state.
+(The main thread is the one created together with the state.)
+</li>
 
+<li><b><a name="pdf-LUA_RIDX_GLOBALS"><code>LUA_RIDX_GLOBALS</code></a>: </b> At this index the registry has
+the global environment.
+This is the C&nbsp;equivalent to the <a href="#pdf-_G"><code>_G</code></a> global variable.
+</li>
+</ul>
 
 
 
 
-<h2>3.6 - <a name="3.6">Error Handling in C</a></h2>
+<h2>4.6 &ndash; <a name="4.6">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,
+(such as a memory allocation error, type errors, syntax errors,
 and runtime errors)
 it <em>raises</em> an error;
 that is, it does a long jump.
@@ -2439,6 +2634,15 @@ any error jumps to the most recent active recover point.
 
 
 <p>
+If an error happens outside any protected environment,
+Lua calls a <em>panic function</em> (see <a href="#lua_atpanic"><code>lua_atpanic</code></a>)
+and then calls <code>abort</code>,
+thus exiting the host application.
+Your panic function can avoid this exit by
+never returning (e.g., doing a long jump).
+
+
+<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
@@ -2452,7 +2656,75 @@ Inside a C&nbsp;function you can throw an error by calling <a href="#lua_error">
 
 
 
-<h2>3.7 - <a name="3.7">Functions and Types</a></h2>
+<h2>4.7 &ndash; <a name="4.7">Handling Yields in C</a></h2>
+
+<p>
+Internally, Lua uses the C <code>longjmp</code> facility to yield a coroutine.
+Therefore, if a function <code>foo</code> calls an API function
+and this API function yields
+(directly or indirectly by calling another function that yields),
+Lua cannot return to <code>foo</code> any more,
+because the <code>longjmp</code> removes its frame from the C stack.
+
+
+<p>
+To avoid this kind of problem,
+Lua raises an error whenever it tries to yield across an API call,
+except for three functions:
+<a href="#lua_yieldk"><code>lua_yieldk</code></a>, <a href="#lua_callk"><code>lua_callk</code></a>, and <a href="#lua_pcallk"><code>lua_pcallk</code></a>.
+All those functions receive a <em>continuation function</em>
+(as a parameter called <code>k</code>) to continue execution after an yield.
+
+
+<p>
+To explain continuations,
+let us set some terminology.
+We have a C function called from Lua which we will call
+the <em>original function</em>.
+This original function then calls one of those three functions in the C API,
+which we will call the <em>callee function</em>,
+that then yields the current thread.
+(This can happen when the callee function is <a href="#lua_yieldk"><code>lua_yieldk</code></a>,
+or when the callee function is either <a href="#lua_callk"><code>lua_callk</code></a> or <a href="#lua_pcallk"><code>lua_pcallk</code></a>
+and the function called by them yields.)
+
+
+<p>
+Suppose the running thread yields while executing the callee function.
+After the thread resumes,
+it eventually will finish running the callee function.
+However,
+the callee function cannot return to the original function,
+because its frame in the C stack was destroyed by the yield.
+Instead, Lua calls a <em>continuation function</em>,
+which was given as an argument to the callee function.
+As the name implies,
+the continuation function should continue the task
+of the original function.
+
+
+<p>
+Lua treats the continuation function as if it was the original function.
+The continuation function receives the same Lua stack
+from the original function,
+in the same state it would be if the callee function had returned.
+(For instance,
+after a <a href="#lua_callk"><code>lua_callk</code></a> the function and its arguments are
+removed from the stack and replaced by the results from the call.)
+It also has the same upvalues.
+Whatever it returns is handled by Lua as if it was the return
+of the original function.
+
+
+<p>
+The only difference in the Lua state between the original function
+and its continuation is the result of a call to <a href="#lua_getctx"><code>lua_getctx</code></a>.
+
+
+
+
+
+<h2>4.8 &ndash; <a name="4.8">Functions and Types</a></h2>
 
 <p>
 Here we list all functions and types from the C&nbsp;API in
@@ -2484,6 +2756,18 @@ only due to not enough memory;
 
 
 
+<hr><h3><a name="lua_absindex"><code>lua_absindex</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_absindex (lua_State *L, int idx);</pre>
+
+<p>
+Converts the acceptable index <code>idx</code> into an absolute index
+(that is, one that does not depend on the stack top).
+
+
+
+
+
 <hr><h3><a name="lua_Alloc"><code>lua_Alloc</code></a></h3>
 <pre>typedef void * (*lua_Alloc) (void *ud,
                              void *ptr,
@@ -2498,18 +2782,43 @@ 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>osize</code>, the original size of the block or some code about what
+is being allocated;
 <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>
+
+
+<p>
+When <code>ptr</code> is not <code>NULL</code>,
+<code>osize</code> is the size of the block pointed by <code>ptr</code>,
+that is, the size given when it was allocated or reallocated.
+
+
+<p>
+When <code>ptr</code> is <code>NULL</code>,
+<code>osize</code> codes the kind of object that Lua is allocating.
+<code>osize</code> is any of
+<a href="#pdf-LUA_TSTRING"><code>LUA_TSTRING</code></a>, <a href="#pdf-LUA_TTABLE"><code>LUA_TTABLE</code></a>, <a href="#pdf-LUA_TFUNCTION"><code>LUA_TFUNCTION</code></a>,
+<a href="#pdf-LUA_TUSERDATA"><code>LUA_TUSERDATA</code></a>, or <a href="#pdf-LUA_TTHREAD"><code>LUA_TTHREAD</code></a> when (and only when)
+Lua is creating a new object of that type.
+When <code>osize</code> is some other value,
+Lua is allocating memory for something else.
+
+
+<p>
+Lua assumes the following behavior from the allocator function:
+
+
+<p>
+When <code>nsize</code> is zero,
+the allocator should behave like <code>free</code>
+and return <code>NULL</code>.
+
+
+<p>
+When <code>nsize</code> is not zero,
+the allocator should behave like <code>realloc</code>.
+The allocator returns <code>NULL</code>
 if and only if it cannot fill the request.
-When <code>nsize</code> is not zero and <code>osize</code> is zero,
-the allocator should behave like <code>malloc</code>.
-When <code>nsize</code> and <code>osize</code> are not zero,
-the allocator behaves like <code>realloc</code>.
 Lua assumes that the allocator never fails when
 <code>osize &gt;= nsize</code>.
 
@@ -2530,34 +2839,62 @@ It is used in the auxiliary library by <a href="#luaL_newstate"><code>luaL_newst
          return realloc(ptr, nsize);
      }
 </pre><p>
-This code assumes
+Note that Standard&nbsp;C ensures
 that <code>free(NULL)</code> has no effect and that
 <code>realloc(NULL, size)</code> is equivalent to <code>malloc(size)</code>.
-ANSI&nbsp;C ensures both behaviors.
+This code assumes that <code>realloc</code> does not fail when shrinking a block.
+Standard&nbsp;C does not ensure this behavior,
+but it seems a safe assumption.
 
 
 
 
 
-<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>
+<hr><h3><a name="lua_arith"><code>lua_arith</code></a></h3><p>
+<span class="apii">[-(2|1), +1, <em>e</em>]</span>
+<pre>int lua_arith (lua_State *L, int op);</pre>
 
 <p>
-Sets a new panic function and returns the old one.
+Performs an arithmetic operation over the two values
+(or one, in the case of negation)
+at the top of the stack,
+with the value at the top being the second operand,
+pops these values, and pushes the result of the operation.
+The function follows the semantics of the corresponding Lua operator
+(that is, it may call metamethods).
 
 
 <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).
+The value of <code>op</code> must be one of the following constants:
 
+<ul>
+
+<li><b><a name="pdf-LUA_OPADD"><code>LUA_OPADD</code></a>: </b> performs addition (<code>+</code>)</li>
+<li><b><a name="pdf-LUA_OPSUB"><code>LUA_OPSUB</code></a>: </b> performs subtraction (<code>-</code>)</li>
+<li><b><a name="pdf-LUA_OPMUL"><code>LUA_OPMUL</code></a>: </b> performs multiplication (<code>*</code>)</li>
+<li><b><a name="pdf-LUA_OPDIV"><code>LUA_OPDIV</code></a>: </b> performs division (<code>/</code>)</li>
+<li><b><a name="pdf-LUA_OPMOD"><code>LUA_OPMOD</code></a>: </b> performs modulo (<code>%</code>)</li>
+<li><b><a name="pdf-LUA_OPPOW"><code>LUA_OPPOW</code></a>: </b> performs exponentiation (<code>^</code>)</li>
+<li><b><a name="pdf-LUA_OPUNM"><code>LUA_OPUNM</code></a>: </b> performs mathematical negation (unary <code>-</code>)</li>
+
+</ul>
+
+
+
+
+<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>
-The panic function can access the error message at the top of the stack.
+Sets a new panic function and returns the old one (see <a href="#4.6">&sect;4.6</a>).
+
+
+<p>
+The panic function should not try to run anything on the failed Lua state.
+However, it can still use the debug API (see <a href="#4.9">&sect;4.9</a>)
+to gather information about the state.
+In particular, the error message is at the top of the stack.
 
 
 
@@ -2584,7 +2921,7 @@ 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.
+In this case, all 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),
@@ -2606,14 +2943,14 @@ equivalent to this Lua code:
 Here it is in&nbsp;C:
 
 <pre>
-     lua_getfield(L, LUA_GLOBALSINDEX, "f"); /* function to be called */
+     lua_getglobal(L, "f");                  /* function to be called */
      lua_pushstring(L, "how");                        /* 1st argument */
-     lua_getfield(L, LUA_GLOBALSINDEX, "t");   /* table to be indexed */
+     lua_getglobal(L, "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' */
+     lua_setglobal(L, "a");                         /* set global 'a' */
 </pre><p>
 Note that the code above is "balanced":
 at its end, the stack is back to its original configuration.
@@ -2623,6 +2960,19 @@ This is considered good programming practice.
 
 
 
+<hr><h3><a name="lua_callk"><code>lua_callk</code></a></h3><p>
+<span class="apii">[-(nargs + 1), +nresults, <em>e</em>]</span>
+<pre>void lua_callk (lua_State *L, int nargs, int nresults, int ctx,
+                lua_CFunction k);</pre>
+
+<p>
+This function behaves exactly like <a href="#lua_call"><code>lua_call</code></a>,
+but allows the called function to yield (see <a href="#4.7">&sect;4.7</a>).
+
+
+
+
+
 <hr><h3><a name="lua_CFunction"><code>lua_CFunction</code></a></h3>
 <pre>typedef int (*lua_CFunction) (lua_State *L);</pre>
 
@@ -2675,12 +3025,15 @@ of numerical arguments and returns their average and sum:
 
 
 <hr><h3><a name="lua_checkstack"><code>lua_checkstack</code></a></h3><p>
-<span class="apii">[-0, +0, <em>m</em>]</span>
+<span class="apii">[-0, +0, <em>-</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.
+It returns false if it cannot grant the request,
+because it would cause the stack to be larger than a fixed maximum size
+(typically at least a few thousand elements) or
+because it cannot allocate memory for the new stack size.
 This function never shrinks the stack;
 if the stack is already larger than the new size,
 it is left unchanged.
@@ -2708,6 +3061,33 @@ to avoid growing too large.
 
 
 
+<hr><h3><a name="lua_compare"><code>lua_compare</code></a></h3><p>
+<span class="apii">[-0, +0, <em>e</em>]</span>
+<pre>int lua_compare (lua_State *L, int index1, int index2, int op);</pre>
+
+<p>
+Returns 1 if the value at acceptable index <code>index1</code> satisfies <code>op</code>
+when compared with the value at acceptable index <code>index2</code>,
+following the semantics of the corresponding Lua operator
+(that is, it may call metamethods).
+Otherwise returns&nbsp;0.
+Also returns&nbsp;0 if any of the indices is non valid.
+
+
+<p>
+The value of <code>op</code> must be one of the following constants:
+
+<ul>
+
+<li><b><a name="pdf-LUA_OPEQ"><code>LUA_OPEQ</code></a>: </b> compares for equality (<code>==</code>)</li>
+<li><b><a name="pdf-LUA_OPLT"><code>LUA_OPLT</code></a>: </b> compares for less than (<code>&lt;</code>)</li>
+<li><b><a name="pdf-LUA_OPLE"><code>LUA_OPLE</code></a>: </b> compares for less or equal (<code>&lt;=</code>)</li>
+
+</ul>
+
+
+
+
 <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>
@@ -2719,25 +3099,21 @@ If <code>n</code>&nbsp;is&nbsp;1, the result is the single value on the stack
 (that is, the function does nothing);
 if <code>n</code> is 0, the result is the empty string.
 Concatenation is performed following the usual semantics of Lua
-(see <a href="#2.5.4">&sect;2.5.4</a>).
+(see <a href="#3.4.5">&sect;3.4.5</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>
+<hr><h3><a name="lua_copy"><code>lua_copy</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>void lua_copy (lua_State *L, int fromidx, int toidx);</pre>
 
 <p>
-Calls the C&nbsp;function <code>func</code> in protected mode.
-<code>func</code> starts with only one element in its stack,
-a light userdata containing <code>ud</code>.
-In case of errors,
-<a href="#lua_cpcall"><code>lua_cpcall</code></a> returns the same error codes as <a href="#lua_pcall"><code>lua_pcall</code></a>,
-plus the error object on the top of the stack;
-otherwise, it returns zero, and does not change the stack.
-All values returned by <code>func</code> are discarded.
+Moves the element at the valid index <code>fromidx</code>
+into the valid index <code>toidx</code>
+without shifting any element
+(therefore replacing the value at that position).
 
 
 
@@ -2749,10 +3125,13 @@ All values returned by <code>func</code> are discarded.
 
 <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
+Parameter <code>narr</code> is a hint for how many elements the table
+will have as a sequence;
+parameter <code>nrec</code> is a hint for how many other elements
 the table will have.
+Lua may use these hints to preallocate memory for the new table.
+This pre-allocation is useful for performance when you know in advance
+how many elements the table will have.
 Otherwise you can use the function <a href="#lua_newtable"><code>lua_newtable</code></a>.
 
 
@@ -2788,22 +3167,6 @@ This function does not pop the Lua function from the stack.
 
 
 
-<hr><h3><a name="lua_equal"><code>lua_equal</code></a></h3><p>
-<span class="apii">[-0, +0, <em>e</em>]</span>
-<pre>int lua_equal (lua_State *L, int index1, int index2);</pre>
-
-<p>
-Returns 1 if the two values in acceptable indices <code>index1</code> and
-<code>index2</code> are equal,
-following the semantics of the Lua <code>==</code> operator
-(that is, may call metamethods).
-Otherwise returns&nbsp;0.
-Also returns&nbsp;0 if any of the indices is non valid.
-
-
-
-
-
 <hr><h3><a name="lua_error"><code>lua_error</code></a></h3><p>
 <span class="apii">[-1, +0, <em>v</em>]</span>
 <pre>int lua_error (lua_State *L);</pre>
@@ -2834,28 +3197,28 @@ according to the value of the parameter <code>what</code>:
 
 <ul>
 
-<li><b><code>LUA_GCSTOP</code>:</b>
+<li><b><code>LUA_GCSTOP</code>: </b>
 stops the garbage collector.
 </li>
 
-<li><b><code>LUA_GCRESTART</code>:</b>
+<li><b><code>LUA_GCRESTART</code>: </b>
 restarts the garbage collector.
 </li>
 
-<li><b><code>LUA_GCCOLLECT</code>:</b>
+<li><b><code>LUA_GCCOLLECT</code>: </b>
 performs a full garbage-collection cycle.
 </li>
 
-<li><b><code>LUA_GCCOUNT</code>:</b>
+<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>
+<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>
+<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.
@@ -2865,20 +3228,30 @@ The function returns 1 if the step finished a
 garbage-collection cycle.
 </li>
 
-<li><b><code>LUA_GCSETPAUSE</code>:</b>
+<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">&sect;2.10</a>).
+for the <em>pause</em> of the collector (see <a href="#2.5">&sect;2.5</a>).
 The function returns the previous value of the pause.
 </li>
 
-<li><b><code>LUA_GCSETSTEPMUL</code>:</b>
+<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">&sect;2.10</a>).
+the collector (see <a href="#2.5">&sect;2.5</a>).
 The function returns the previous value of the step multiplier.
 </li>
 
+<li><b><code>LUA_GCISRUNNING</code>: </b>
+returns a boolean that tells whether the collector is running
+(i.e., not stopped).
+</li>
+
 </ul>
 
+<p>
+For more details about some options,
+see <a href="#pdf-collectgarbage"><code>collectgarbage</code></a>.
+
+
 
 
 
@@ -2895,13 +3268,37 @@ 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>
+<hr><h3><a name="lua_getctx"><code>lua_getctx</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>int lua_getctx  (lua_State *L, int *ctx);</pre>
+
+<p>
+This function is called by a continuation function (see <a href="#4.7">&sect;4.7</a>)
+to retrieve the status of the thread and a context information.
+
+
+<p>
+When called in the original function,
+<a href="#lua_getctx"><code>lua_getctx</code></a> always returns <a href="#pdf-LUA_OK"><code>LUA_OK</code></a>
+and does not change the value of its argument <code>ctx</code>.
+When called inside a continuation function,
+<a href="#lua_getctx"><code>lua_getctx</code></a> returns <a href="#pdf-LUA_YIELD"><code>LUA_YIELD</code></a> and sets
+the value of <code>ctx</code> to be the context information
+(the value passed as the <code>ctx</code> argument
+to the callee together with the continuation function).
+
 
 <p>
-Pushes onto the stack the environment table of
-the value at the given index.
+When the callee is <a href="#lua_pcallk"><code>lua_pcallk</code></a>,
+Lua may also call its continuation function
+to handle errors during the call.
+That is, upon an error in the function called by <a href="#lua_pcallk"><code>lua_pcallk</code></a>,
+Lua may not return <a href="#lua_pcallk"><code>lua_pcallk</code></a>
+but instead may call the continuation function.
+In that case, a call to <a href="#lua_getctx"><code>lua_getctx</code></a> will return the error code
+(the value that would be returned by <a href="#lua_pcallk"><code>lua_pcallk</code></a>);
+the value of <code>ctx</code> will be set to the context information,
+as in the case of an yield.
 
 
 
@@ -2915,7 +3312,7 @@ the value at the given index.
 Pushes onto the stack the value <code>t[k]</code>,
 where <code>t</code> is the value at the given valid index.
 As in Lua, this function may trigger a metamethod
-for the "index" event (see <a href="#2.8">&sect;2.8</a>).
+for the "index" event (see <a href="#2.4">&sect;2.4</a>).
 
 
 
@@ -2927,11 +3324,8 @@ for the "index" event (see <a href="#2.8">&sect;2.8</a>).
 
 <p>
 Pushes onto the stack the value of the global <code>name</code>.
-It is defined as a macro:
+It is defined as a macro.
 
-<pre>
-     #define lua_getglobal(L,s)  lua_getfield(L, LUA_GLOBALSINDEX, s)
-</pre>
 
 
 
@@ -2965,7 +3359,7 @@ and <code>k</code> is the value at the top of the stack.
 This function pops the key from the stack
 (putting the resulting value in its place).
 As in Lua, this function may trigger a metamethod
-for the "index" event (see <a href="#2.8">&sect;2.8</a>).
+for the "index" event (see <a href="#2.4">&sect;2.4</a>).
 
 
 
@@ -2985,6 +3379,19 @@ this result is equal to the number of elements in the stack
 
 
 
+<hr><h3><a name="lua_getuservalue"><code>lua_getuservalue</code></a></h3><p>
+<span class="apii">[-0, +1, <em>-</em>]</span>
+<pre>void lua_getuservalue (lua_State *L, int index);</pre>
+
+<p>
+Pushes onto the stack the Lua value associated with the userdata
+at the given index.
+This Lua value must be a table or <b>nil</b>.
+
+
+
+
+
 <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>
@@ -3003,7 +3410,7 @@ because a pseudo-index is not an actual stack position.
 <pre>typedef ptrdiff_t lua_Integer;</pre>
 
 <p>
-The type used by the Lua API to represent integral values.
+The type used by the Lua API to represent signed integral values.
 
 
 <p>
@@ -3164,17 +3571,14 @@ Returns 1 if the value at the given acceptable index is a userdata
 
 
 
-<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>
+<hr><h3><a name="lua_len"><code>lua_len</code></a></h3><p>
+<span class="apii">[-0, +1, <em>e</em>]</span>
+<pre>void lua_len (lua_State *L, int index);</pre>
 
 <p>
-Returns 1 if the value at acceptable index <code>index1</code> is smaller
-than the value at acceptable index <code>index2</code>,
-following the semantics of the Lua <code>&lt;</code> operator
-(that is, may call metamethods).
-Otherwise returns&nbsp;0.
-Also returns&nbsp;0 if any of the indices is non valid.
+Returns the "length" of the value at the given acceptable index;
+it is equivalent to the '<code>#</code>' operator in Lua (see <a href="#3.4.6">&sect;3.4.6</a>).
+The result is pushed on the stack.
 
 
 
@@ -3185,7 +3589,7 @@ Also returns&nbsp;0 if any of the indices is non valid.
 <pre>int lua_load (lua_State *L,
               lua_Reader reader,
               void *data,
-              const char *chunkname);</pre>
+              const char *source);</pre>
 
 <p>
 Loads a Lua chunk.
@@ -3197,14 +3601,20 @@ 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 href="#pdf-LUA_OK"><code>LUA_OK</code></a> (0): </b> no errors;</li>
 
-<li><b><a name="pdf-LUA_ERRSYNTAX"><code>LUA_ERRSYNTAX</code></a>:</b>
+<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>
+<li><b><a href="#pdf-LUA_ERRMEM"><code>LUA_ERRMEM</code></a>: </b>
 memory allocation error.</li>
 
+<li><b><a href="#pdf-LUA_ERRGCMM"><code>LUA_ERRGCMM</code></a>: </b>
+error while running a <code>__gc</code> metamethod.
+(This error has no relation with the chunk being loaded.
+It is generated by the garbage collector.)
+</li>
+
 </ul>
 
 <p>
@@ -3224,8 +3634,16 @@ The <code>data</code> argument is an opaque value passed to the reader function.
 
 
 <p>
-The <code>chunkname</code> argument gives a name to the chunk,
-which is used for error messages and in debug information (see <a href="#3.8">&sect;3.8</a>).
+The <code>source</code> argument gives a name to the chunk,
+which is used for error messages and in debug information (see <a href="#4.9">&sect;4.9</a>).
+
+
+<p>
+If the resulting function has one upvalue,
+this upvalue is set to the value of the global environment
+stored at index <code>LUA_RIDX_GLOBALS</code> in the registry (see <a href="#4.5">&sect;4.5</a>).
+(When loading main chunks,
+this upvalue will be the <code>_ENV</code> variable (see <a href="#2.2">&sect;2.2</a>).)
 
 
 
@@ -3236,8 +3654,8 @@ which is used for error messages and in debug information (see <a href="#3.8">&s
 <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
+Creates a new thread running in a new, independent state.
+Returns <code>NULL</code> if cannot create the thread/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.
@@ -3267,7 +3685,7 @@ It is equivalent to <code>lua_createtable(L, 0, 0)</code>.
 <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
+The new thread returned by this function shares with the original thread
 all global objects (such as tables),
 but has an independent execution stack.
 
@@ -3300,13 +3718,6 @@ 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.
-
-
 
 
 
@@ -3316,7 +3727,7 @@ Lua frees its corresponding memory.
 
 <p>
 Pops a key from the stack,
-and pushes a key-value pair from the table at the given index
+and pushes a key&ndash;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).
@@ -3342,11 +3753,16 @@ A typical traversal looks like this:
 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>
+Recall that <a href="#lua_tolstring"><code>lua_tolstring</code></a> may change
 the value at the given index;
 this confuses the next call to <a href="#lua_next"><code>lua_next</code></a>.
 
 
+<p>
+See function <a href="#pdf-next"><code>next</code></a> for the caveats of modifying
+the table during its traversal.
+
+
 
 
 
@@ -3356,35 +3772,16 @@ this confuses the next call to <a href="#lua_next"><code>lua_next</code></a>.
 <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
+Through this configuration file you can change
 Lua to operate with another type for numbers (e.g., float or long).
 
 
 
 
 
-<hr><h3><a name="lua_objlen"><code>lua_objlen</code></a></h3><p>
-<span class="apii">[-0, +0, <em>-</em>]</span>
-<pre>size_t lua_objlen (lua_State *L, int index);</pre>
-
-<p>
-Returns the "length" of the value at the given acceptable index:
-for strings, this is the string length;
-for tables, this is the result of the length operator ('<code>#</code>');
-for userdata, this is the size of the block of memory allocated
-for the userdata;
-for other values, it is&nbsp;0.
-
-
-
-
-
 <hr><h3><a name="lua_pcall"><code>lua_pcall</code></a></h3><p>
 <span class="apii">[-(nargs + 1), +(nresults|1), <em>-</em>]</span>
-<pre>int lua_pcall (lua_State *L, int nargs, int nresults, int errfunc);</pre>
+<pre>int lua_pcall (lua_State *L, int nargs, int nresults, int msgh);</pre>
 
 <p>
 Calls a function in protected mode.
@@ -3405,42 +3802,51 @@ and its arguments from the stack.
 
 
 <p>
-If <code>errfunc</code> is 0,
+If <code>msgh</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>.
+Otherwise, <code>msgh</code> is the stack index of a
+<em>message handler</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>.
+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
+Typically, the message handler 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
+The <a href="#lua_pcall"><code>lua_pcall</code></a> function returns one of the following codes
 (defined in <code>lua.h</code>):
 
 <ul>
 
-<li><b><a name="pdf-LUA_ERRRUN"><code>LUA_ERRRUN</code></a>:</b>
+<li><b><a name="pdf-LUA_OK"><code>LUA_OK</code></a> (0): </b>
+success.</li>
+
+<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>
+<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.
+For such errors, Lua does not call the message handler.
 </li>
 
-<li><b><a name="pdf-LUA_ERRERR"><code>LUA_ERRERR</code></a>:</b>
-error while running the error handler function.
+<li><b><a name="pdf-LUA_ERRERR"><code>LUA_ERRERR</code></a>: </b>
+error while running the message handler.
+</li>
+
+<li><b><a name="pdf-LUA_ERRGCMM"><code>LUA_ERRGCMM</code></a>: </b>
+error while running a <code>__gc</code> metamethod.
+(This error typically has no relation with the function being called.
+It is generated by the garbage collector.)
 </li>
 
 </ul>
@@ -3448,6 +3854,19 @@ error while running the error handler function.
 
 
 
+<hr><h3><a name="lua_pcallk"><code>lua_pcallk</code></a></h3><p>
+<span class="apii">[-(nargs + 1), +(nresults|1), <em>-</em>]</span>
+<pre>int lua_pcallk (lua_State *L, int nargs, int nresults, int errfunc,
+                int ctx, lua_CFunction k);</pre>
+
+<p>
+This function behaves exactly like <a href="#lua_pcall"><code>lua_pcall</code></a>,
+but allows the called function to yield (see <a href="#4.7">&sect;4.7</a>).
+
+
+
+
+
 <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>
@@ -3481,7 +3900,7 @@ Pushes a new C&nbsp;closure onto the stack.
 <p>
 When a C&nbsp;function is created,
 it is possible to associate some values with it,
-thus creating a C&nbsp;closure (see <a href="#3.4">&sect;3.4</a>);
+thus creating a C&nbsp;closure (see <a href="#4.4">&sect;4.4</a>);
 these values are then accessible to the function whenever it is called.
 To associate values with a C&nbsp;function,
 first these values should be pushed onto the stack
@@ -3497,11 +3916,18 @@ associated with the function.
 The maximum value for <code>n</code> is 255.
 
 
+<p>
+When <code>n</code> is zero,
+this function creates a <em>light C function</em>,
+which is just a pointer to the C&nbsp;function.
+In that case, it cannot throw a memory error.
+
+
 
 
 
 <hr><h3><a name="lua_pushcfunction"><code>lua_pushcfunction</code></a></h3><p>
-<span class="apii">[-0, +1, <em>m</em>]</span>
+<span class="apii">[-0, +1, <em>-</em>]</span>
 <pre>void lua_pushcfunction (lua_State *L, lua_CFunction f);</pre>
 
 <p>
@@ -3583,7 +4009,7 @@ Pushes a light userdata onto the stack.
 
 <p>
 Userdata represent C&nbsp;values in Lua.
-A <em>light userdata</em> represents a pointer.
+A <em>light userdata</em> represents a pointer, a <code>void*</code>.
 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).
@@ -3596,7 +4022,7 @@ light userdata with the same C&nbsp;address.
 
 <hr><h3><a name="lua_pushliteral"><code>lua_pushliteral</code></a></h3><p>
 <span class="apii">[-0, +1, <em>m</em>]</span>
-<pre>void lua_pushliteral (lua_State *L, const char *s);</pre>
+<pre>const char *lua_pushliteral (lua_State *L, const char *s);</pre>
 
 <p>
 This macro is equivalent to <a href="#lua_pushlstring"><code>lua_pushlstring</code></a>,
@@ -3609,7 +4035,7 @@ 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>
+<pre>const char *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>
@@ -3617,7 +4043,12 @@ 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.
+The string can contain any binary data,
+including embedded zeros.
+
+
+<p>
+Returns a pointer to the internal copy of the string.
 
 
 
@@ -3647,7 +4078,7 @@ 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>
+<pre>const char *lua_pushstring (lua_State *L, const char *s);</pre>
 
 <p>
 Pushes the zero-terminated string pointed to by <code>s</code>
@@ -3655,8 +4086,14 @@ 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.
+
+
+<p>
+Returns a pointer to the internal copy of the string.
+
+
+<p>
+If <code>s</code> is <code>NULL</code>, pushes <b>nil</b> and returns <code>NULL</code>.
 
 
 
@@ -3733,7 +4170,7 @@ Similar to <a href="#lua_gettable"><code>lua_gettable</code></a>, but does a raw
 
 <p>
 Pushes onto the stack the value <code>t[n]</code>,
-where <code>t</code> is the value at the given valid index.
+where <code>t</code> is the table at the given valid index.
 The access is raw;
 that is, it does not invoke metamethods.
 
@@ -3741,6 +4178,23 @@ that is, it does not invoke metamethods.
 
 
 
+<hr><h3><a name="lua_rawlen"><code>lua_rawlen</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>size_t lua_rawlen (lua_State *L, int index);</pre>
+
+<p>
+Returns the raw "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>')
+with no metamethods;
+for userdata, this is the size of the block of memory allocated
+for the userdata;
+for other values, it is&nbsp;0.
+
+
+
+
+
 <hr><h3><a name="lua_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>
@@ -3759,7 +4213,7 @@ Similar to <a href="#lua_settable"><code>lua_settable</code></a>, but does a raw
 
 <p>
 Does the equivalent of <code>t[n] = v</code>,
-where <code>t</code> is the value at the given valid index
+where <code>t</code> is the table at the given valid index
 and <code>v</code> is the value at the top of the stack.
 
 
@@ -3831,9 +4285,10 @@ because a pseudo-index is not an actual stack position.
 <pre>void lua_replace (lua_State *L, int index);</pre>
 
 <p>
-Moves the top element into the given position (and pops it),
+Moves the top element into the given position
 without shifting any element
-(therefore replacing the value at the given position).
+(therefore replacing the value at the given position),
+and then pops the top element.
 
 
 
@@ -3848,9 +4303,8 @@ 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;
+To start a coroutine,
+you push onto the thread 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.
@@ -3858,14 +4312,20 @@ When it returns, the stack contains all values passed to <a href="#lua_yield"><c
 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
+<a href="#pdf-LUA_OK"><code>LUA_OK</code></a> 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>).
+
+
+<p>
 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
+
+
+<p>
+To resume 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>.
 
@@ -3885,22 +4345,6 @@ 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>
@@ -3914,7 +4358,7 @@ and <code>v</code> is the value at the top of the stack.
 <p>
 This function pops the value from the stack.
 As in Lua, this function may trigger a metamethod
-for the "newindex" event (see <a href="#2.8">&sect;2.8</a>).
+for the "newindex" event (see <a href="#2.4">&sect;2.4</a>).
 
 
 
@@ -3927,18 +4371,15 @@ for the "newindex" event (see <a href="#2.8">&sect;2.8</a>).
 <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:
+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>
+<pre>void lua_setmetatable (lua_State *L, int index);</pre>
 
 <p>
 Pops a table from the stack and
@@ -3963,7 +4404,7 @@ and <code>k</code> is the value just below the top.
 <p>
 This function pops both the key and the value from the stack.
 As in Lua, this function may trigger a metamethod
-for the "newindex" event (see <a href="#2.8">&sect;2.8</a>).
+for the "newindex" event (see <a href="#2.4">&sect;2.4</a>).
 
 
 
@@ -3984,11 +4425,23 @@ If <code>index</code> is&nbsp;0, then all stack elements are removed.
 
 
 
+<hr><h3><a name="lua_setuservalue"><code>lua_setuservalue</code></a></h3><p>
+<span class="apii">[-1, +0, <em>-</em>]</span>
+<pre>void lua_setuservalue (lua_State *L, int index);</pre>
+
+<p>
+Pops a table or <b>nil</b> from the stack and sets it as
+the new value associated to the userdata at the given index.
+
+
+
+
+
 <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.
+An 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.
@@ -4012,11 +4465,19 @@ 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,
+The status can be 0 (<a href="#pdf-LUA_OK"><code>LUA_OK</code></a>) for a normal thread,
+an error code if the thread finished the execution
+of a <a href="#lua_resume"><code>lua_resume</code></a> with an error,
 or <a name="pdf-LUA_YIELD"><code>LUA_YIELD</code></a> if the thread is suspended.
 
 
+<p>
+You can only call functions in threads with status <a href="#pdf-LUA_OK"><code>LUA_OK</code></a>.
+You can resume threads with status <a href="#pdf-LUA_OK"><code>LUA_OK</code></a>
+(to start a new coroutine) or <a href="#pdf-LUA_YIELD"><code>LUA_YIELD</code></a>
+(to resume a coroutine).
+
+
 
 
 
@@ -4028,10 +4489,10 @@ or <a name="pdf-LUA_YIELD"><code>LUA_YIELD</code></a> if the thread is suspended
 Converts the Lua value at the given acceptable index to a C&nbsp;boolean
 value (0&nbsp;or&nbsp;1).
 Like all tests in Lua,
-<a href="#lua_toboolean"><code>lua_toboolean</code></a> returns 1 for any Lua value
+<a href="#lua_toboolean"><code>lua_toboolean</code></a> returns true 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.
+otherwise it returns false.
+It also returns false 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.)
 
@@ -4057,11 +4518,22 @@ otherwise, returns <code>NULL</code>.
 <pre>lua_Integer lua_tointeger (lua_State *L, int index);</pre>
 
 <p>
+A macro equivalent to <code>lua_tointegerx(L, index, NULL)</code>.
+
+
+
+
+
+<hr><h3><a name="lua_tointegerx"><code>lua_tointegerx</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>lua_Integer lua_tointegerx (lua_State *L, int index, int *isnum);</pre>
+
+<p>
 Converts the Lua value at the given acceptable index
 to the signed integral type <a href="#lua_Integer"><code>lua_Integer</code></a>.
 The Lua value must be a number or a string convertible to a number
-(see <a href="#2.2.1">&sect;2.2.1</a>);
-otherwise, <a href="#lua_tointeger"><code>lua_tointeger</code></a> returns&nbsp;0.
+(see <a href="#3.4.2">&sect;3.4.2</a>);
+otherwise, <a href="#lua_tointegerx"><code>lua_tointegerx</code></a> returns&nbsp;0.
 
 
 <p>
@@ -4069,6 +4541,12 @@ If the number is not an integer,
 it is truncated in some non-specified way.
 
 
+<p>
+If <code>isnum</code> is different from <code>NULL</code>,
+its referent is assigned a boolean value that
+indicates whether the operation succeeded.
+
+
 
 
 
@@ -4108,11 +4586,28 @@ will be valid after the corresponding value is removed from the stack.
 <pre>lua_Number lua_tonumber (lua_State *L, int index);</pre>
 
 <p>
+A macro equivalent to <code>lua_tonumberx(L, index, NULL)</code>.
+
+
+
+
+
+<hr><h3><a name="lua_tonumberx"><code>lua_tonumberx</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>lua_Number lua_tonumberx (lua_State *L, int index, int *isnum);</pre>
+
+<p>
 Converts the Lua value at the given acceptable index
 to the C&nbsp;type <a href="#lua_Number"><code>lua_Number</code></a> (see <a href="#lua_Number"><code>lua_Number</code></a>).
 The Lua value must be a number or a string convertible to a number
-(see <a href="#2.2.1">&sect;2.2.1</a>);
-otherwise, <a href="#lua_tonumber"><code>lua_tonumber</code></a> returns&nbsp;0.
+(see <a href="#3.4.2">&sect;3.4.2</a>);
+otherwise, <a href="#lua_tonumberx"><code>lua_tonumberx</code></a> returns&nbsp;0.
+
+
+<p>
+If <code>isnum</code> is different from <code>NULL</code>,
+its referent is assigned a boolean value that
+indicates whether the operation succeeded.
 
 
 
@@ -4163,6 +4658,46 @@ otherwise, the function returns <code>NULL</code>.
 
 
 
+<hr><h3><a name="lua_tounsigned"><code>lua_tounsigned</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>lua_Unsigned lua_tounsigned (lua_State *L, int index);</pre>
+
+<p>
+A macro equivalent to <code>lua_tounsignedx(L, index, NULL)</code>.
+
+
+
+
+
+<hr><h3><a name="lua_tounsignedx"><code>lua_tounsignedx</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>lua_Unsigned lua_tounsignedx (lua_State *L, int index, int *isnum);</pre>
+
+<p>
+Converts the Lua value at the given acceptable index
+to the unsigned integral type <a href="#lua_Unsigned"><code>lua_Unsigned</code></a>.
+The Lua value must be a number or a string convertible to a number
+(see <a href="#3.4.2">&sect;3.4.2</a>);
+otherwise, <a href="#lua_tounsignedx"><code>lua_tounsignedx</code></a> returns&nbsp;0.
+
+
+<p>
+If the number is not an integer,
+it is truncated in some non-specified way.
+If the number is outside the range of representable values,
+it is normalized to the remainder of its division by
+one more than the maximum representable value.
+
+
+<p>
+If <code>isnum</code> is different from <code>NULL</code>,
+its referent is assigned a boolean value that
+indicates whether the operation succeeded.
+
+
+
+
+
 <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>
@@ -4188,16 +4723,16 @@ 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>,
+<a name="pdf-LUA_TNIL"><code>LUA_TNIL</code></a>,
+<a name="pdf-LUA_TNUMBER"><code>LUA_TNUMBER</code></a>,
+<a name="pdf-LUA_TBOOLEAN"><code>LUA_TBOOLEAN</code></a>,
+<a name="pdf-LUA_TSTRING"><code>LUA_TSTRING</code></a>,
+<a name="pdf-LUA_TTABLE"><code>LUA_TTABLE</code></a>,
+<a name="pdf-LUA_TFUNCTION"><code>LUA_TFUNCTION</code></a>,
+<a name="pdf-LUA_TUSERDATA"><code>LUA_TUSERDATA</code></a>,
+<a name="pdf-LUA_TTHREAD"><code>LUA_TTHREAD</code></a>,
 and
-<code>LUA_TLIGHTUSERDATA</code>.
+<a name="pdf-LUA_TLIGHTUSERDATA"><code>LUA_TLIGHTUSERDATA</code></a>.
 
 
 
@@ -4215,6 +4750,37 @@ which must be one the values returned by <a href="#lua_type"><code>lua_type</cod
 
 
 
+<hr><h3><a name="lua_Unsigned"><code>lua_Unsigned</code></a></h3>
+<pre>typedef unsigned long lua_Unsigned;</pre>
+
+<p>
+The type used by the Lua API to represent unsigned integral values.
+It must have at least 32 bits.
+
+
+<p>
+By default it is an <code>unsigned int</code> or an <code>unsigned long</code>,
+whichever can hold 32-bit values.
+
+
+
+
+
+<hr><h3><a name="lua_version"><code>lua_version</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>const lua_Number *lua_version (lua_State *L);</pre>
+
+<p>
+Returns the address of the version number stored in the Lua core.
+When called with a valid <a href="#lua_State"><code>lua_State</code></a>,
+returns the address of the version used to create that state.
+When called with <code>NULL</code>,
+returns the address of the version running the call.
+
+
+
+
+
 <hr><h3><a name="lua_Writer"><code>lua_Writer</code></a></h3>
 <pre>typedef int (*lua_Writer) (lua_State *L,
                            const void* p,
@@ -4245,7 +4811,7 @@ calling the writer again.
 <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.
+Exchange values between different threads of the same global state.
 
 
 <p>
@@ -4261,6 +4827,21 @@ and pushes them onto the stack <code>to</code>.
 <pre>int lua_yield  (lua_State *L, int nresults);</pre>
 
 <p>
+This function is equivalent to <a href="#lua_yieldk"><code>lua_yieldk</code></a>,
+but it has no continuation (see <a href="#4.7">&sect;4.7</a>).
+Therefore, when the thread resumes,
+it returns to the function that called
+the function calling <code>lua_yield</code>.
+
+
+
+
+
+<hr><h3><a name="lua_yieldk"><code>lua_yieldk</code></a></h3><p>
+<span class="apii">[-?, +?, <em>-</em>]</span>
+<pre>int lua_yieldk  (lua_State *L, int nresults, int ctx, lua_CFunction k);</pre>
+
+<p>
 Yields a coroutine.
 
 
@@ -4269,21 +4850,34 @@ This function should only be called as the
 return expression of a C&nbsp;function, as follows:
 
 <pre>
-     return lua_yield (L, nresults);
+     return lua_yield (L, nresults, i, k);
 </pre><p>
-When a C&nbsp;function calls <a href="#lua_yield"><code>lua_yield</code></a> in that way,
+When a C&nbsp;function calls <a href="#lua_yieldk"><code>lua_yieldk</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>.
 
 
+<p>
+When the coroutine is resumed again,
+Lua calls the given continuation function <code>k</code> to continue
+the execution of the C function that yielded (see <a href="#4.7">&sect;4.7</a>).
+This continuation function receives the same stack
+from the previous function,
+with the results removed and
+replaced by the arguments passed to <a href="#lua_resume"><code>lua_resume</code></a>.
+Moreover,
+the continuation function may access the value <code>ctx</code>
+by calling <a href="#lua_getctx"><code>lua_getctx</code></a>.
+
+
 
 
 
 
 
-<h2>3.8 - <a name="3.8">The Debug Interface</a></h2>
+<h2>4.9 &ndash; <a name="4.9">The Debug Interface</a></h2>
 
 <p>
 Lua has no built-in debugging facilities.
@@ -4303,9 +4897,12 @@ that need "inside information" from the interpreter.
   const char *what;           /* (S) */
   const char *source;         /* (S) */
   int currentline;            /* (l) */
-  int nups;                   /* (u) number of upvalues */
   int linedefined;            /* (S) */
   int lastlinedefined;        /* (S) */
+  unsigned char nups;         /* (u) number of upvalues */
+  unsigned char nparams;      /* (u) number of parameters */
+  char isvararg;              /* (u) */
+  char istailcall;            /* (t) */
   char short_src[LUA_IDSIZE]; /* (S) */
   /* private part */
   <em>other fields</em>
@@ -4313,7 +4910,7 @@ that need "inside information" from the interpreter.
 
 <p>
 A structure used to carry different pieces of
-information about an active function.
+information about a function or an activation record.
 <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,
@@ -4325,41 +4922,43 @@ The fields of <a href="#lua_Debug"><code>lua_Debug</code></a> have the following
 
 <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><b><code>source</code>: </b>
+the source of the chunk that created the function.
+If <code>source</code> starts with a '<code>@</code>',
+it means that the function was defined in a file where
+the file name follows the '<code>@</code>'.
+If <code>source</code> starts with a '<code>=</code>',
+the rest of it should describe the source in a user-dependent manner.
+Otherwise,
+the function was defined in a string where
+<code>source</code> is that string.
 </li>
 
-<li><b><code>short_src</code>:</b>
+<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>
+<li><b><code>linedefined</code>: </b>
 the line number where the definition of the function starts.
 </li>
 
-<li><b><code>lastlinedefined</code>:</b>
+<li><b><code>lastlinedefined</code>: </b>
 the line number where the definition of the function ends.
 </li>
 
-<li><b><code>what</code>:</b>
+<li><b><code>what</code>: </b>
 the string <code>"Lua"</code> if the function is a Lua function,
 <code>"C"</code> if it is a C&nbsp;function,
-<code>"main"</code> if it is the main part of a chunk,
-and <code>"tail"</code> if it was a function that did a tail call.
-In the latter case,
-Lua has no other information about the function.
+<code>"main"</code> if it is the main part of a chunk.
 </li>
 
-<li><b><code>currentline</code>:</b>
+<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>
+<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:
@@ -4371,7 +4970,7 @@ If it cannot find a name,
 then <code>name</code> is set to <code>NULL</code>.
 </li>
 
-<li><b><code>namewhat</code>:</b>
+<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>,
@@ -4380,10 +4979,25 @@ 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>
+<li><b><code>istailcall</code>: </b>
+true if this function invocation was called by a tail call.
+In this case, the caller of this level is not in the stack.
+</li>
+
+<li><b><code>nups</code>: </b>
 the number of upvalues of the function.
 </li>
 
+<li><b><code>nparams</code>: </b>
+the number of fixed parameters of the function
+(always 0&nbsp;for C&nbsp;functions).
+</li>
+
+<li><b><code>isvararg</code>: </b>
+whether the function is a vararg function
+(always true for C&nbsp;functions).
+</li>
+
 </ul>
 
 
@@ -4441,13 +5055,13 @@ given as argument to a hook (see <a href="#lua_Hook"><code>lua_Hook</code></a>).
 To get information about a function you push it onto the stack
 and start the <code>what</code> string with the character '<code>&gt;</code>'.
 (In that case,
-<code>lua_getinfo</code> pops the function in the top of the stack.)
+<code>lua_getinfo</code> pops the function from 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_getglobal(L, "f");  /* get global 'f' */
      lua_getinfo(L, "&gt;S", &amp;ar);
      printf("%d\n", ar.linedefined);
 </pre>
@@ -4459,26 +5073,30 @@ 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><b>'<code>n</code>': </b> fills in the field <code>name</code> and <code>namewhat</code>;
 </li>
 
-<li><b>'<code>S</code>':</b>
+<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><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><b>'<code>t</code>': </b> fills in the field <code>istailcall</code>;
 </li>
 
-<li><b>'<code>f</code>':</b>
+<li><b>'<code>u</code>': </b> fills in the fields
+<code>nups</code>, <code>nparams</code>, and <code>isvararg</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>
+<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,
@@ -4501,21 +5119,31 @@ This function returns 0 on error
 <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
+Gets information about a local variable of
+a given activation record or a given function.
+
+
+<p>
+In the first case,
+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).
+The index <code>n</code> selects which local variable to inspect;
+see <a href="#pdf-debug.getlocal"><code>debug.getlocal</code></a> for details about variable indices
+and names.
+
+
+<p>
 <a href="#lua_getlocal"><code>lua_getlocal</code></a> pushes the variable's value onto the stack
 and returns its name.
 
 
 <p>
-Variable names starting with '<code>(</code>' (open parentheses)
-represent internal variables
-(loop control variables, temporaries, and C&nbsp;function locals).
+In the second case, <code>ar</code> should be <code>NULL</code> and the function
+to be inspected must be at the top of the stack.
+In this case, only parameters of Lua functions are visible
+(as there is no information about what variables are active)
+and no values are pushed onto the stack.
 
 
 <p>
@@ -4540,7 +5168,8 @@ This function fills parts of a <a href="#lua_Debug"><code>lua_Debug</code></a> s
 an identification of the <em>activation record</em>
 of the function executing at a given level.
 Level&nbsp;0 is the current running function,
-whereas level <em>n+1</em> is the function that has called level <em>n</em>.
+whereas level <em>n+1</em> is the function that has called level <em>n</em>
+(except for tail calls, which do not count on the stack).
 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.
@@ -4589,16 +5218,17 @@ 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>,
+<a name="pdf-LUA_HOOKTAILCALL"><code>LUA_HOOKTAILCALL</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>
+For call events, <code>event</code> can be <code>LUA_HOOKCALL</code>,
+the normal value, or <code>LUA_HOOKTAILCALL</code>, for a tail call;
+in this case, there will be no corresponding return event.
 
 
 <p>
@@ -4632,23 +5262,24 @@ 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.
+<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.
+<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.
+There is no standard way to access the values
+to be returned by the function.
 </li>
 
-<li><b>The line hook:</b> is called when the interpreter is about to
+<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
+<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>
@@ -4705,15 +5336,50 @@ when the index is greater than the number of upvalues.
 
 
 
+<hr><h3><a name="lua_upvalueid"><code>lua_upvalueid</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>void *lua_upvalueid (lua_State *L, int funcindex, int n);</pre>
+
+<p>
+Returns an unique identifier for the upvalue numbered <code>n</code>
+from the closure at index <code>fidx</code>.
+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>)
+(but <code>n</code> cannot be greater than the number of upvalues).
+
+
+<p>
+These unique identifiers allow a program to check whether different
+closures share upvalues.
+Lua closures that share an upvalue
+(that is, that access a same external local variable)
+will return identical ids for those upvalue indices.
+
+
+
+
+
+<hr><h3><a name="lua_upvaluejoin"><code>lua_upvaluejoin</code></a></h3>
+<pre>void lua_upvaluejoin (lua_State *L, int fidx1, int n1,
+                                    int fidx2, int n2);</pre>
+
+<p>
+Make the <code>n1</code>-th upvalue of the Lua closure at index <code>fidx1</code>
+refer to the <code>n2</code>-th upvalue of the Lua closure at index <code>fidx2</code>.
+
+
 
 
-<h1>4 - <a name="4">The Auxiliary Library</a></h1>
+
+
+
+<h1>5 &ndash; <a name="5">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 
+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.
@@ -4728,21 +5394,32 @@ 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.
+and so they provide nothing that cannot be done with that API.
+
+
+<p>
+Several functions in the auxiliary library use internally some
+extra stack slots.
+When a function in the auxiliary library uses less than five slots,
+it does not check the stack size;
+it simply assumes that there are enough slots.
 
 
 <p>
 Several functions in the auxiliary library are used to
 check C&nbsp;function arguments.
-Their names are always <code>luaL_check*</code> or <code>luaL_opt*</code>.
-All of these functions throw an error if the check is not satisfied.
 Because the error message is formatted for arguments
 (e.g., "<code>bad argument #1</code>"),
 you should not use these functions for other stack values.
 
 
+<p>
+Functions called <code>luaL_check*</code>
+always throw an error if the check is not satisfied.
+
+
 
-<h2>4.1 - <a name="4.1">Functions and Types</a></h2>
+<h2>5.1 &ndash; <a name="5.1">Functions and Types</a></h2>
 
 <p>
 Here we list all functions and types from the auxiliary library
@@ -4751,7 +5428,7 @@ 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>
+<span class="apii">[-?, +?, <em>m</em>]</span>
 <pre>void luaL_addchar (luaL_Buffer *B, char c);</pre>
 
 <p>
@@ -4763,21 +5440,21 @@ Adds the character <code>c</code> to the buffer <code>B</code>
 
 
 <hr><h3><a name="luaL_addlstring"><code>luaL_addlstring</code></a></h3><p>
-<span class="apii">[-0, +0, <em>m</em>]</span>
+<span class="apii">[-?, +?, <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.
+The string can 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>
+<span class="apii">[-?, +?, <em>m</em>]</span>
 <pre>void luaL_addsize (luaL_Buffer *B, size_t n);</pre>
 
 <p>
@@ -4790,21 +5467,21 @@ 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>
+<span class="apii">[-?, +?, <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.
+The string should 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>
+<span class="apii">[-1, +?, <em>m</em>]</span>
 <pre>void luaL_addvalue (luaL_Buffer *B);</pre>
 
 <p>
@@ -4893,6 +5570,27 @@ This call leaves the final string on the top of the stack.
 </ul>
 
 <p>
+If you know beforehand the total size of the resulting string,
+you can use the buffer like this:
+
+<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 and preallocate a space of
+size <code>sz</code> with a call <code>luaL_buffinitsize(L, &amp;b, sz)</code>.</li>
+
+<li>Then you copy the string into that space.</li>
+
+<li>
+You finish by calling <code>luaL_pushresult(&amp;b, sz)</code>,
+where <code>sz</code> is the total size of the resulting string
+copied into that space.
+</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
@@ -4926,6 +5624,18 @@ the buffer must be declared as a variable
 
 
 
+<hr><h3><a name="luaL_buffinitsize"><code>luaL_buffinitsize</code></a></h3><p>
+<span class="apii">[-?, +?, <em>m</em>]</span>
+<pre>char *luaL_buffinitsize (lua_State *L, luaL_Buffer *B, size_t sz);</pre>
+
+<p>
+Equivalent to the sequence
+<a href="#luaL_buffinit"><code>luaL_buffinit</code></a>, <a href="#luaL_prepbuffsize"><code>luaL_prepbuffsize</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>
@@ -4938,10 +5648,10 @@ Calls a metamethod.
 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
+In this case this function returns true 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).
+this function returns false (without pushing any value on the stack).
 
 
 
@@ -5064,7 +5774,8 @@ to use strings instead of numbers to select options.)
 <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.
+<code>msg</code> is an additional text to go into the error message
+(or <code>NULL</code> for no additional text).
 
 
 
@@ -5105,7 +5816,36 @@ See <a href="#lua_type"><code>lua_type</code></a> for the encoding of types for
 
 <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>).
+of the type <code>tname</code> (see <a href="#luaL_newmetatable"><code>luaL_newmetatable</code></a>) and
+returns the userdata address (see <a href="#lua_touserdata"><code>lua_touserdata</code></a>).
+
+
+
+
+
+<hr><h3><a name="luaL_checkunsigned"><code>luaL_checkunsigned</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>lua_Unsigned luaL_checkunsigned (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_Unsigned"><code>lua_Unsigned</code></a>.
+
+
+
+
+
+<hr><h3><a name="luaL_checkversion"><code>luaL_checkversion</code></a></h3><p>
+<span class="apii">[-0, +0, <em>-</em>]</span>
+<pre>void luaL_checkversion (lua_State *L);</pre>
+
+<p>
+Checks whether the core running the call,
+the core that created the Lua state,
+and the code making the call are all using the same version of Lua.
+Also checks whether the core running the call
+and the core that created the Lua state
+are using the same address space.
 
 
 
@@ -5122,15 +5862,15 @@ 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.
+It returns false if there are no errors
+or true 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>
+<span class="apii">[-0, +?, <em>-</em>]</span>
 <pre>int luaL_dostring (lua_State *L, const char *str);</pre>
 
 <p>
@@ -5140,8 +5880,8 @@ 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.
+It returns false if there are no errors
+or true in case of errors.
 
 
 
@@ -5170,6 +5910,32 @@ as <code>return luaL_error(<em>args</em>)</code>.
 
 
 
+<hr><h3><a name="luaL_execresult"><code>luaL_execresult</code></a></h3><p>
+<span class="apii">[-0, +3, <em>m</em>]</span>
+<pre>int luaL_execresult (lua_State *L, int stat);</pre>
+
+<p>
+This function produces the return values for
+process-related functions in the standard library
+(<a href="#pdf-os.execute"><code>os.execute</code></a> and <a href="#pdf-io.close"><code>io.close</code></a>).
+
+
+
+
+
+<hr><h3><a name="luaL_fileresult"><code>luaL_fileresult</code></a></h3><p>
+<span class="apii">[-0, +(1|3), <em>m</em>]</span>
+<pre>int luaL_fileresult (lua_State *L, int stat, const char *fname);</pre>
+
+<p>
+This function produces the return values for
+file-related functions in the standard library
+(<a href="#pdf-io.open"><code>io.open</code></a>, <a href="#pdf-os.rename"><code>os.rename</code></a>, <a href="#pdf-file:seek"><code>file:seek</code></a>, etc.).
+
+
+
+
+
 <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>
@@ -5179,7 +5945,7 @@ 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.
+returns false and pushes nothing.
 
 
 
@@ -5197,6 +5963,22 @@ in the registry (see <a href="#luaL_newmetatable"><code>luaL_newmetatable</code>
 
 
 
+<hr><h3><a name="luaL_getsubtable"><code>luaL_getsubtable</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>int luaL_getsubtable (lua_State *L, int idx, const char *fname);</pre>
+
+<p>
+Ensures that the value <code>t[fname]</code>,
+where <code>t</code> is the value at the valid index <code>idx</code>,
+is a table,
+and pushes that table onto the stack.
+Returns true if it finds a previous table there
+and false if it creates a new table.
+
+
+
+
+
 <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,
@@ -5214,8 +5996,23 @@ Pushes the resulting string on the stack and returns it.
 
 
 
+<hr><h3><a name="luaL_len"><code>luaL_len</code></a></h3><p>
+<span class="apii">[-0, +1, <em>e</em>]</span>
+<pre>int luaL_len (lua_State *L, int index);</pre>
+
+<p>
+Returns the "length" of the value at the given acceptable index
+as a number;
+it is equivalent to the '<code>#</code>' operator in Lua (see <a href="#3.4.6">&sect;3.4.6</a>).
+Raises an error if the result of the operation is not a number.
+(This only can happen through metamethods.)
+
+
+
+
+
 <hr><h3><a name="luaL_loadbuffer"><code>luaL_loadbuffer</code></a></h3><p>
-<span class="apii">[-0, +1, <em>m</em>]</span>
+<span class="apii">[-0, +1, <em>-</em>]</span>
 <pre>int luaL_loadbuffer (lua_State *L,
                      const char *buff,
                      size_t sz,
@@ -5264,7 +6061,7 @@ 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>
+<span class="apii">[-0, +1, <em>-</em>]</span>
 <pre>int luaL_loadstring (lua_State *L, const char *s);</pre>
 
 <p>
@@ -5285,6 +6082,43 @@ it does not run it.
 
 
 
+<hr><h3><a name="luaL_newlib"><code>luaL_newlib</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>int luaL_newlib (lua_State *L, const luaL_Reg *l);</pre>
+
+<p>
+Creates a new table and registers there
+the functions in list <code>l</code>.
+It is implemented as the following macro:
+
+<pre>
+     (luaL_newlibtable(L,l), luaL_setfuncs(L,l,0))
+</pre>
+
+
+
+
+<hr><h3><a name="luaL_newlibtable"><code>luaL_newlibtable</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>int luaL_newlibtable (lua_State *L, const luaL_Reg l[]);</pre>
+
+<p>
+Creates a new table with a size optimized
+to store all entries in the array <code>l</code>
+(but does not actually store them).
+It is intended to be used in conjunction with <a href="#luaL_setfuncs"><code>luaL_setfuncs</code></a>
+(see <a href="#luaL_newlib"><code>luaL_newlib</code></a>).
+
+
+<p>
+It is implemented as a macro.
+The array <code>l</code> must be the actual array,
+not a pointer to 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>
@@ -5314,7 +6148,7 @@ with <code>tname</code> in the registry.
 Creates a new Lua state.
 It calls <a href="#lua_newstate"><code>lua_newstate</code></a> with an
 allocator based on the standard&nbsp;C <code>realloc</code> function
-and then sets a panic function (see <a href="#lua_atpanic"><code>lua_atpanic</code></a>) that prints
+and then sets a panic function (see <a href="#4.6">&sect;4.6</a>) that prints
 an error message to the standard error output in case of fatal
 errors.
 
@@ -5328,7 +6162,7 @@ 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>
+<span class="apii">[-0, +0, <em>e</em>]</span>
 <pre>void luaL_openlibs (lua_State *L);</pre>
 
 <p>
@@ -5402,7 +6236,7 @@ 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.
+fills the position <code>*l</code> with the result's length.
 
 
 
@@ -5440,16 +6274,45 @@ Otherwise, raises an error.
 
 
 
+<hr><h3><a name="luaL_optunsigned"><code>luaL_optunsigned</code></a></h3><p>
+<span class="apii">[-0, +0, <em>v</em>]</span>
+<pre>lua_Unsigned luaL_optunsigned (lua_State *L,
+                               int narg,
+                               lua_Unsigned u);</pre>
+
+<p>
+If the function argument <code>narg</code> is a number,
+returns this number cast to a <a href="#lua_Unsigned"><code>lua_Unsigned</code></a>.
+If this argument is absent or is <b>nil</b>,
+returns <code>u</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>
+<span class="apii">[-?, +?, <em>m</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>
+Equivalent to <a href="#luaL_prepbuffsize"><code>luaL_prepbuffsize</code></a>
+with the predefined size <a name="pdf-LUAL_BUFFERSIZE"><code>LUAL_BUFFERSIZE</code></a>.
+
+
+
+
+
+<hr><h3><a name="luaL_prepbuffsize"><code>luaL_prepbuffsize</code></a></h3><p>
+<span class="apii">[-?, +?, <em>m</em>]</span>
+<pre>char *luaL_prepbuffsize (luaL_Buffer *B, size_t sz);</pre>
+
+<p>
+Returns an address to a space of size <code>sz</code>
 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 
+<a href="#luaL_addsize"><code>luaL_addsize</code></a> with the size of the string to actually add
 it to the buffer.
 
 
@@ -5468,6 +6331,17 @@ the top of the stack.
 
 
 
+<hr><h3><a name="luaL_pushresultsize"><code>luaL_pushresultsize</code></a></h3><p>
+<span class="apii">[-?, +1, <em>m</em>]</span>
+<pre>void luaL_pushresultsize (luaL_Buffer *B, size_t sz);</pre>
+
+<p>
+Equivalent to the sequence <a href="#luaL_addsize"><code>luaL_addsize</code></a>, <a href="#luaL_pushresult"><code>luaL_pushresult</code></a>.
+
+
+
+
+
 <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>
@@ -5505,7 +6379,7 @@ from any reference returned by <a href="#luaL_ref"><code>luaL_ref</code></a>.
 
 <p>
 Type for arrays of functions to be registered by
-<a href="#luaL_register"><code>luaL_register</code></a>.
+<a href="#luaL_setfuncs"><code>luaL_setfuncs</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
@@ -5515,65 +6389,121 @@ 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>
+<hr><h3><a name="luaL_requiref"><code>luaL_requiref</code></a></h3><p>
+<span class="apii">[-0, +1, <em>e</em>]</span>
+<pre>void luaL_requiref (lua_State *L, const char *modname,
+                    lua_CFunction openf, int glb);</pre>
 
 <p>
-Opens a library.
+Calls function <code>openf</code> with string <code>modname</code> as an argument
+and sets the call result in <code>package.loaded[modname]</code>,
+as if that function has been called through <a href="#pdf-require"><code>require</code></a>.
 
 
 <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.
+If <code>glb</code> is true,
+also stores the result into global <code>modname</code>.
 
 
 <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.
+Leaves a copy of that result on the stack.
+
 
 
+
+
+<hr><h3><a name="luaL_setfuncs"><code>luaL_setfuncs</code></a></h3><p>
+<span class="apii">[-nup, +0, <em>e</em>]</span>
+<pre>void luaL_setfuncs (lua_State *L, const luaL_Reg *l, int nup);</pre>
+
 <p>
-In any case the function leaves the table
-on the top of the stack.
+Registers all functions in the array <code>l</code>
+(see <a href="#luaL_Reg"><code>luaL_Reg</code></a>) into the table on the top of the stack
+(below optional upvalues, see next).
 
 
+<p>
+When <code>nup</code> is not zero,
+all functions are created sharing <code>nup</code> upvalues,
+which must be previously pushed on the stack
+on top of the library table.
+These values are popped from the stack after the registration.
 
 
 
-<hr><h3><a name="luaL_typename"><code>luaL_typename</code></a></h3><p>
+
+
+<hr><h3><a name="luaL_setmetatable"><code>luaL_setmetatable</code></a></h3><p>
 <span class="apii">[-0, +0, <em>-</em>]</span>
-<pre>const char *luaL_typename (lua_State *L, int index);</pre>
+<pre>void luaL_setmetatable (lua_State *L, const char *tname);</pre>
 
 <p>
-Returns the name of the type of the value at the given index.
+Sets the metatable of the object at the top of the stack
+as 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_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>
+<hr><h3><a name="luaL_testudata"><code>luaL_testudata</code></a></h3><p>
+<span class="apii">[-0, +0, <em>m</em>]</span>
+<pre>void *luaL_testudata (lua_State *L, int narg, const char *tname);</pre>
 
 <p>
-Generates an error with a message like the following:
+This function works like <a href="#luaL_checkudata"><code>luaL_checkudata</code></a>,
+except that, when the test fails,
+it returns <code>NULL</code> instead of throwing an error.
 
-<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_tolstring"><code>luaL_tolstring</code></a></h3><p>
+<span class="apii">[-0, +1, <em>e</em>]</span>
+<pre>const char *luaL_tolstring (lua_State *L, int idx, size_t *len);</pre>
+
+<p>
+Converts any Lua value at the given acceptable index to a C&nbsp;string
+in a reasonable format.
+The resulting string is pushed onto the stack and also
+returned by the function.
+If <code>len</code> is not <code>NULL</code>,
+the function also sets <code>*len</code> with the string length.
+
+
+<p>
+If the value has a metatable with a <code>"__tostring"</code> field,
+then <code>luaL_tolstring</code> calls the corresponding metamethod
+with the value as argument,
+and uses the result of the call as its result.
+
+
+
+
+
+<hr><h3><a name="luaL_traceback"><code>luaL_traceback</code></a></h3><p>
+<span class="apii">[-0, +1, <em>m</em>]</span>
+<pre>void luaL_traceback (lua_State *L, lua_State *L1, const char *msg,
+                     int level);</pre>
+
+<p>
+Creates and pushes a traceback of the stack <code>L1</code>.
+If <code>msg</code> is not <code>NULL</code> it is appended
+at the beginning of the traceback.
+The <code>level</code> parameter tells at which level
+to start the traceback.
+
+
+
+
+
+<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.
 
 
 
@@ -5625,7 +6555,7 @@ This function is used to build a prefix for error messages.
 
 
 
-<h1>5 - <a name="5">Standard Libraries</a></h1>
+<h1>6 &ndash; <a name="6">Standard Libraries</a></h1>
 
 <p>
 The standard Lua libraries provide useful functions
@@ -5645,16 +6575,20 @@ Currently, Lua has the following standard libraries:
 
 <ul>
 
-<li>basic library,</li> which includes the coroutine sub-library;
+<li>basic library;</li>
 
 <li>package library;</li>
 
+<li>coroutine library;</li>
+
 <li>string manipulation;</li>
 
 <li>table manipulation;</li>
 
 <li>mathematical functions (sin, log, etc.);</li>
 
+<li>bitwise operations;</li>
+
 <li>input and output;</li>
 
 <li>operating system facilities;</li>
@@ -5675,9 +6609,11 @@ 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_coroutine"><code>luaopen_coroutine</code></a> (for the coroutine 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_bitlib"><code>luaopen_bitlib</code></a> (for the bit 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).
@@ -5688,12 +6624,12 @@ e.g., by using <a href="#lua_call"><code>lua_call</code></a>.
 
 
 
-<h2>5.1 - <a name="5.1">Basic Functions</a></h2>
+<h2>6.1 &ndash; <a name="6.1">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 
+you should check carefully whether you need to provide
 implementations for some of its facilities.
 
 
@@ -5709,7 +6645,7 @@ when absent, it defaults to "assertion failed!"
 
 
 <p>
-<hr><h3><a name="pdf-collectgarbage"><code>collectgarbage (opt [, arg])</code></a></h3>
+<hr><h3><a name="pdf-collectgarbage"><code>collectgarbage ([opt [, arg]])</code></a></h3>
 
 
 <p>
@@ -5718,23 +6654,36 @@ It performs different functions according to its first argument, <code>opt</code
 
 <ul>
 
-<li><b>"stop":</b>
-stops the garbage collector.
+<li><b>"<code>collect</code>": </b>
+performs a full garbage-collection cycle.
+This is the default option.
 </li>
 
-<li><b>"restart":</b>
-restarts the garbage collector.
+<li><b>"<code>stop</code>": </b>
+stops automatic invocation of the garbage collector.
+The collector will run only when explcitly invoked,
+until a call to restart it.
 </li>
 
-<li><b>"collect":</b>
-performs a full garbage-collection cycle.
+<li><b>"<code>restart</code>": </b>
+restarts automatic invocation the garbage collector.
 </li>
 
-<li><b>"count":</b>
-returns the total memory in use by Lua (in Kbytes).
+<li><b>"<code>count</code>": </b>
+returns the total memory in use by Lua (in Kbytes) and
+a second value with the total memory in bytes modulo 1024.
+The first value has a fractional part,
+so the following equality is always true:
+
+<pre>
+     k, b = collectgarbage("count")
+     assert(k*1024 == math.floor(k)*1024 + b)
+</pre><p>
+(The second result is useful when Lua is compiled
+with a non floating-point type for numbers.)
 </li>
 
-<li><b>"step":</b>
+<li><b>"<code>step</code>": </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.
@@ -5743,24 +6692,29 @@ 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>
+<li><b>"<code>setpause</code>": </b>
 sets <code>arg</code> as the new value for the <em>pause</em> of
-the collector (see <a href="#2.10">&sect;2.10</a>).
+the collector (see <a href="#2.5">&sect;2.5</a>).
 Returns the previous value for <em>pause</em>.
 </li>
 
-<li><b>"setstepmul":</b>
+<li><b>"<code>setstepmul</code>": </b>
 sets <code>arg</code> as the new value for the <em>step multiplier</em> of
-the collector (see <a href="#2.10">&sect;2.10</a>).
+the collector (see <a href="#2.5">&sect;2.5</a>).
 Returns the previous value for <em>step</em>.
 </li>
 
+<li><b>"<code>isrunning</code>": </b>
+returns a boolean that tells whether the collector is running
+(i.e., not stopped).
+</li>
+
 </ul>
 
 
 
 <p>
-<hr><h3><a name="pdf-dofile"><code>dofile (filename)</code></a></h3>
+<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>).
@@ -5780,7 +6734,7 @@ Function <code>error</code> never returns.
 
 <p>
 Usually, <code>error</code> adds some information about the error position
-at the beginning of the message.
+at the beginning of the message, if the message is a string.
 The <code>level</code> argument specifies how to get the error position.
 With level&nbsp;1 (the default), the error position is where the
 <code>error</code> function was called.
@@ -5795,25 +6749,10 @@ 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>).
+holds the global environment (see <a href="#2.2">&sect;2.2</a>).
 Lua itself does not use this variable;
 changing its value does not affect any environment,
 nor vice-versa.
-(Use <a href="#pdf-setfenv"><code>setfenv</code></a> to change environments.)
-
-
-
-
-<p>
-<hr><h3><a name="pdf-getfenv"><code>getfenv ([f])</code></a></h3>
-Returns the current environment in use by the function.
-<code>f</code> can be a Lua function or a number
-that specifies the function at that stack level:
-Level&nbsp;1 is the function calling <code>getfenv</code>.
-If the given function is not a Lua function,
-or if <code>f</code> is 0,
-<code>getfenv</code> returns the global environment.
-The default for <code>f</code> is 1.
 
 
 
@@ -5837,7 +6776,14 @@ Otherwise, returns the metatable of the given object.
 
 
 <p>
-Returns three values: an iterator function, the table <code>t</code>, and 0,
+If <code>t</code> has a metamethod <code>__ipairs</code>,
+calls it with <code>t</code> as argument and returns the first three
+results from the call.
+
+
+<p>
+Otherwise,
+returns three values: an iterator function, the table <code>t</code>, and 0,
 so that the construction
 
 <pre>
@@ -5850,64 +6796,64 @@ up to the first integer key absent from the table.
 
 
 <p>
-<hr><h3><a name="pdf-load"><code>load (func [, chunkname])</code></a></h3>
+<hr><h3><a name="pdf-load"><code>load (ld [, source [, mode [, env]]])</code></a></h3>
+
+
+<p>
+Loads a chunk.
 
 
 <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
+If <code>ld</code> is a string, the chunk is this string.
+If <code>ld</code> is a function,
+<code>load</code> calls it repeatedly to get the chunk pieces.
+Each call to <code>ld</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, 
+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>".
-
-
+If the resulting function has upvalues,
+the first upvalue is set to the value of the
+global environment or to <code>env</code>,
+if that parameter is given.
+(When loading main chunks,
+the first upvalue will be the <code>_ENV</code> variable (see <a href="#2.2">&sect;2.2</a>).)
 
 
 <p>
-<hr><h3><a name="pdf-loadfile"><code>loadfile ([filename])</code></a></h3>
+<code>source</code> is used as the source of the chunk for error messages
+and debug information (see <a href="#4.9">&sect;4.9</a>).
+When absent,
+it defaults to <code>ld</code>, if <code>ld</code> is a string,
+or to "<code>=(load)</code>".
 
 
 <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.
+The string <code>mode</code> controls whether the chunk can be text or binary
+(that is, a precompiled chunk).
+A letter '<code>t</code>' in <code>mode</code> allows a text chunk;
+a letter '<code>b</code>' allows a binary chunk.
+The default is "<code>bt</code>".
 
 
 
 
 <p>
-<hr><h3><a name="pdf-loadstring"><code>loadstring (string [, chunkname])</code></a></h3>
+<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 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.
+but gets the chunk from file <code>filename</code>
+or from the standard input,
+if no file name is given.
 
 
 
@@ -5937,11 +6883,11 @@ you can use <code>next(t)</code> to check whether a table is empty.
 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.)
+use a numerical <b>for</b>.)
 
 
 <p>
-The behavior of <code>next</code> is <em>undefined</em> if,
+The behavior of <code>next</code> is undefined if,
 during the traversal,
 you assign any value to a non-existent field in the table.
 You may however modify existing fields.
@@ -5955,7 +6901,14 @@ In particular, you may clear existing fields.
 
 
 <p>
-Returns three values: the <a href="#pdf-next"><code>next</code></a> function, the table <code>t</code>, and <b>nil</b>,
+If <code>t</code> has a metamethod <code>__pairs</code>,
+calls it with <code>t</code> as argument and returns the first three
+results from the call.
+
+
+<p>
+Otherwise,
+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>
@@ -5972,7 +6925,7 @@ the table during its traversal.
 
 
 <p>
-<hr><h3><a name="pdf-pcall"><code>pcall (f, arg1, &middot;&middot;&middot;)</code></a></h3>
+<hr><h3><a name="pdf-pcall"><code>pcall (f [, arg1, &middot;&middot;&middot;])</code></a></h3>
 
 
 <p>
@@ -6023,6 +6976,16 @@ without invoking any metamethod.
 
 
 <p>
+<hr><h3><a name="pdf-rawlen"><code>rawlen (v)</code></a></h3>
+Returns the length of the object <code>v</code>,
+which must be a table or a string,
+without invoking any metamethod.
+Returns an integer number.
+
+
+
+
+<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.
@@ -6043,7 +7006,8 @@ This function returns <code>table</code>.
 
 <p>
 If <code>index</code> is a number,
-returns all arguments after argument number <code>index</code>.
+returns all arguments after argument number <code>index</code>;
+a negative number indexes from the end (-1 is the last argument).
 Otherwise, <code>index</code> must be the string <code>"#"</code>,
 and <code>select</code> returns the total number of extra arguments it received.
 
@@ -6051,26 +7015,6 @@ and <code>select</code> returns the total number of extra arguments it received.
 
 
 <p>
-<hr><h3><a name="pdf-setfenv"><code>setfenv (f, table)</code></a></h3>
-
-
-<p>
-Sets the environment to be used by the given function.
-<code>f</code> can be a Lua function or a number
-that specifies the function at that stack level:
-Level&nbsp;1 is the function calling <code>setfenv</code>.
-<code>setfenv</code> returns the given function.
-
-
-<p>
-As a special case, when <code>f</code> is 0 <code>setfenv</code> changes
-the environment of the running thread.
-In this case, <code>setfenv</code> returns no values.
-
-
-
-
-<p>
 <hr><h3><a name="pdf-setmetatable"><code>setmetatable (table, metatable)</code></a></h3>
 
 
@@ -6103,9 +7047,9 @@ The base may be any integer between 2 and 36, inclusive.
 In bases above&nbsp;10, the letter '<code>A</code>' (in either upper or lower case)
 represents&nbsp;10, '<code>B</code>' represents&nbsp;11, and so forth,
 with '<code>Z</code>' representing 35.
-In base 10 (the default), the number can have a decimal part,
-as well as an optional exponent part (see <a href="#2.1">&sect;2.1</a>).
-In other bases, only unsigned integers are accepted.
+In base 10 (the default),
+the numeral is converted following the coercion rules (see <a href="#3.4.2">&sect;3.4.2</a>).
+In other bases, only integers are accepted.
 
 
 
@@ -6144,52 +7088,21 @@ and "<code>userdata</code>".
 
 
 <p>
-<hr><h3><a name="pdf-unpack"><code>unpack (list [, i [, j]])</code></a></h3>
-Returns the elements from the given table.
-This function is equivalent to
-
-<pre>
-     return list[i], list[i+1], &middot;&middot;&middot;, list[j]
-</pre><p>
-except that the above code can be written only for a fixed number
-of elements.
-By default, <code>i</code> is&nbsp;1 and <code>j</code> is the length of the list,
-as defined by the length operator (see <a href="#2.5.5">&sect;2.5.5</a>).
-
-
-
-
-<p>
 <hr><h3><a name="pdf-_VERSION"><code>_VERSION</code></a></h3>
 A global variable (not a function) that
 holds a string containing the current interpreter version.
-The current contents of this variable is "<code>Lua 5.1</code>".
+The current contents of this variable is "<code>Lua 5.2</code>".
 
 
 
 
 <p>
-<hr><h3><a name="pdf-xpcall"><code>xpcall (f, err)</code></a></h3>
+<hr><h3><a name="pdf-xpcall"><code>xpcall (f, msgh [, arg1, &middot;&middot;&middot;])</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>.
+except that it sets a new message handler <code>msgh</code>.
 
 
 
@@ -6197,12 +7110,12 @@ In case of any error,
 
 
 
-<h2>5.2 - <a name="5.2">Coroutine Manipulation</a></h2>
+<h2>6.2 &ndash; <a name="6.2">Coroutine Manipulation</a></h2>
 
 <p>
 The operations related to coroutines comprise a sub-library of
 the basic library and come inside the table <a name="pdf-coroutine"><code>coroutine</code></a>.
-See <a href="#2.11">&sect;2.11</a> for a general description of coroutines.
+See <a href="#2.6">&sect;2.6</a> for a general description of coroutines.
 
 
 <p>
@@ -6250,8 +7163,8 @@ If there is any error,
 
 
 <p>
-Returns the running coroutine,
-or <b>nil</b> when called by the main thread.
+Returns the running coroutine plus a boolean,
+true when the running coroutine is the main one.
 
 
 
@@ -6297,8 +7210,6 @@ In case of error, propagates the error.
 
 <p>
 Suspends the execution of the calling coroutine.
-The coroutine cannot be running a C&nbsp;function,
-a metamethod, or an iterator.
 Any arguments to <code>yield</code> are passed as extra results to <code>resume</code>.
 
 
@@ -6307,57 +7218,17 @@ Any arguments to <code>yield</code> are passed as extra results to <code>resume<
 
 
 
-<h2>5.3 - <a name="5.3">Modules</a></h2>
+<h2>6.3 &ndash; <a name="6.3">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>.
+facilities for loading modules in Lua.
+It exports one function directly in the global environment:
+<a href="#pdf-require"><code>require</code></a>.
 Everything else is exported in a table <a name="pdf-package"><code>package</code></a>.
 
 
 <p>
-<hr><h3><a name="pdf-module"><code>module (name [, &middot;&middot;&middot;])</code></a></h3>
-
-
-<p>
-Creates a module.
-If there is a table in <code>package.loaded[name]</code>,
-this table is the module.
-Otherwise, if there is a global table <code>t</code> with the given name,
-this table is the module.
-Otherwise creates a new table <code>t</code> and
-sets it as the value of the global <code>name</code> and
-the value of <code>package.loaded[name]</code>.
-This function also initializes <code>t._NAME</code> with the given name,
-<code>t._M</code> with the module (<code>t</code> itself),
-and <code>t._PACKAGE</code> with the package name
-(the full module name minus last component; see below).
-Finally, <code>module</code> sets <code>t</code> as the new environment
-of the current function and the new value of <code>package.loaded[name]</code>,
-so that <a href="#pdf-require"><code>require</code></a> returns <code>t</code>.
-
-
-<p>
-If <code>name</code> is a compound name
-(that is, one with components separated by dots),
-<code>module</code> creates (or reuses, if they already exist)
-tables for each component.
-For instance, if <code>name</code> is <code>a.b.c</code>,
-then <code>module</code> stores the module table in field <code>c</code> of
-field <code>b</code> of global <code>a</code>.
-
-
-<p>
-This function 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>
 
 
@@ -6372,11 +7243,11 @@ 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,
+<code>require</code> is guided by the <a href="#pdf-package.searchers"><code>package.searchers</code></a> sequence.
+By changing this sequence,
 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>.
+for <a href="#pdf-package.searchers"><code>package.searchers</code></a>.
 
 
 <p>
@@ -6388,15 +7259,18 @@ path stored in <a href="#pdf-package.path"><code>package.path</code></a>.
 If that also fails, it searches for a C&nbsp;loader using the
 path stored in <a href="#pdf-package.cpath"><code>package.cpath</code></a>.
 If that also fails,
-it tries an <em>all-in-one</em> loader (see <a href="#pdf-package.loaders"><code>package.loaders</code></a>).
+it tries an <em>all-in-one</em> loader (see <a href="#pdf-package.searchers"><code>package.searchers</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> calls the loader with two arguments:
+<code>modname</code> and an extra value dependent on how it got the loader.
+(If the loader came from a file,
+this extra value is the file name.)
+If the loader returns any non-nil value,
 <code>require</code> assigns the returned value to <code>package.loaded[modname]</code>.
-If the loader returns no value and
+If the loader does not return a non-nil 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
@@ -6406,10 +7280,42 @@ 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. 
+then <code>require</code> signals an error.
+
 
 
 
+<p>
+<hr><h3><a name="pdf-package.config"><code>package.config</code></a></h3>
+
+
+<p>
+A string describing some compile-time configurations for packages.
+This string is a sequence of lines:
+
+<ul>
+
+<li>The first line is the directory separator string.
+Default is '<code>\</code>' for Windows and '<code>/</code>' for all other systems.</li>
+
+<li>The second line is the character that separates templates in a path.
+Default is '<code>;</code>'.</li>
+
+<li>The third line is the string that marks the
+substitution points in a template.
+Default is '<code>?</code>'.</li>
+
+<li>The fourth line is a string that, in a path in Windows,
+is replaced by the executable's directory.
+Default is '<code>!</code>'.</li>
+
+<li>The fifth line is a mark to ignore all before it when building the
+<code>luaopen_</code> function name.
+Default is '<code>-</code>'.</li>
+
+</ul>
+
+
 
 <p>
 <hr><h3><a name="pdf-package.cpath"><code>package.cpath</code></a></h3>
@@ -6422,7 +7328,8 @@ The path used by <a href="#pdf-require"><code>require</code></a> to search for a
 <p>
 Lua initializes the C&nbsp;path <a href="#pdf-package.cpath"><code>package.cpath</code></a> in the same way
 it initializes the Lua path <a href="#pdf-package.path"><code>package.path</code></a>,
-using the environment variable <a name="pdf-LUA_CPATH"><code>LUA_CPATH</code></a>
+using the environment variable <a name="pdf-LUA_CPATH_5_2"><code>LUA_CPATH_5_2</code></a>
+or the environment variable <a name="pdf-LUA_CPATH"><code>LUA_CPATH</code></a>
 or a default path defined in <code>luaconf.h</code>.
 
 
@@ -6441,10 +7348,93 @@ When you require a module <code>modname</code> and
 <a href="#pdf-require"><code>require</code></a> simply returns the value stored there.
 
 
+<p>
+This variable is only a reference to the real table;
+assignments to this variable do not change the
+table used by <a href="#pdf-require"><code>require</code></a>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-package.loadlib"><code>package.loadlib (libname, funcname)</code></a></h3>
+
+
+<p>
+Dynamically links the host program with the C&nbsp;library <code>libname</code>.
+
+
+<p>
+If <code>funcname</code> is "<code>*</code>",
+then it only links with the library,
+making the symbols exported by the library
+available to other dynamically linked libraries.
+Otherwise,
+it looks for a function <code>funcname</code> inside the library
+and returns this function as a C&nbsp;function.
+(So, <code>funcname</code> must follow the protocol (see <a href="#lua_CFunction"><code>lua_CFunction</code></a>)).
+
+
+<p>
+This is a low-level function.
+It completely bypasses the package and module system.
+Unlike <a href="#pdf-require"><code>require</code></a>,
+it does not perform any path searching and
+does not automatically adds extensions.
+<code>libname</code> must be the complete file name of the C&nbsp;library,
+including if necessary a path and an extension.
+<code>funcname</code> must be the exact name exported by the C&nbsp;library
+(which may depend on the C&nbsp;compiler and linker used).
+
+
+<p>
+This function is not supported by Standard&nbsp;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>
-<hr><h3><a name="pdf-package.loaders"><code>package.loaders</code></a></h3>
+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_5_2"><code>LUA_PATH_5_2</code></a> or
+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>
+This variable is only a reference to the real table;
+assignments to this variable do not change the
+table used by <a href="#pdf-require"><code>require</code></a>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-package.searchers"><code>package.searchers</code></a></h3>
 
 
 <p>
@@ -6458,9 +7448,13 @@ When looking for a module,
 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>)
+plus an extra value that will be passed to that loader,
 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>
+Lua initializes this table with four searcher functions.
 
 
 <p>
@@ -6471,27 +7465,14 @@ The first searcher simply looks for a loader in the
 <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.
+The search is done as described in function <a href="#pdf-package.searchpath"><code>package.searchpath</code></a>.
 
 
 <p>
 The third searcher looks for a loader as a C&nbsp;library,
 using the path given by the variable <a href="#pdf-package.cpath"><code>package.cpath</code></a>.
+Again,
+the search is done as described in function <a href="#pdf-package.searchpath"><code>package.searchpath</code></a>.
 For instance,
 if the C&nbsp;path is the string
 
@@ -6529,80 +7510,54 @@ into one single library,
 with each submodule keeping its original open function.
 
 
-
-
-<p>
-<hr><h3><a name="pdf-package.loadlib"><code>package.loadlib (libname, funcname)</code></a></h3>
-
-
-<p>
-Dynamically links the host program with the C&nbsp;library <code>libname</code>.
-Inside this library, looks for a function <code>funcname</code>
-and returns this function as a C&nbsp;function.
-(So, <code>funcname</code> must follow the protocol (see <a href="#lua_CFunction"><code>lua_CFunction</code></a>)).
-
-
 <p>
-This is a low-level function.
-It completely bypasses the package and module system.
-Unlike <a href="#pdf-require"><code>require</code></a>,
-it does not perform any path searching and
-does not automatically adds extensions.
-<code>libname</code> must be the complete file name of the C&nbsp;library,
-including if necessary a path and extension.
-<code>funcname</code> must be the exact name exported by the C&nbsp;library
-(which may depend on the C&nbsp;compiler and linker used).
-
-
-<p>
-This function is not supported by ANSI C.
-As such, it is only available on some platforms
-(Windows, Linux, Mac OS X, Solaris, BSD,
-plus other Unix systems that support the <code>dlfcn</code> standard).
-
+All searchers except the first (preload) return as the extra value
+the file name where the module was found,
+as returned by <a href="#pdf-package.searchpath"><code>package.searchpath</code></a>.
+The first searcher returns no extra value.
 
 
 
-<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.
+<hr><h3><a name="pdf-package.searchpath"><code>package.searchpath (name, path [, sep])</code></a></h3>
 
 
 <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.
-
-
+Searches for the given <code>name</code> in the given <code>path</code>.
 
 
 <p>
-<hr><h3><a name="pdf-package.preload"><code>package.preload</code></a></h3>
+A path is string containing a sequence of
+<em>templates</em> separated by semicolons.
+For each template,
+the function changes each interrogation
+mark in the template by a copy of <code>name</code>
+wherein all occurrences of <code>sep</code>
+(a dot, by default)
+were replaced by the system's directory separator,
+and then tries to open the resulting file name.
+If <code>sep</code> is the empty string,
+the replacement is not done.
 
 
 <p>
-A table to store loaders for specific modules
-(see <a href="#pdf-require"><code>require</code></a>).
-
+For instance, if the path is the string
 
+<pre>
+     "./?.lua;./?.lc;/usr/local/?/init.lua"
+</pre><p>
+the search for the name <code>foo.a</code>
+will try to open the files
+<code>./foo/a.lua</code>, <code>./foo/a.lc</code>, and
+<code>/usr/local/foo/a/init.lua</code>, in that order.
 
 
 <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>.
+Returns the resulting name of the first file that it can
+open in read mode (after closing the file),
+or <b>nil</b> plus an error message if none succeeds.
+(This error message lists all file names it tried to open.)
 
 
 
@@ -6610,7 +7565,7 @@ 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>
+<h2>6.4 &ndash; <a name="6.4">String Manipulation</a></h2>
 
 <p>
 This library provides generic functions for string manipulation,
@@ -6670,15 +7625,17 @@ Note that numerical codes are not necessarily portable across platforms.
 
 <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.
+so that a later <a href="#pdf-load"><code>load</code></a> on this string returns
+a copy of the function (but with new upvalues).
 
 
 
 
 <p>
 <hr><h3><a name="pdf-string.find"><code>string.find (s, pattern [, init [, plain]])</code></a></h3>
+
+
+<p>
 Looks for the first match of
 <code>pattern</code> in the string <code>s</code>.
 If it finds a match, then <code>find</code> returns the indices of&nbsp;<code>s</code>
@@ -6690,7 +7647,7 @@ its default value is&nbsp;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".
+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.
 
 
@@ -6705,26 +7662,25 @@ after the two indices.
 
 <p>
 <hr><h3><a name="pdf-string.format"><code>string.format (formatstring, &middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
 Returns a formatted version of its variable number of arguments
 following the description given in its first argument (which must be a string).
-The format string follows the same rules as the <code>printf</code> family of
-standard C&nbsp;functions.
+The format string follows the same rules as the C&nbsp;function <code>sprintf</code>.
 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
+<code>*</code>, <code>h</code>, <code>L</code>, <code>l</code>, <code>n</code>,
+and <code>p</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.
+The <code>q</code> option formats a string between double quotes,
+using escape sequences when necessary to ensure that
+it can safely be read back by the Lua interpreter.
 For instance, the call
 
 <pre>
      string.format('%q', 'a string with "quotes" and \n new line')
 </pre><p>
-will produce the string:
+may produce the string:
 
 <pre>
      "a string with \"quotes\" and \
@@ -6732,16 +7688,19 @@ will produce the string:
 </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.
+Options
+<code>A</code> and <code>a</code> (when available),
+<code>E</code>, <code>e</code>, <code>f</code>,
+<code>G</code>, and <code>g</code> all expect a number as argument.
+Options <code>c</code>, <code>d</code>,
+<code>i</code>, <code>o</code>, <code>u</code>, <code>X</code>, and <code>x</code>
+expect an integer as argument;
+the range of that integer may be limited by
+the underlying C&nbsp;implementation.
+Option <code>q</code> expects a string;
+option <code>s</code> expects a string without embedded zeros.
+If the argument to option <code>s</code> is not a string,
+it is converted to one following the same rules of <a href="#pdf-tostring"><code>tostring</code></a>.
 
 
 
@@ -6757,6 +7716,8 @@ then the whole match is produced in each call.
 
 <p>
 As an example, the following loop
+will iterate over all the words from string <code>s</code>,
+printing one per line:
 
 <pre>
      s = "hello world from Lua"
@@ -6764,8 +7725,6 @@ As an example, the following loop
        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:
 
@@ -6793,14 +7752,15 @@ 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.
+The name <code>gsub</code> comes from <em>Global SUBstitution</em>.
 
 
 <p>
 If <code>repl</code> is a string, then its value is used for replacement.
 The character&nbsp;<code>%</code> works as an escape character:
-any sequence in <code>repl</code> of the form <code>%<em>n</em></code>,
-with <em>n</em> between 1 and 9,
-stands for the value of the <em>n</em>-th captured substring (see below).
+any sequence in <code>repl</code> of the form <code>%<em>d</em></code>,
+with <em>d</em> between 1 and 9,
+stands for the value of the <em>d</em>-th captured substring (see below).
 The sequence <code>%0</code> stands for the whole match.
 The sequence <code>%%</code> stands for a single&nbsp;<code>%</code>.
 
@@ -6846,13 +7806,13 @@ Here are some examples:
      --&gt; x="home = /home/roberto, user = roberto"
      
      x = string.gsub("4+5 = $return 4+5$", "%$(.-)%$", function (s)
-           return loadstring(s)()
+           return load(s)()
          end)
      --&gt; x="4+5 = 9"
      
-     local t = {name="lua", version="5.1"}
+     local t = {name="lua", version="5.2"}
      x = string.gsub("$name-$version.tar.gz", "%$(%w+)", t)
-     --&gt; x="lua-5.1.tar.gz"
+     --&gt; x="lua-5.2.tar.gz"
 </pre>
 
 
@@ -6894,9 +7854,11 @@ its default value is&nbsp;1 and can be negative.
 
 
 <p>
-<hr><h3><a name="pdf-string.rep"><code>string.rep (s, n)</code></a></h3>
+<hr><h3><a name="pdf-string.rep"><code>string.rep (s, n [, sep])</code></a></h3>
 Returns a string that is the concatenation of <code>n</code> copies of
-the string <code>s</code>.
+the string <code>s</code> separated by the string <code>sep</code>.
+The default value for <code>sep</code> is the empty string
+(that is, no separator).
 
 
 
@@ -6933,7 +7895,7 @@ 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>
+<h3>6.4.1 &ndash; <a name="6.4.1">Patterns</a></h3>
 
 
 <h4>Character Class:</h4><p>
@@ -6942,35 +7904,35 @@ The following combinations are allowed in describing a character class:
 
 <ul>
 
-<li><b><em>x</em>:</b>
+<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>.</code>: </b> (a dot) represents all characters.</li>
 
-<li><b><code>%a</code>:</b> represents all letters.</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>%c</code>: </b> represents all control characters.</li>
 
-<li><b><code>%d</code>:</b> represents all digits.</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>%g</code>: </b> represents all printable characters except space.</li>
 
-<li><b><code>%p</code>:</b> represents all punctuation characters.</li>
+<li><b><code>%l</code>: </b> represents all lowercase letters.</li>
 
-<li><b><code>%s</code>:</b> represents all space characters.</li>
+<li><b><code>%p</code>: </b> represents all punctuation characters.</li>
 
-<li><b><code>%u</code>:</b> represents all uppercase letters.</li>
+<li><b><code>%s</code>: </b> represents all space characters.</li>
 
-<li><b><code>%w</code>:</b> represents all alphanumeric characters.</li>
+<li><b><code>%u</code>: </b> represents all uppercase letters.</li>
 
-<li><b><code>%x</code>:</b> represents all hexadecimal digits.</li>
+<li><b><code>%w</code>: </b> represents all alphanumeric characters.</li>
 
-<li><b><code>%z</code>:</b> represents the character with representation 0.</li>
+<li><b><code>%x</code>: </b> represents all hexadecimal digits.</li>
 
-<li><b><code>%<em>x</em></code>:</b> (where <em>x</em> is any non-alphanumeric character)
+<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)
@@ -6978,11 +7940,12 @@ can be preceded by a '<code>%</code>'
 when used to represent itself in a pattern.
 </li>
 
-<li><b><code>[<em>set</em>]</code>:</b>
+<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>'.
+separating the end characters of the range,
+in ascending order, 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.
@@ -6999,7 +7962,7 @@ Therefore, patterns like <code>[%a-z]</code> or <code>[a-%%]</code>
 have no meaning.
 </li>
 
-<li><b><code>[^<em>set</em>]</code>:</b>
+<li><b><code>[^<em>set</em>]</code>: </b>
 represents the complement of <em>set</em>,
 where <em>set</em> is interpreted as above.
 </li>
@@ -7045,7 +8008,7 @@ These repetition items will always match the longest possible sequence;
 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;
+these repetition items will always match the shortest possible sequence;
 </li>
 
 <li>
@@ -7070,6 +8033,16 @@ For instance, the item <code>%b()</code> matches expressions with
 balanced parentheses.
 </li>
 
+<li>
+<code>%f[<em>set</em>]</code>, a <em>frontier pattern</em>;
+such item matches an empty string at any position such that
+the next character belongs to <em>set</em>
+and the previous character does not belong to <em>set</em>.
+The set <em>set</em> is interpreted as previously described.
+The beginning and the end of the subject are handled as if
+they were the character '<code>\0</code>'.
+</li>
+
 </ul>
 
 
@@ -7108,8 +8081,6 @@ For instance, if we apply the pattern <code>"()aa()"</code> on the
 string <code>"flaaap"</code>, there will be two captures: 3&nbsp;and&nbsp;5.
 
 
-<p>
-A pattern cannot contain embedded zeros.  Use <code>%z</code> instead.
 
 
 
@@ -7119,86 +8090,98 @@ A pattern cannot contain embedded zeros.  Use <code>%z</code> instead.
 
 
 
+<h2>6.5 &ndash; <a name="6.5">Table Manipulation</a></h2>
 
-
-<h2>5.5 - <a name="5.5">Table Manipulation</a></h2><p>
+<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.
+Remember that, whenever an operation needs the length of a table,
+the table should be a proper sequence
+or have a <code>__len</code> metamethod (see <a href="#3.4.6">&sect;3.4.6</a>).
+All functions ignore non-numeric keys
+in tables given as arguments.
+
+
+<p>
+For performance reasons,
+all table accesses (get/set) performed by these functions are raw.
 
 
 <p>
-<hr><h3><a name="pdf-table.concat"><code>table.concat (table [, sep [, i [, j]]])</code></a></h3>
-Given an array where all elements are strings or numbers,
-returns <code>table[i]..sep..table[i+1] &middot;&middot;&middot; sep..table[j]</code>.
+<hr><h3><a name="pdf-table.concat"><code>table.concat (list [, sep [, i [, j]]])</code></a></h3>
+
+
+<p>
+Given a list where all elements are strings or numbers,
+returns <code>list[i]..sep..list[i+1] &middot;&middot;&middot; sep..list[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.
+and the default for <code>j</code> is <code>#list</code>.
 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>
+<hr><h3><a name="pdf-table.insert"><code>table.insert (list, [pos,] value)</code></a></h3>
 
 
 <p>
-Inserts element <code>value</code> at position <code>pos</code> in <code>table</code>,
-shifting up other elements to open space, if necessary.
-The default value for <code>pos</code> is <code>n+1</code>,
-where <code>n</code> is the length of the table (see <a href="#2.5.5">&sect;2.5.5</a>),
+Inserts element <code>value</code> at position <code>pos</code> in <code>list</code>,
+shifting up the elements
+<code>list[pos], list[pos+1], &middot;&middot;&middot;, list[#list]</code>.
+The default value for <code>pos</code> is <code>#list+1</code>,
 so that a call <code>table.insert(t,x)</code> inserts <code>x</code> at the end
-of table <code>t</code>.
+of list <code>t</code>.
 
 
 
 
 <p>
-<hr><h3><a name="pdf-table.maxn"><code>table.maxn (table)</code></a></h3>
+<hr><h3><a name="pdf-table.pack"><code>table.pack (&middot;&middot;&middot;)</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.) 
+Returns a new table with all parameters stored into keys 1, 2, etc.
+and with a field "<code>n</code>" with the total number of parameters.
+Also returns, as a second result, the total number of parameters.
+Note that the resulting table may not be a sequence.
 
 
 
 
 <p>
-<hr><h3><a name="pdf-table.remove"><code>table.remove (table [, pos])</code></a></h3>
+<hr><h3><a name="pdf-table.remove"><code>table.remove (list [, 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.
+Removes from <code>list</code> the element at position <code>pos</code>,
+shifting down the elements
+<code>list[pos+1], list[pos+2], &middot;&middot;&middot;, list[#list]</code>
+and erasing element <code>list[#list]</code>.
 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,
+The default value for <code>pos</code> is <code>#list</code>,
 so that a call <code>table.remove(t)</code> removes the last element
-of table <code>t</code>.
+of list <code>t</code>.
+
+
 
 
+<p>
+<hr><h3><a name="pdf-table.sort"><code>table.sort (list [, comp])</code></a></h3>
 
 
 <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.
+Sorts list elements in a given order, <em>in-place</em>,
+from <code>list[1]</code> to <code>list[#list]</code>.
 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).
+then it must be a function that receives two list elements
+and returns true when the first element must come
+before the second in the final order
+(so that <code>not comp(list[i+1],list[i])</code> will be true after the sort).
 If <code>comp</code> is not given,
 then the standard Lua operator <code>&lt;</code> is used instead.
 
@@ -7211,10 +8194,26 @@ may have their relative positions changed by the sort.
 
 
 
+<p>
+<hr><h3><a name="pdf-table.unpack"><code>table.unpack (list [, i [, j]])</code></a></h3>
+
+
+<p>
+Returns the elements from the given table.
+This function is equivalent to
+
+<pre>
+     return list[i], list[i+1], &middot;&middot;&middot;, list[j]
+</pre><p>
+By default, <code>i</code> is&nbsp;1 and <code>j</code> is <code>#list</code>.
+
+
+
 
 
 
-<h2>5.6 - <a name="5.6">Mathematical Functions</a></h2>
+
+<h2>6.6 &ndash; <a name="6.6">Mathematical Functions</a></h2>
 
 <p>
 This library is an interface to the standard C&nbsp;math library.
@@ -7380,21 +8379,13 @@ 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>
+<hr><h3><a name="pdf-math.log"><code>math.log (x [, base])</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>.
+Returns the logarithm of <code>x</code> in the given base.
+The default for <code>base</code> is <em>e</em>
+(so that the function returns the natural logarithm of <code>x</code>).
 
 
 
@@ -7435,7 +8426,7 @@ the integral part of <code>x</code> and the fractional part of <code>x</code>.
 
 
 <p>
-The value of <em>pi</em>.
+The value of <em>&pi;</em>.
 
 
 
@@ -7467,7 +8458,7 @@ Returns the angle <code>x</code> (given in degrees) in radians.
 
 <p>
 This function is an interface to the simple
-pseudo-random generator function <code>rand</code> provided by ANSI&nbsp;C.
+pseudo-random generator function <code>rand</code> provided by Standard&nbsp;C.
 (No guarantees can be given for its statistical properties.)
 
 
@@ -7551,7 +8542,234 @@ Returns the hyperbolic tangent of <code>x</code>.
 
 
 
-<h2>5.7 - <a name="5.7">Input and Output Facilities</a></h2>
+<h2>6.7 &ndash; <a name="6.7">Bitwise Operations</a></h2>
+
+<p>
+This library provides bitwise operations.
+It provides all its functions inside the table <a name="pdf-bit32"><code>bit32</code></a>.
+
+
+<p>
+Unless otherwise stated,
+all functions accept numeric arguments in the range
+<em>(-2<sup>51</sup>,+2<sup>51</sup>)</em>;
+each argument is normalized to
+the remainder of its division by <em>2<sup>32</sup></em>
+and truncated to an integer (in some unspecified way),
+so that its final value falls in the range <em>[0,2<sup>32</sup> - 1]</em>.
+Similarly, all results are in the range <em>[0,2<sup>32</sup> - 1]</em>.
+Note that <code>bit32.bnot(0)</code> is <code>0xFFFFFFFF</code>,
+which is different from <code>-1</code>.
+
+
+<p>
+<hr><h3><a name="pdf-bit32.arshift"><code>bit32.arshift (x, disp)</code></a></h3>
+
+
+<p>
+Returns the number <code>x</code> shifted <code>disp</code> bits to the right.
+The number <code>disp</code> may be any representable integer.
+Negative displacements shift to the left.
+
+
+<p>
+This shift operation is what is called arithmetic shift.
+Vacant bits on the left are filled
+with copies of the higher bit of <code>x</code>;
+vacant bits on the right are filled with zeros.
+In particular,
+displacements with absolute values higher than 31
+result in zero or <code>0xFFFFFFFF</code> (all original bits are shifted out).
+
+
+
+
+<p>
+<hr><h3><a name="pdf-bit32.band"><code>bit32.band (&middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Returns the bitwise and of its operands.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-bit32.bnot"><code>bit32.bnot (x)</code></a></h3>
+
+
+<p>
+Returns the bitwise negation of <code>x</code>.
+For any integer <code>x</code>,
+the following identity holds:
+
+<pre>
+     assert(bit32.bnot(x) == (-1 - x) % 2^32)
+</pre>
+
+
+
+<p>
+<hr><h3><a name="pdf-bit32.bor"><code>bit32.bor (&middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Returns the bitwise or of its operands.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-bit32.btest"><code>bit32.btest (&middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Returns a boolean signaling
+whether the bitwise and of its operands is different from zero.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-bit32.bxor"><code>bit32.bxor (&middot;&middot;&middot;)</code></a></h3>
+
+
+<p>
+Returns the bitwise exclusive or of its operands.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-bit32.extract"><code>bit32.extract (n, field [, width])</code></a></h3>
+
+
+<p>
+Returns the unsigned number formed by the bits
+<code>field</code> to <code>field + width - 1</code> from <code>n</code>.
+Bits are numbered from 0 (least significant) to 31 (most significant).
+All accessed bits must be in the range <em>[0, 31]</em>.
+
+
+<p>
+The default for <code>width</code> is 1.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-bit32.replace"><code>bit32.replace (n, v, field [, width])</code></a></h3>
+
+
+<p>
+Returns a copy of <code>n</code> with
+the bits <code>field</code> to <code>field + width - 1</code>
+replaced by the value <code>v</code>.
+See <a href="#pdf-bit32.extract"><code>bit32.extract</code></a> for details about <code>field</code> and <code>width</code>.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-bit32.lrotate"><code>bit32.lrotate (x, disp)</code></a></h3>
+
+
+<p>
+Returns the number <code>x</code> rotated <code>disp</code> bits to the left.
+The number <code>disp</code> may be any representable integer.
+
+
+<p>
+For any valid displacement,
+the following identity holds:
+
+<pre>
+     assert(bit32.lrotate(x, disp) == bit32.lrotate(x, disp % 32))
+</pre><p>
+In particular,
+negative displacements rotate to the right.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-bit32.lshift"><code>bit32.lshift (x, disp)</code></a></h3>
+
+
+<p>
+Returns the number <code>x</code> shifted <code>disp</code> bits to the left.
+The number <code>disp</code> may be any representable integer.
+Negative displacements shift to the right.
+In any direction, vacant bits are filled with zeros.
+In particular,
+displacements with absolute values higher than 31
+result in zero (all bits are shifted out).
+
+
+<p>
+For positive displacements,
+the following equality holds:
+
+<pre>
+     assert(bit32.lshift(b, disp) == (b * 2^disp) % 2^32)
+</pre>
+
+
+
+<p>
+<hr><h3><a name="pdf-bit32.rrotate"><code>bit32.rrotate (x, disp)</code></a></h3>
+
+
+<p>
+Returns the number <code>x</code> rotated <code>disp</code> bits to the right.
+The number <code>disp</code> may be any representable integer.
+
+
+<p>
+For any valid displacement,
+the following identity holds:
+
+<pre>
+     assert(bit32.rrotate(x, disp) == bit32.rrotate(x, disp % 32))
+</pre><p>
+In particular,
+negative displacements rotate to the left.
+
+
+
+
+<p>
+<hr><h3><a name="pdf-bit32.rshift"><code>bit32.rshift (x, disp)</code></a></h3>
+
+
+<p>
+Returns the number <code>x</code> shifted <code>disp</code> bits to the right.
+The number <code>disp</code> may be any representable integer.
+Negative displacements shift to the left.
+In any direction, vacant bits are filled with zeros.
+In particular,
+displacements with absolute values higher than 31
+result in zero (all bits are shifted out).
+
+
+<p>
+For positive displacements,
+the following equality holds:
+
+<pre>
+     assert(bit32.rshift(b, disp) == math.floor(b % 2^32 / 2^disp))
+</pre>
+
+<p>
+This shift operation is what is called logical shift.
+
+
+
+
+
+
+
+<h2>6.8 &ndash; <a name="6.8">Input and Output Facilities</a></h2>
 
 <p>
 The I/O library provides two different styles for file manipulation.
@@ -7601,7 +8819,7 @@ Without a <code>file</code>, closes the default output file.
 
 
 <p>
-Equivalent to <code>file:flush</code> over the default output file.
+Equivalent to <code>io.output():flush()</code>.
 
 
 
@@ -7627,20 +8845,13 @@ instead of returning an error code.
 
 
 <p>
-<hr><h3><a name="pdf-io.lines"><code>io.lines ([filename])</code></a></h3>
+<hr><h3><a name="pdf-io.lines"><code>io.lines ([filename] &middot;&middot;&middot;)</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.
+and returns an iterator function that
+works like <code>file:lines(&middot;&middot;&middot;)</code> over the opened file.
 When the iterator function detects the end of file,
 it returns <b>nil</b> (to finish the loop) and automatically closes the file.
 
@@ -7669,18 +8880,16 @@ or, in case of errors, <b>nil</b> plus an error message.
 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,
+<li><b>"<code>r</code>": </b> read mode (the default);</li>
+<li><b>"<code>w</code>": </b> write mode;</li>
+<li><b>"<code>a</code>": </b> append mode;</li>
+<li><b>"<code>r+</code>": </b> update mode, all previous data is preserved;</li>
+<li><b>"<code>w+</code>": </b> update mode, all previous data is erased;</li>
+<li><b>"<code>a+</code>": </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&nbsp;C function <code>fopen</code>.
 
 
 
@@ -7700,6 +8909,11 @@ Similar to <a href="#pdf-io.input"><code>io.input</code></a>, but operates over
 
 
 <p>
+This function is system dependent and is not available
+on all platforms.
+
+
+<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)
@@ -7707,11 +8921,6 @@ 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>
@@ -7719,7 +8928,7 @@ on all platforms.
 
 
 <p>
-Equivalent to <code>io.input():read</code>.
+Equivalent to <code>io.input():read(&middot;&middot;&middot;)</code>.
 
 
 
@@ -7754,7 +8963,7 @@ or <b>nil</b> if <code>obj</code> is not a file handle.
 
 
 <p>
-Equivalent to <code>io.output():write</code>.
+Equivalent to <code>io.output():write(&middot;&middot;&middot;)</code>.
 
 
 
@@ -7770,6 +8979,12 @@ their handles are garbage collected,
 but that takes an unpredictable amount of time to happen.
 
 
+<p>
+When closing a file handle created with <a href="#pdf-io.popen"><code>io.popen</code></a>,
+<a href="#pdf-file:close"><code>file:close</code></a> returns the same values
+returned by <a href="#pdf-os.execute"><code>os.execute</code></a>.
+
+
 
 
 <p>
@@ -7783,19 +8998,22 @@ Saves any written data to <code>file</code>.
 
 
 <p>
-<hr><h3><a name="pdf-file:lines"><code>file:lines ()</code></a></h3>
+<hr><h3><a name="pdf-file:lines"><code>file:lines (&middot;&middot;&middot;)</code></a></h3>
 
 
 <p>
 Returns an iterator function that,
 each time it is called,
-returns a new line from the file.
+reads the file according to the given formats.
+When no format is given,
+uses "*l" as a default.
 Therefore, the construction
 
 <pre>
-     for line in file:lines() do <em>body</em> end
+     for c in file:lines(1) do <em>body</em> end
 </pre><p>
-will iterate over all lines of the file.
+will iterate over all characters of the file,
+starting at the current position.
 (Unlike <a href="#pdf-io.lines"><code>io.lines</code></a>, this function does not close the file
 when the loop ends.)
 
@@ -7813,7 +9031,7 @@ 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
+it uses a default format that reads the next line
 (see below).
 
 
@@ -7822,23 +9040,28 @@ The available formats are
 
 <ul>
 
-<li><b>"*n":</b>
+<li><b>"<code>*n</code>": </b>
 reads a number;
 this is the only format that returns a number instead of a string.
 </li>
 
-<li><b>"*a":</b>
+<li><b>"<code>*a</code>": </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),
+<li><b>"<code>*l</code>": </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>
+<li><b>"<code>*L</code>": </b>
+reads the next line keeping the end of line (if present),
+returning <b>nil</b> on end of file.
+</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,
@@ -7861,9 +9084,9 @@ 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>
+<li><b>"<code>set</code>": </b> base is position 0 (beginning of the file);</li>
+<li><b>"<code>cur</code>": </b> base is current position;</li>
+<li><b>"<code>end</code>": </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.
@@ -7894,17 +9117,17 @@ There are three available modes:
 
 <ul>
 
-<li><b>"no":</b>
+<li><b>"<code>no</code>": </b>
 no buffering; the result of any output operation appears immediately.
 </li>
 
-<li><b>"full":</b>
+<li><b>"<code>full</code>": </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>
+<li><b>"<code>line</code>": </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).
@@ -7930,12 +9153,17 @@ 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>.
 
 
+<p>
+In case of success, this function returns <code>file</code>.
+Otherwise it returns <b>nil</b> plus a string describing the error.
+
+
 
 
 
 
 
-<h2>5.8 - <a name="5.8">Operating System Facilities</a></h2>
+<h2>6.9 &ndash; <a name="6.9">Operating System Facilities</a></h2>
 
 <p>
 This library is implemented through table <a name="pdf-os"><code>os</code></a>.
@@ -7979,6 +9207,8 @@ then <code>date</code> returns a table with the following fields:
 <code>wday</code> (weekday, Sunday is&nbsp;1),
 <code>yday</code> (day of the year),
 and <code>isdst</code> (daylight saving flag, a boolean).
+This last field may be absent
+if the information is not available.
 
 
 <p>
@@ -8015,22 +9245,52 @@ this value is exactly <code>t2</code><em>-</em><code>t1</code>.
 <p>
 This function is equivalent to the C&nbsp;function <code>system</code>.
 It passes <code>command</code> to be executed by an operating system shell.
-It returns a status code, which is system-dependent.
-If <code>command</code> is absent, then it returns nonzero if a shell is available
-and zero otherwise.
+Its first result is <b>true</b>
+if the command terminated successfully,
+or <b>nil</b> otherwise.
+After this first result
+the function returns a string and a number,
+as follows:
+
+<ul>
 
+<li><b>"<code>exit</code>": </b>
+the command terminated normally;
+the following number is the exit status of the command.
+</li>
 
+<li><b>"<code>signal</code>": </b>
+the command was terminated by a signal;
+the following number is the signal that terminated the command.
+</li>
 
+</ul>
 
 <p>
-<hr><h3><a name="pdf-os.exit"><code>os.exit ([code])</code></a></h3>
+When called without a <code>command</code>,
+<code>os.execute</code> returns a boolean that is true if a shell is available.
+
+
 
 
 <p>
-Calls the C&nbsp;function <code>exit</code>,
-with an optional <code>code</code>,
-to terminate the host program.
-The default value for <code>code</code> is the success code.
+<hr><h3><a name="pdf-os.exit"><code>os.exit ([code [, close])</code></a></h3>
+
+
+<p>
+Calls the C&nbsp;function <code>exit</code> to terminate the host program.
+If <code>code</code> is <b>true</b>,
+the returned status is <code>EXIT_SUCCESS</code>;
+if <code>code</code> is <b>false</b>,
+the returned status is <code>EXIT_FAILURE</code>;
+if <code>code</code> is a number,
+the returned status is this number.
+The default value for <code>code</code> is <b>true</b>.
+
+
+<p>
+If the optional second argument <code>close</code> is true,
+closes the Lua state before exiting.
 
 
 
@@ -8051,8 +9311,8 @@ or <b>nil</b> if the variable is not defined.
 
 
 <p>
-Deletes the file or directory with the given name.
-Directories must be empty to be removed.
+Deletes the file (or empty directory, on POSIX systems)
+with the given name.
 If this function fails, it returns <b>nil</b>,
 plus a string describing the error.
 
@@ -8115,7 +9375,8 @@ and may have fields <code>hour</code>, <code>min</code>, <code>sec</code>, and <
 
 <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
+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
@@ -8136,7 +9397,7 @@ and explicitly removed when no longer needed.
 
 
 <p>
-On some systems (POSIX),
+On POSIX systems,
 this function also creates a file with that name,
 to avoid security risks.
 (Someone else might create the file with wrong permissions
@@ -8156,23 +9417,20 @@ which automatically removes the file when the program ends.
 
 
 
-<h2>5.9 - <a name="5.9">The Debug Library</a></h2>
+<h2>6.10 &ndash; <a name="6.10">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
+Several of these functions
+violate basic 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)
+cannot be accessed from outside;
+that userdata metatables cannot be changed by Lua code;
+that Lua programs do not crash)
 and therefore can compromise otherwise secure code.
+Moreover, some functions in this library may be slow.
 
 
 <p>
@@ -8206,13 +9464,6 @@ 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>
 
 
@@ -8236,7 +9487,8 @@ or you can give a number as the value of <code>function</code>,
 which means the function running at level <code>function</code> of the call stack
 of the given thread:
 level&nbsp;0 is the current function (<code>getinfo</code> itself);
-level&nbsp;1 is the function that called <code>getinfo</code>;
+level&nbsp;1 is the function that called <code>getinfo</code>
+(except for tail calls, which do not count on the stack);
 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>.
@@ -8268,24 +9520,35 @@ 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>
+<hr><h3><a name="pdf-debug.getlocal"><code>debug.getlocal ([thread,] f, local)</code></a></h3>
 
 
 <p>
 This function returns the name and the value of the local variable
-with index <code>local</code> of the function at level <code>level</code> of the stack.
-(The first parameter or local variable has index&nbsp;1, and so on,
-until the last active local variable.)
-The function returns <b>nil</b> if there is no local
-variable with the given index,
-and raises an error when called with a <code>level</code> out of range.
+with index <code>local</code> of the function at level <code>f</code> of the stack.
+This function accesses not only explicit local variables,
+but also parameters, temporaries, etc.
+
+
+<p>
+The first parameter or local variable has index&nbsp;1, and so on,
+until the last active variable.
+Negative indices refer to vararg parameters;
+-1 is the first vararg parameter.
+The function returns <b>nil</b> if there is no variable with the given index,
+and raises an error when called with a level out of range.
 (You can call <a href="#pdf-debug.getinfo"><code>debug.getinfo</code></a> to check whether the level is valid.)
 
 
 <p>
 Variable names starting with '<code>(</code>' (open parentheses)
 represent internal variables
-(loop control variables, temporaries, and C&nbsp;function locals).
+(loop control variables, temporaries, varargs, and C&nbsp;function locals).
+
+
+<p>
+The parameter <code>f</code> may also be a function.
+In that case, <code>getlocal</code> returns only the name of function parameters.
 
 
 
@@ -8306,7 +9569,7 @@ or <b>nil</b> if it does not have a metatable.
 
 
 <p>
-Returns the registry table (see <a href="#3.5">&sect;3.5</a>).
+Returns the registry table (see <a href="#4.5">&sect;4.5</a>).
 
 
 
@@ -8324,12 +9587,13 @@ 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>
+<hr><h3><a name="pdf-debug.getuservalue"><code>debug.getuservalue (u)</code></a></h3>
 
 
 <p>
-Sets the environment of the given <code>object</code> to the given <code>table</code>.
-Returns <code>object</code>.
+Returns the Lua value associated to <code>u</code>.
+If <code>u</code> is not a userdata,
+returns <b>nil</b>.
 
 
 
@@ -8346,9 +9610,9 @@ 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>
+<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.
@@ -8362,8 +9626,8 @@ When called without arguments,
 <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>"call"</code> (or <code>"tail call"</code>),
+<code>"return"</code>,
 <code>"line"</code>, and <code>"count"</code>.
 For line events,
 the hook also gets the new line number as its second parameter.
@@ -8371,10 +9635,7 @@ Inside a hook,
 you can call <code>getinfo</code> with level&nbsp;2 to get more information about
 the running function
 (level&nbsp;0 is the <code>getinfo</code> function,
-and level&nbsp;1 is the hook function),
-unless the event is <code>"tail return"</code>.
-In this case, Lua is only simulating the return,
-and a call to <code>getinfo</code> will return invalid data.
+and level&nbsp;1 is the hook function).
 
 
 
@@ -8393,6 +9654,11 @@ and raises an error when called with a <code>level</code> out of range.
 Otherwise, it returns the name of the local variable.
 
 
+<p>
+See <a href="#pdf-debug.getlocal"><code>debug.getlocal</code></a> for more information about
+variable indices and names.
+
+
 
 
 <p>
@@ -8402,6 +9668,7 @@ Otherwise, it returns the name of the local variable.
 <p>
 Sets the metatable for the given <code>object</code> to the given <code>table</code>
 (which can be <b>nil</b>).
+Returns <code>object</code>.
 
 
 
@@ -8421,11 +9688,31 @@ 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>
+<hr><h3><a name="pdf-debug.setuservalue"><code>debug.setuservalue (udata, value)</code></a></h3>
+
+
+<p>
+Sets the given <code>value</code> as
+the Lua value associated to the given <code>udata</code>.
+<code>value</code> must be a table or <b>nil</b>;
+<code>udata</code> must be a full userdata.
+
+
+<p>
+Returns <code>udata</code>.
+
+
 
 
 <p>
-Returns a string with a traceback of the call stack.
+<hr><h3><a name="pdf-debug.traceback"><code>debug.traceback ([thread,] [message [, level]])</code></a></h3>
+
+
+<p>
+If <code>message</code> is present but is neither a string nor <b>nil</b>,
+this function returns <code>message</code> without further processing.
+Otherwise,
+it 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
@@ -8435,19 +9722,50 @@ to start the traceback
 
 
 
+<p>
+<hr><h3><a name="pdf-debug.upvalueid"><code>debug.upvalueid (function, n)</code></a></h3>
+
+
+<p>
+Returns an unique identifier (as a light userdata)
+for the upvalue numbered <code>n</code>
+from the given function.
+
+
+<p>
+These unique identifiers allow a program to check whether different
+closures share upvalues.
+Lua closures that share an upvalue
+(that is, that access a same external local variable)
+will return identical ids for those upvalue indices.
 
 
 
-<h1>6 - <a name="6">Lua Stand-alone</a></h1>
+
+<p>
+<hr><h3><a name="pdf-debug.upvaluejoin"><code>debug.upvaluejoin (func1, n1, func2, n2)</code></a></h3>
+
+
+<p>
+Make the <code>n1</code>-th upvalue of the Lua closure <code>func1</code>
+refer to the <code>n2</code>-th upvalue of the Lua closure <code>func2</code>.
+
+
+
+
+
+
+
+<h1>7 &ndash; <a name="7">Lua Standalone</a></h1>
 
 <p>
 Although Lua has been designed as an extension language,
 to be embedded in a host C&nbsp;program,
-it is also frequently used as a stand-alone language.
-An interpreter for Lua as a stand-alone language,
+it is also frequently used as a standalone language.
+An interpreter for Lua as a standalone language,
 called simply <code>lua</code>,
 is provided with the standard distribution.
-The stand-alone interpreter includes
+The standalone interpreter includes
 all standard libraries, including the debug library.
 Its usage is:
 
@@ -8457,12 +9775,12 @@ Its usage is:
 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>
+<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.
@@ -8474,7 +9792,8 @@ 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>.
+the interpreter checks for an environment variable <a name="pdf-LUA_INIT_5_2"><code>LUA_INIT_5_2</code></a>
+(or <a name="pdf-LUA_INIT"><code>LUA_INIT</code></a> if it is not defined).
 If its format is <code>@<em>filename</em></code>,
 then <code>lua</code> executes the file.
 Otherwise, <code>lua</code> executes the string itself.
@@ -8489,7 +9808,7 @@ For instance, an invocation like
 </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>$</code> is the shell prompt. Your prompt may be different.)
+(Here <code>$</code> is the shell prompt. Your prompt can be different.)
 
 
 <p>
@@ -8529,6 +9848,25 @@ by issuing a different prompt.
 
 
 <p>
+In case of unprotected errors in the script,
+the interpreter reports the error to the standard error stream.
+If the error object is a string,
+the interpreter adds a stack traceback to it.
+Otherwise, if the error object has a metamethod <code>__tostring</code>,
+the interpreter calls this metamethod to produce the final message.
+Finally, if the error object is <b>nil</b>,
+the interpreter does not report the error.
+
+
+<p>
+When finishing normally,
+the interpreter closes its main Lua state
+(see <a href="#lua_close"><code>lua_close</code></a>).
+The script can avoid this step by terminating
+through <a href="#pdf-os.exit"><code>os.exit</code></a>.
+
+
+<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,
@@ -8552,7 +9890,7 @@ 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 standalone interpreter skips
 the first line of a chunk if it starts with <code>#</code>.
 Therefore, Lua scripts can be made into executable programs
 by using <code>chmod +x</code> and the&nbsp;<code>#!</code> form,
@@ -8562,48 +9900,79 @@ as in
      #!/usr/local/bin/lua
 </pre><p>
 (Of course,
-the location of the Lua interpreter may be different in your machine.
+the location of the Lua interpreter can be different in your machine.
 If <code>lua</code> is in your <code>PATH</code>,
-then 
+then
 
 <pre>
      #!/usr/bin/env lua
 </pre><p>
-is a more portable solution.) 
+is a more portable solution.)
 
 
 
-<h1>7 - <a name="7">Incompatibilities with the Previous Version</a></h1>
+<h1>8 &ndash; <a name="8">Incompatibilities with the Previous Version</a></h1>
 
 <p>
-Here we list the incompatibilities that you may find when moving a program
-from Lua&nbsp;5.0 to Lua&nbsp;5.1.
-You can avoid most of the incompatibilities compiling Lua with
+Here we list the incompatibilities that you can find when moving a program
+from Lua&nbsp;5.1 to Lua&nbsp;5.2.
+You can avoid some 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>
+<h2>8.1 &ndash; <a name="8.1">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>.)
+The concept of <em>environment</em> changed.
+Only Lua functions have environments.
+To set the environment of a Lua function,
+use the variable <code>_ENV</code> or the function <a href="#pdf-load"><code>load</code></a>.
+
+
+<p>
+C functions do not have environments any more.
+Use an upvalue with a shared table if you need to keep
+shared state among several C functions.
+(You may use <a href="#luaL_setfuncs"><code>luaL_setfuncs</code></a> to open a C library
+with all functions sharing a common upvalue.)
+
+
+<p>
+To manipulate the "environment" of a userdata
+(which is now called user value),
+use the new functions
+<a href="#lua_getuservalue"><code>lua_getuservalue</code></a> and <a href="#lua_setuservalue"><code>lua_setuservalue</code></a>.
+</li>
+
+<li>
+Lua identifiers cannot use locale-dependent letters.
+</li>
+
+<li>
+Doing a step or a full collection in the garbage collector
+does not restart the collector if it has been stopped.
+</li>
+
+<li>
+Weak tables with weak keys now perform like <em>ephemeron tables</em>.
 </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.
+The event <em>tail return</em> in debug hooks was removed.
+Instead, tail calls generate a special new event,
+<em>tail call</em>, so that the debugger can know there will
+not be a corresponding return event.
 </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>.)
+Equality between function values has changed.
+Now, a function definition may not create a new value;
+it may reuse some previous value if there is no
+observable difference to the new function.
 </li>
 
 </ul>
@@ -8611,57 +9980,66 @@ You can use the new syntax (<code>[=[<em>string</em>]=]</code>) in these cases.
 
 
 
-<h2>7.2 - <a name="7.2">Changes in the Libraries</a></h2>
+<h2>8.2 &ndash; <a name="8.2">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>.)
+Function <code>module</code> is deprecated.
+Modules are not expected to set global variables anymore,
+and it is easy to set up a module with regular Lua code.
+</li>
+
+<li>
+Functions <code>setfenv</code> and <code>getfenv</code> were removed,
+because of the changes in environments.
 </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.
+Function <code>math.log10</code> is deprecated.
+Use <a href="#pdf-math.log"><code>math.log</code></a> with 10 as its second argument, instead.
 </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>.)
+Function <code>loadstring</code> is deprecated.
+Use <code>load</code> instead; it now accepts string arguments
+and are exactly equivalent to <code>loadstring</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>.)
+Function <code>table.maxn</code> is deprecated.
+Write it in Lua if you really need it.
 </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>.)
+Function <code>os.execute</code> now returns <b>true</b> when command
+terminates successfully and <b>nil</b> plus error information
+otherwise.
 </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.
+Function <code>unpack</code> was moved into the table library
+and therefore must be called as <a href="#pdf-table.unpack"><code>table.unpack</code></a>.
 </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>.
+Character class <code>%z</code> in patterns is deprecated,
+as now patterns may contain '<code>\0</code>' as a regular character.
 </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.
+The table <code>package.loaders</code> was renamed <code>package.searchers</code>.
+</li>
+
+<li>
+Lua does not have bytecode verification anymore.
+So, all functions that load code
+(<a href="#pdf-load"><code>load</code></a> and <a href="#pdf-loadfile"><code>loadfile</code></a>)
+are potentially insecure when loading untrusted binary data.
+(Actually, those functions were already insecure because
+of bugs in the verification algorithm.)
+When in doubt,
+use the <code>mode</code> argument in function <a href="#pdf-load"><code>load</code></a>
+to restrict it to loading textual chunks.
 </li>
 
 </ul>
@@ -8669,40 +10047,67 @@ use <code>collectgarbage("count")</code> instead.
 
 
 
-<h2>7.3 - <a name="7.3">Changes in the API</a></h2>
+<h2>8.3 &ndash; <a name="8.3">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.
+Pseudoindex <code>LUA_GLOBALSINDEX</code> was removed.
+You must get the global environment from the registry
+(see <a href="#4.5">&sect;4.5</a>).
+</li>
+
+<li>
+Pseudoindex <code>LUA_ENVIRONINDEX</code>
+and functions <code>lua_getfenv</code>/<code>lua_setfenv</code>
+were removed,
+as C&nbsp;functions do not have environments any more.
 </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>).
+Function <code>luaL_register</code> is deprecated.
+Use <a href="#luaL_setfuncs"><code>luaL_setfuncs</code></a> so that your module does not
+create globals anymore.
+(Modules are not expected to set global variables anymore.)
 </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>.
+The <code>osize</code> argument to the allocation function
+may not be zero when creating a new block,
+that is, when <code>ptr</code> is <code>NULL</code>
+(see <a href="#lua_Alloc"><code>lua_Alloc</code></a>).
+Use only the test <code>ptr == NULL</code> to check whether
+the block is new.
 </li>
 
 <li>
-Function <code>luaL_openlib</code> was replaced by <a href="#luaL_register"><code>luaL_register</code></a>.
+Finalizers (<code>__gc</code> metamethods) for userdata are called in the
+reverse order that they were marked,
+not that they were created (see <a href="#2.5.1">&sect;2.5.1</a>).
+(Most userdata are marked immediately after they are created.)
+Moreover,
+if the metatable does not have a <code>__gc</code> field when set,
+the finalizer will not be called,
+even if it is set later.
 </li>
 
 <li>
-Function <code>luaL_checkudata</code> now throws an error when the given value
-is not a userdata of the expected type.
-(In Lua&nbsp;5.0 it returned <code>NULL</code>.)
+<code>luaL_typerror</code> was removed.
+Write your own version if you need it.
+</li>
+
+<li>
+Function <code>lua_cpcall</code> is deprecated.
+You can simply push the function with <a href="#lua_pushcfunction"><code>lua_pushcfunction</code></a>
+and call it with <a href="#lua_pcall"><code>lua_pcall</code></a>.
+</li>
+
+<li>
+Functions <code>lua_equal</code> and <code>lua_lessthan</code> are deprecated.
+Use the new <a href="#lua_compare"><code>lua_compare</code></a> with appropriate options instead.
+</li>
+
+<li>
+Function <code>lua_objlen</code> was renamed <a href="#lua_rawlen"><code>lua_rawlen</code></a>.
 </li>
 
 </ul>
@@ -8710,7 +10115,7 @@ is not a userdata of the expected type.
 
 
 
-<h1>8 - <a name="8">The Complete Syntax of Lua</a></h1>
+<h1>9 &ndash; <a name="9">The Complete Syntax of Lua</a></h1>
 
 <p>
 Here is the complete syntax of Lua in extended BNF.
@@ -8721,62 +10126,68 @@ Here is the complete syntax of Lua in extended BNF.
 
 <pre>
 
-	chunk ::= {stat [`<b>;</b>&acute;]} [laststat [`<b>;</b>&acute;]]
+	chunk ::= block
 
-	block ::= chunk
+	block ::= {stat} [retstat]
 
-	stat ::=  varlist `<b>=</b>&acute; explist | 
+	stat ::=  &lsquo;<b>;</b>&rsquo; | 
+		 varlist &lsquo;<b>=</b>&rsquo; explist | 
 		 functioncall | 
+		 label | 
+		 <b>break</b> | 
+		 <b>goto</b> Name | 
 		 <b>do</b> block <b>end</b> | 
 		 <b>while</b> exp <b>do</b> block <b>end</b> | 
 		 <b>repeat</b> block <b>until</b> exp | 
 		 <b>if</b> exp <b>then</b> block {<b>elseif</b> exp <b>then</b> block} [<b>else</b> block] <b>end</b> | 
-		 <b>for</b> Name `<b>=</b>&acute; exp `<b>,</b>&acute; exp [`<b>,</b>&acute; exp] <b>do</b> block <b>end</b> | 
+		 <b>for</b> Name &lsquo;<b>=</b>&rsquo; exp &lsquo;<b>,</b>&rsquo; exp [&lsquo;<b>,</b>&rsquo; exp] <b>do</b> block <b>end</b> | 
 		 <b>for</b> namelist <b>in</b> explist <b>do</b> block <b>end</b> | 
 		 <b>function</b> funcname funcbody | 
 		 <b>local</b> <b>function</b> Name funcbody | 
-		 <b>local</b> namelist [`<b>=</b>&acute; explist] 
+		 <b>local</b> namelist [&lsquo;<b>=</b>&rsquo; explist] 
+
+	retstat ::= <b>return</b> [explist] [&lsquo;<b>;</b>&rsquo;]
 
-	laststat ::= <b>return</b> [explist] | <b>break</b>
+	label ::= &lsquo;<b>::</b>&rsquo; Name &lsquo;<b>::</b>&rsquo;
 
-	funcname ::= Name {`<b>.</b>&acute; Name} [`<b>:</b>&acute; Name]
+	funcname ::= Name {&lsquo;<b>.</b>&rsquo; Name} [&lsquo;<b>:</b>&rsquo; Name]
 
-	varlist ::= var {`<b>,</b>&acute; var}
+	varlist ::= var {&lsquo;<b>,</b>&rsquo; var}
 
-	var ::=  Name | prefixexp `<b>[</b>&acute; exp `<b>]</b>&acute; | prefixexp `<b>.</b>&acute; Name 
+	var ::=  Name | prefixexp &lsquo;<b>[</b>&rsquo; exp &lsquo;<b>]</b>&rsquo; | prefixexp &lsquo;<b>.</b>&rsquo; Name 
 
-	namelist ::= Name {`<b>,</b>&acute; Name}
+	namelist ::= Name {&lsquo;<b>,</b>&rsquo; Name}
 
-	explist ::= {exp `<b>,</b>&acute;} exp
+	explist ::= exp {&lsquo;<b>,</b>&rsquo; exp}
 
-	exp ::=  <b>nil</b> | <b>false</b> | <b>true</b> | Number | String | `<b>...</b>&acute; | function | 
+	exp ::=  <b>nil</b> | <b>false</b> | <b>true</b> | Number | String | &lsquo;<b>...</b>&rsquo; | function | 
 		 prefixexp | tableconstructor | exp binop exp | unop exp 
 
-	prefixexp ::= var | functioncall | `<b>(</b>&acute; exp `<b>)</b>&acute;
+	prefixexp ::= var | functioncall | &lsquo;<b>(</b>&rsquo; exp &lsquo;<b>)</b>&rsquo;
 
-	functioncall ::=  prefixexp args | prefixexp `<b>:</b>&acute; Name args 
+	functioncall ::=  prefixexp args | prefixexp &lsquo;<b>:</b>&rsquo; Name args 
 
-	args ::=  `<b>(</b>&acute; [explist] `<b>)</b>&acute; | tableconstructor | String 
+	args ::=  &lsquo;<b>(</b>&rsquo; [explist] &lsquo;<b>)</b>&rsquo; | tableconstructor | String 
 
-	function ::= <b>function</b> funcbody
+	functiondef ::= <b>function</b> funcbody
 
-	funcbody ::= `<b>(</b>&acute; [parlist] `<b>)</b>&acute; block <b>end</b>
+	funcbody ::= &lsquo;<b>(</b>&rsquo; [parlist] &lsquo;<b>)</b>&rsquo; block <b>end</b>
 
-	parlist ::= namelist [`<b>,</b>&acute; `<b>...</b>&acute;] | `<b>...</b>&acute;
+	parlist ::= namelist [&lsquo;<b>,</b>&rsquo; &lsquo;<b>...</b>&rsquo;] | &lsquo;<b>...</b>&rsquo;
 
-	tableconstructor ::= `<b>{</b>&acute; [fieldlist] `<b>}</b>&acute;
+	tableconstructor ::= &lsquo;<b>{</b>&rsquo; [fieldlist] &lsquo;<b>}</b>&rsquo;
 
 	fieldlist ::= field {fieldsep field} [fieldsep]
 
-	field ::= `<b>[</b>&acute; exp `<b>]</b>&acute; `<b>=</b>&acute; exp | Name `<b>=</b>&acute; exp | exp
+	field ::= &lsquo;<b>[</b>&rsquo; exp &lsquo;<b>]</b>&rsquo; &lsquo;<b>=</b>&rsquo; exp | Name &lsquo;<b>=</b>&rsquo; exp | exp
 
-	fieldsep ::= `<b>,</b>&acute; | `<b>;</b>&acute;
+	fieldsep ::= &lsquo;<b>,</b>&rsquo; | &lsquo;<b>;</b>&rsquo;
 
-	binop ::= `<b>+</b>&acute; | `<b>-</b>&acute; | `<b>*</b>&acute; | `<b>/</b>&acute; | `<b>^</b>&acute; | `<b>%</b>&acute; | `<b>..</b>&acute; | 
-		 `<b>&lt;</b>&acute; | `<b>&lt;=</b>&acute; | `<b>&gt;</b>&acute; | `<b>&gt;=</b>&acute; | `<b>==</b>&acute; | `<b>~=</b>&acute; | 
+	binop ::= &lsquo;<b>+</b>&rsquo; | &lsquo;<b>-</b>&rsquo; | &lsquo;<b>*</b>&rsquo; | &lsquo;<b>/</b>&rsquo; | &lsquo;<b>^</b>&rsquo; | &lsquo;<b>%</b>&rsquo; | &lsquo;<b>..</b>&rsquo; | 
+		 &lsquo;<b>&lt;</b>&rsquo; | &lsquo;<b>&lt;=</b>&rsquo; | &lsquo;<b>&gt;</b>&rsquo; | &lsquo;<b>&gt;=</b>&rsquo; | &lsquo;<b>==</b>&rsquo; | &lsquo;<b>~=</b>&rsquo; | 
 		 <b>and</b> | <b>or</b>
 
-	unop ::= `<b>-</b>&acute; | <b>not</b> | `<b>#</b>&acute;
+	unop ::= &lsquo;<b>-</b>&rsquo; | <b>not</b> | &lsquo;<b>#</b>&rsquo;
 
 </pre>
 
@@ -8789,12 +10200,12 @@ Here is the complete syntax of Lua in extended BNF.
 
 
 <HR>
-<SMALL>
+<SMALL CLASS="footer">
 Last update:
-Mon Aug 18 13:25:46 BRT 2008
+Fri Jul  8 17:11:02 BRT 2011
 </SMALL>
 <!--
-Last change: revised for Lua 5.1.4
+Last change: revised for Lua 5.2.0 (beta)
 -->
 
 </body></html>
diff --git a/doc/osi-certified-72x60.png b/doc/osi-certified-72x60.png
new file mode 100755
index 0000000..07df5f6
--- /dev/null
+++ b/doc/osi-certified-72x60.png
diff --git a/doc/readme.html b/doc/readme.html
index 38be6db..5cb41d4 100644..100755
--- a/doc/readme.html
+++ b/doc/readme.html
@@ -1,7 +1,25 @@
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
 <HTML>
 <HEAD>
-<TITLE>Lua documentation</TITLE>
+<TITLE>Lua 5.2 readme</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">
+blockquote, .display {
+	color: black ;
+	padding: 8px ;
+	border: solid #a0a0a0 2px ;
+	xbackground-color: #EFEFFF ;
+	margin-left: 0px ;
+}
+
+tt, kbd, code {
+	font-size: 120% ;
+	xcolor: black ;
+	xpadding: 4px ;
+	xbackground-color: #E0E0E0 ;
+}
+</STYLE>
 </HEAD>
 
 <BODY>
@@ -9,32 +27,381 @@
 <HR>
 <H1>
 <A HREF="http://www.lua.org/"><IMG SRC="logo.gif" ALT="Lua" BORDER=0></A>
-Documentation
+Welcome to Lua 5.2 (beta)
 </H1>
 
-This is the documentation included in the source distribution of Lua 5.1.4.
+<P>
+<IMG SRC="alert.png" ALIGN="absbottom" ALT="[!]">
+<EM>This is a beta version of Lua 5.2.
+Some details may change in the final version.</EM>
 
-<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>
+<P>
+<A HREF="#about">about</A>
+&middot;
+<A HREF="#install">installation</A>
+&middot;
+<A HREF="#changes">changes</A>
+&middot;
+<A HREF="#license">license</A>
+&middot;
+<A HREF="contents.html">reference manual</A>
+<HR>
 
+<H2><A NAME="about">About Lua</A></H2>
+
+<P>
+Lua is a powerful, fast, lightweight, embeddable scripting language
+developed by a
+<A HREF="http://www.lua.org/authors.html">team</A>
+at
+<A HREF="http://www.puc-rio.br/">PUC-Rio</A>,
+the Pontifical Catholic University of Rio de Janeiro in Brazil.
+Lua is
+<A HREF="#license">free software</A>
+used in many products and projects around the world.
+
+<P>
 Lua's
 <A HREF="http://www.lua.org/">official web site</A>
-contains updated documentation,
+provides complete information
+about Lua,
+including
+an
+<A HREF="http://www.lua.org/about.html">executive summary</A>
+and
+updated
+<A HREF="http://www.lua.org/docs.html">documentation</A>,
 especially the
-<A HREF="http://www.lua.org/manual/5.1/">reference manual</A>.
+<A HREF="http://www.lua.org/manual/5.2/">reference manual</A>,
+which may differ slightly from the
+<A HREF="contents.html">local copy</A>
+distributed in this package.
+
+<H2><A NAME="install">Installing Lua</A></H2>
+
+<P>
+Lua is distributed in
+<A HREF="http://www.lua.org/ftp/">source</A>
+form.
+You need to build it before using it.
+Building Lua should be straightforward
+because
+Lua is implemented in pure ANSI C, and compiles unmodified in all known
+platforms that have an ANSI C compiler.
+Lua also compiles unmodified as C++.
+The instructions given below for building Lua are for Unix-like platforms.
+See also
+<A HREF="#other">instructions for other systems</A>
+and
+<A HREF="#customization">customization options</A>.
+
+<P>
+If you don't have the time or the inclination to compile Lua yourself,
+get a binary from
+<A HREF="http://lua-users.org/wiki/LuaBinaries">LuaBinaries</A>.
+Try also
+<A HREF="http://luaforwindows.luaforge.net/">Lua for Windows</A>,
+an easy-to-use distribution of Lua that includes many useful libraries.
+
+<!--
+<P>
+If you only want to try Lua,
+try the
+<A HREF="demo.html">live demo</A>.
+<P>
+-->
+
+<H3>Building Lua</H3>
+
+<P>
+In most Unix-like platforms, simply do "<KBD>make</KBD>" with a suitable target.
+Here are the details.
+
+<OL>
+<LI>
+Open a terminal window and move to
+the top-level directory, which is named lua-5.2.0.
+The Makefile there controls both the build process and the installation process.
+<P>
+<LI>
+  Do "<KBD>make</KBD>" and see if your platform is listed.
+  The platforms currently supported are:
+<BLOCKQUOTE>
+    aix ansi bsd freebsd generic linux macosx mingw posix solaris
+</BLOCKQUOTE>
+<P>
+  If your platform is listed, just do "<KBD>make xxx</KBD>", where xxx
+  is your platform name.
+<P>
+  If your platform is not listed, try the closest one or posix, generic,
+  ansi, in this order.
+<P>
+<LI>
+The compilation takes only a few moments
+and produces three files in the src directory:
+lua (the interpreter),
+luac (the compiler),
+and liblua.a (the library).
+<P>
+<LI>
+  To check that Lua has been built correctly, do "<KBD>make test</KBD>"
+  after building Lua. This will run the interpreter and print its version string.
+</OL>
+
+<H3>Installing Lua</H3>
+<P>
+  Once you have built Lua, you may want to install it in an official
+  place in your system. In this case, do "<KBD>make install</KBD>". The official
+  place and the way to install files are defined in Makefile. You'll
+  probably need the right permissions to install files.
+
+<P>
+  To build and install Lua in one step, do "<KBD>make xxx install</KBD>",
+  where xxx is your platform name.
+
+<P>
+  To install Lua locally, do "<KBD>make local</KBD>".
+  This will create a directory <TT>install</TT> with subdirectories
+  <TT>bin</TT>, <TT>include</TT>, <TT>lib</TT>, <TT>man</TT>,
+  and install Lua as listed below.
+
+  To install Lua locally, but in some other directory, do
+  "<KBD>make install INSTALL_TOP=xxx</KBD>", where xxx is your chosen directory.
+
+<DL CLASS="display">
+<DT>
+    bin:
+<DD>
+    lua luac
+<DT>
+    include:
+<DD>
+    lua.h luaconf.h lualib.h lauxlib.h lua.hpp
+<DT>
+    lib:
+<DD>
+    liblua.a
+<DT>
+    man/man1:
+<DD>
+    lua.1 luac.1
+</DL>
+
+<P>
+  These are the only directories you need for development.
+  If you only want to run Lua programs,
+  you only need the files in bin and man.
+  The files in include and lib are needed for
+  embedding Lua in C or C++ programs.
+
+<H3><A NAME="customization">Customization</A></H3>
+<P>
+  Three kinds of things can be customized by editing a file:
+<UL>
+    <LI> Where and how to install Lua &mdash; edit Makefile.
+    <LI> How to build Lua &mdash; edit src/Makefile.
+    <LI> Lua features &mdash; edit src/luaconf.h.
+</UL>
+
+<P>
+  You don't actually need to edit the Makefiles because you may set the
+  relevant variables in the command line when invoking make.
+  Nevertheless, it's probably best to edit and save the Makefiles to
+  record the changes you need.
+
+<P>
+  On the other hand, if you need to customize some Lua features, you'll need
+  to edit src/luaconf.h before building and installing Lua.
+  The edited file will be the one installed, and
+  it will be used by any Lua clients that you build, to ensure consistency.
+  Further customization is available to experts by editing the Lua sources.
+
+<P>
+  We strongly recommend that you enable dynamic loading in src/luaconf.h.
+  This is done automatically for all platforms listed above that have
+  this feature and also for Windows.
+
+<H3><A NAME="other">Building Lua on other systems</A></H3>
+
+<P>
+  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:
+
+<DL CLASS="display">
+<DT>
+library:
+<DD>
+lapi.c lcode.c lctype.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 lbitlib.c lcorolib.c ldblib.c liolib.c
+lmathlib.c loslib.c lstrlib.c ltablib.c loadlib.c linit.c
+
+<DT>
+interpreter:
+<DD>
+  library, lua.c
+<DT>
+compiler:
+<DD>
+  library, luac.c
+</DL>
+
+<P>
+  To use Lua as a library in your own programs you'll need to know how to
+  create and use libraries with your compiler. Moreover, to dynamically load
+  C libraries for Lua you'll need to know how to create dynamic libraries
+  and you'll need to make sure that the Lua API functions are accessible to
+  those dynamic libraries &mdash; but <EM>don't</EM> link the Lua library
+  into each dynamic library. For Unix, we recommend that the Lua library
+  be linked statically into the host program and its symbols exported for
+  dynamic linking; src/Makefile does this for the Lua interpreter.
+  For Windows, we recommend that the Lua library be a DLL.
+
+<P>
+  As mentioned above, you may edit src/luaconf.h to customize
+  some features before building Lua.
+
+<H2><A NAME="changes">Changes since Lua 5.1</A></H2>
+
+<P>
+Here are the main changes introduced in Lua 5.2.
+The
+<A HREF="contents.html">reference manual</A>
+lists the
+<A HREF="manual.html#8">incompatibilities</A> that had to be introduced.
+
+<H3>Main changes</H3>
+<UL>
+<LI> yieldable pcall and metamethods
+<LI> new lexical scheme for globals
+<LI> ephemeron tables
+<LI> new library for bitwise operations
+<LI> light C functions
+<LI> emergency garbage collector
+<LI> <CODE>goto</CODE> statement
+<LI> finalizers for tables
+</UL>
+
+Here are the other changes introduced in Lua 5.2:
+<H3>Language</H3>
+<UL>
+<LI> no more fenv for threads or functions
+<LI> tables honor the <CODE>__len</CODE> metamethod
+<LI> hex and <CODE>\*</CODE> escapes in strings
+<LI> support for hexadecimal floats
+<LI> order metamethods work for different types
+<LI> no more verification of opcode consistency
+<LI> hook event "tail return" replaced by "tail call"
+<LI> empty statement
+<LI> <CODE>break</CODE> statement may appear in the middle of a block
+</UL>
+
+<H3>Libraries</H3>
+<UL>
+<LI> arguments for function called through <CODE>xpcall</CODE>
+<LI> optional 'mode' argument to load (to control binary x text)
+<LI> optional 'env' argument to load (environment for loaded chunk)
+<LI> <CODE>loadlib</CODE> may load libraries with global names (RTLD_GLOBAL)
+<LI> new function <CODE>package.searchpath</CODE>
+<LI> modules receive their paths when loaded
+<LI> optional base in <CODE>math.log</CODE>
+<LI> optional separator in <CODE>string.rep</CODE>
+<LI> <CODE>file:write</CODE> returns <CODE>file</CODE>
+<LI> closing a pipe returns exit status
+<LI> <CODE>os.exit</CODE> may close state
+<LI> new metamethods <CODE>__pairs</CODE> and <CODE>__ipairs</CODE>
+<LI> new option 'isrunning' for <CODE>collectgarbage</CODE> and <CODE>lua_gc</CODE>
+<LI> frontier patterns
+<LI> <CODE>\0</CODE> in patterns
+<LI> new option <CODE>*L</CODE> for <CODE>io.read</CODE>
+<LI> options for <CODE>io.lines</CODE>
+<LI> <CODE>debug.getlocal</CODE> can access function varargs
+</UL>
+
+<H3>C API</H3>
+<UL>
+<LI> main thread predefined in the registry
+<LI> new constants <CODE>LUA_OK</CODE> and <CODE>LUA_ERRGCMM</CODE>
+<LI> new <CODE>lua_compare</CODE>, <CODE>lua_arith</CODE>, and <CODE>lua_len</CODE>
+<LI> new <CODE>lua_version</CODE> and <CODE>luaL_checkversion</CODE>
+<LI> <CODE>lua_pushstring</CODE> and <CODE>pushlstring</CODE> return string
+<LI> new <CODE>luaL_testudata</CODE> and <CODE>luaL_setmetatable</CODE>
+<LI> new <CODE>luaL_tolstring</CODE>
+<LI> new <CODE>lua_copy</CODE>
+<LI> new <CODE>lua_absindex</CODE>
+<LI> new <CODE>lua_upvalueid</CODE> and <CODE>lua_upvaluejoin</CODE>
+<LI> <CODE>nparams</CODE> and <CODE>isvararg</CODE> available in debug API
+<LI> new <CODE>lua_Unsigned</CODE>
+</UL>
+
+<H3>Implementation</H3>
+<UL>
+<LI> max constants per function raised to 2<SUP>26</SUP>
+<LI> internal (immutable) version of ctypes
+<LI> simpler implementation for string buffers
+<LI> udata with finalizers are kept in a separated list for the GC
+<LI> <CODE>CallInfo</CODE> stack now is a linked list
+<LI> parser uses much less C-stack space (no more auto arrays)
+<LI> new hash for floats
+<LI> handling of non-string error messages in the standalone interpreter
+<LI> generational mode for garbage collection (experimental)
+<LI> NaN trick (experimental)
+</UL>
+
+<H2><A NAME="license">License</A></H2>
+<A HREF="http://www.opensource.org/docs/definition.php">
+<IMG SRC="osi-certified-72x60.png" ALIGN="right" BORDER="0" ALT="[osi certified]" STYLE="padding-left: 30px ;">
+</A>
+
+<P>
+Lua is free software distributed under the terms of the
+<A HREF="http://www.opensource.org/licenses/mit-license.html">MIT license</A>
+reproduced below;
+it may be used for any purpose, including commercial purposes,
+at absolutely no cost without having to ask us.
+
+The only requirement is that if you do use Lua,
+then you should give us credit by including the appropriate copyright notice somewhere in your product or its documentation.
+
+For details, see
+<A HREF="http://www.lua.org/license.html">this</A>.
+
+<BLOCKQUOTE>
+Copyright &copy; 1994&ndash;2011 Lua.org, PUC-Rio.
+
+<P>
+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:
+
+<P>
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
 <P>
+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.
+</BLOCKQUOTE>
 
 <HR>
-<SMALL>
+<SMALL CLASS="footer">
 Last update:
-Tue Aug 12 14:46:07 BRT 2008
+Fri Jun 24 11:30:57 BRT 2011
 </SMALL>
+<!--
+Last change: revised for Lua 5.2.0 (beta)
+-->
 
 </BODY>
 </HTML>
diff --git a/etc/Makefile b/etc/Makefile
deleted file mode 100644
index 6d00008..0000000
--- a/etc/Makefile
+++ /dev/null
@@ -1,44 +0,0 @@
-# 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/etc/README b/etc/README
deleted file mode 100644
index 5149fc9..0000000
--- a/etc/README
+++ /dev/null
@@ -1,37 +0,0 @@
-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/etc/all.c b/etc/all.c
deleted file mode 100644
index dab68fa..0000000
--- a/etc/all.c
+++ /dev/null
@@ -1,38 +0,0 @@
-/*
-* 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/etc/lua.pc b/etc/lua.pc
deleted file mode 100644
index f52f55b..0000000
--- a/etc/lua.pc
+++ /dev/null
@@ -1,31 +0,0 @@
-# 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/etc/luavs.bat b/etc/luavs.bat
deleted file mode 100644
index 08c2bed..0000000
--- a/etc/luavs.bat
+++ /dev/null
@@ -1,28 +0,0 @@
-@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/etc/min.c b/etc/min.c
deleted file mode 100644
index 6a85a4d..0000000
--- a/etc/min.c
+++ /dev/null
@@ -1,39 +0,0 @@
-/*
-* 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/etc/noparser.c b/etc/noparser.c
deleted file mode 100644
index 13ba546..0000000
--- a/etc/noparser.c
+++ /dev/null
@@ -1,50 +0,0 @@
-/*
-* 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/etc/strict.lua b/etc/strict.lua
deleted file mode 100644
index 604619d..0000000
--- a/etc/strict.lua
+++ /dev/null
@@ -1,41 +0,0 @@
---
--- 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/src/Makefile b/src/Makefile
index e4a3cd6..a77f35d 100644..100755
--- a/src/Makefile
+++ b/src/Makefile
@@ -1,6 +1,5 @@
-# makefile for building Lua
-# see ../INSTALL for installation instructions
-# see ../Makefile and luaconf.h for further customization
+# Makefile for building Lua
+# See ../doc/readme.html for installation and customization instructions.
 
 # == CHANGE THE SETTINGS BELOW TO SUIT YOUR ENVIRONMENT =======================
 
@@ -8,37 +7,46 @@
 PLAT= none
 
 CC= gcc
-CFLAGS= -O2 -Wall $(MYCFLAGS)
+CFLAGS= -O2 -Wall -DLUA_COMPAT_ALL $(SYSCFLAGS) $(MYCFLAGS)
+LDFLAGS= $(SYSLDFLAGS) $(MYLDFLAGS)
+LIBS= -lm $(SYSLIBS) $(MYLIBS)
+
 AR= ar rcu
 RANLIB= ranlib
 RM= rm -f
-LIBS= -lm $(MYLIBS)
+
+SYSCFLAGS=
+SYSLDFLAGS=
+SYSLIBS=
 
 MYCFLAGS=
 MYLDFLAGS=
 MYLIBS=
+MYOBJS=
 
-# == END OF USER SETTINGS. NO NEED TO CHANGE ANYTHING BELOW THIS LINE =========
+# == 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
+CORE_O=	lapi.o lcode.o lctype.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 lbitlib.o lcorolib.o ldblib.o liolib.o \
+	lmathlib.o loslib.o lstrlib.o ltablib.o loadlib.o linit.o
+BASE_O= $(CORE_O) $(LIB_O) $(MYOBJS)
 
 LUA_T=	lua
 LUA_O=	lua.o
 
 LUAC_T=	luac
-LUAC_O=	luac.o print.o
+LUAC_O=	luac.o
 
-ALL_O= $(CORE_O) $(LIB_O) $(LUA_O) $(LUAC_O)
+ALL_O= $(BASE_O) $(LUA_O) $(LUAC_O)
 ALL_T= $(LUA_A) $(LUA_T) $(LUAC_T)
 ALL_A= $(LUA_A)
 
+# Targets start here.
 default: $(PLAT)
 
 all:	$(ALL_T)
@@ -47,136 +55,132 @@ o:	$(ALL_O)
 
 a:	$(ALL_A)
 
-$(LUA_A): $(CORE_O) $(LIB_O)
+$(LUA_A): $(BASE_O)
 	$(AR) $@ $?
 	$(RANLIB) $@
 
 $(LUA_T): $(LUA_O) $(LUA_A)
-	$(CC) -o $@ $(MYLDFLAGS) $(LUA_O) $(LUA_A) $(LIBS)
+	$(CC) -o $@ $(LDFLAGS) $(LUA_O) $(LUA_A) $(LIBS)
 
 $(LUAC_T): $(LUAC_O) $(LUA_A)
-	$(CC) -o $@ $(MYLDFLAGS) $(LUAC_O) $(LUA_A) $(LIBS)
+	$(CC) -o $@ $(LDFLAGS) $(LUAC_O) $(LUA_A) $(LIBS)
 
 clean:
 	$(RM) $(ALL_T) $(ALL_O)
 
 depend:
-	@$(CC) $(CFLAGS) -MM l*.c print.c
+	@$(CC) $(CFLAGS) -MM l*.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
+	@echo "PLAT= $(PLAT)"
+	@echo "CC= $(CC)"
+	@echo "CFLAGS= $(CFLAGS)"
+	@echo "LDFLAGS= $(SYSLDFLAGS)"
+	@echo "LIBS= $(LIBS)"
+	@echo "AR= $(AR)"
+	@echo "RANLIB= $(RANLIB)"
+	@echo "RM= $(RM)"
+
+# Convenience targets for popular platforms
+ALL= all
 
 none:
-	@echo "Please choose a platform:"
+	@echo "Please do 'make PLATFORM' where PLATFORM is one of these:"
 	@echo "   $(PLATS)"
 
 aix:
-	$(MAKE) all CC="xlc" CFLAGS="-O2 -DLUA_USE_POSIX -DLUA_USE_DLOPEN" MYLIBS="-ldl" MYLDFLAGS="-brtl -bexpall"
+	$(MAKE) $(ALL) CC="xlc" CFLAGS="-O2 -DLUA_USE_POSIX -DLUA_USE_DLOPEN" SYSLIBS="-ldl" SYSLDFLAGS="-brtl -bexpall"
 
 ansi:
-	$(MAKE) all MYCFLAGS=-DLUA_ANSI
+	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_ANSI"
 
 bsd:
-	$(MAKE) all MYCFLAGS="-DLUA_USE_POSIX -DLUA_USE_DLOPEN" MYLIBS="-Wl,-E"
+	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_POSIX -DLUA_USE_DLOPEN" SYSLIBS="-Wl,-E"
 
 freebsd:
-	$(MAKE) all MYCFLAGS="-DLUA_USE_LINUX" MYLIBS="-Wl,-E -lreadline"
+	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_LINUX" SYSLIBS="-Wl,-E -lreadline"
 
-generic:
-	$(MAKE) all MYCFLAGS=
+generic: $(ALL)
 
 linux:
-	$(MAKE) all MYCFLAGS=-DLUA_USE_LINUX MYLIBS="-Wl,-E -ldl -lreadline -lhistory -lncurses"
+	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_LINUX" SYSLIBS="-Wl,-E -ldl -lreadline -lncurses"
 
 macosx:
-	$(MAKE) all MYCFLAGS=-DLUA_USE_LINUX MYLIBS="-lreadline"
-# use this on Mac OS X 10.3-
-#	$(MAKE) all MYCFLAGS=-DLUA_USE_MACOSX
+	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_MACOSX" SYSLIBS="-lreadline"
 
 mingw:
-	$(MAKE) "LUA_A=lua51.dll" "LUA_T=lua.exe" \
+	$(MAKE) "LUA_A=lua52.dll" "LUA_T=lua.exe" \
 	"AR=$(CC) -shared -o" "RANLIB=strip --strip-unneeded" \
-	"MYCFLAGS=-DLUA_BUILD_AS_DLL" "MYLIBS=" "MYLDFLAGS=-s" lua.exe
-	$(MAKE) "LUAC_T=luac.exe" luac.exe
+	"SYSCFLAGS=-DLUA_BUILD_AS_DLL" "SYSLIBS=" "SYSLDFLAGS=-s" lua.exe
 
 posix:
-	$(MAKE) all MYCFLAGS=-DLUA_USE_POSIX
+	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_POSIX"
 
 solaris:
-	$(MAKE) all MYCFLAGS="-DLUA_USE_POSIX -DLUA_USE_DLOPEN" MYLIBS="-ldl"
+	$(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_POSIX -DLUA_USE_DLOPEN" SYSLIBS="-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
+lapi.o: lapi.c lua.h luaconf.h lapi.h llimits.h lstate.h lobject.h ltm.h \
+ lzio.h lmem.h ldebug.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
+lbitlib.o: lbitlib.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
+ lzio.h lmem.h lopcodes.h lparser.h ldebug.h lstate.h ltm.h ldo.h lgc.h \
+ lstring.h ltable.h lvm.h
+lcorolib.o: lcorolib.c lua.h luaconf.h lauxlib.h lualib.h
+lctype.o: lctype.c lctype.h lua.h luaconf.h llimits.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
+ldebug.o: ldebug.c lua.h luaconf.h lapi.h llimits.h lstate.h lobject.h \
+ ltm.h lzio.h lmem.h lcode.h llex.h lopcodes.h lparser.h ldebug.h ldo.h \
+ lfunc.h lstring.h lgc.h ltable.h lvm.h
+ldo.o: ldo.c lua.h luaconf.h lapi.h llimits.h lstate.h lobject.h ltm.h \
+ lzio.h lmem.h ldebug.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
+ lzio.h lmem.h lundump.h
+lfunc.o: lfunc.c lua.h luaconf.h lfunc.h lobject.h llimits.h lgc.h \
+ lstate.h ltm.h lzio.h lmem.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
+ 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
+llex.o: llex.c lua.h luaconf.h lctype.h llimits.h ldo.h lobject.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
+ ltm.h lzio.h lmem.h ldo.h lgc.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
+lobject.o: lobject.c lua.h luaconf.h lctype.h llimits.h ldebug.h lstate.h \
+ lobject.h ltm.h lzio.h lmem.h ldo.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
+ 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 lapi.h llimits.h lstate.h lobject.h \
+ ltm.h lzio.h lmem.h ldebug.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
+ 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
+ ltm.h lzio.h lmem.h ldo.h lgc.h lstring.h ltable.h lvm.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
+ 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
+luac.o: luac.c lua.h luaconf.h lauxlib.h lobject.h llimits.h lstate.h \
+ ltm.h lzio.h lmem.h lundump.h ldebug.h lopcodes.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
+ 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.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
+ lzio.h
 
-# (end of Makefile)
diff --git a/src/lapi.c b/src/lapi.c
index 5d5145d..7761419 100644..100755
--- a/src/lapi.c
+++ b/src/lapi.c
@@ -1,12 +1,10 @@
 /*
-** $Id: lapi.c,v 2.55.1.5 2008/07/04 18:41:18 roberto Exp $
+** $Id: lapi.c,v 2.149 2011/06/13 14:13:06 roberto Exp $
 ** Lua API
 ** See Copyright Notice in lua.h
 */
 
 
-#include <assert.h>
-#include <math.h>
 #include <stdarg.h>
 #include <string.h>
 
@@ -32,76 +30,69 @@
 
 
 const char lua_ident[] =
-  "$Lua: " LUA_RELEASE " " LUA_COPYRIGHT " $\n"
-  "$Authors: " LUA_AUTHORS " $\n"
-  "$URL: www.lua.org $\n";
+  "$LuaVersion: " LUA_COPYRIGHT " $"
+  "$LuaAuthors: " LUA_AUTHORS " $";
 
 
 
-#define api_checknelems(L, n)	api_check(L, (n) <= (L->top - L->base))
+#define api_checkvalidindex(L, i)	api_check(L, (i) != luaO_nilobject, \
+					  "invalid index")
 
-#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) {
+static TValue *index2addr (lua_State *L, int idx) {
+  CallInfo *ci = L->ci;
   if (idx > 0) {
-    TValue *o = L->base + (idx - 1);
-    api_check(L, idx <= L->ci->top - L->base);
+    TValue *o = ci->func + idx;
+    api_check(L, idx <= ci->top - (ci->func + 1), "unacceptable index");
     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);
+    api_check(L, idx != 0 && -idx <= L->top - (ci->func + 1), "invalid index");
     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);
+  else if (idx == LUA_REGISTRYINDEX)
+    return &G(L)->l_registry;
+  else {  /* upvalues */
+    idx = LUA_REGISTRYINDEX - idx;
+    api_check(L, idx <= MAXUPVAL + 1, "upvalue index too large");
+    if (ttislcf(ci->func))  /* light C function? */
+      return cast(TValue *, luaO_nilobject);  /* it has no upvalues */
+    else {
+      CClosure *func = clCvalue(ci->func);
+      return (idx <= func->nupvalues)
+             ? &func->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);
+/*
+** to be called by 'lua_checkstack' in protected mode, to grow stack
+** capturing memory errors
+*/
+static void growstack (lua_State *L, void *ud) {
+  int size = *(int *)ud;
+  luaD_growstack(L, size);
 }
 
 
 LUA_API int lua_checkstack (lua_State *L, int size) {
-  int res = 1;
+  int res;
+  CallInfo *ci = L->ci;
   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;
+  if (L->stack_last - L->top > size)  /* stack large enough? */
+    res = 1;  /* yes; check is OK */
+  else {  /* no; need to grow stack */
+    int inuse = cast_int(L->top - L->stack) + EXTRA_STACK;
+    if (inuse > LUAI_MAXSTACK - size)  /* can grow without overflow? */
+      res = 0;  /* no */
+    else  /* try to grow stack */
+      res = (luaD_rawrunprotected(L, &growstack, &size) == LUA_OK);
   }
+  if (res && ci->top < L->top + size)
+    ci->top = L->top + size;  /* adjust frame top */
   lua_unlock(L);
   return res;
 }
@@ -112,8 +103,8 @@ LUA_API void lua_xmove (lua_State *from, lua_State *to, int n) {
   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);
+  api_check(from, G(from) == G(to), "moving among independent states");
+  api_check(from, to->ci->top - to->top >= n, "not enough elements to move");
   from->top -= n;
   for (i = 0; i < n; i++) {
     setobj2s(to, to->top++, from->top + i);
@@ -122,11 +113,6 @@ LUA_API void lua_xmove (lua_State *from, lua_State *to, int n) {
 }
 
 
-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);
@@ -137,16 +123,10 @@ LUA_API lua_CFunction lua_atpanic (lua_State *L, lua_CFunction panicf) {
 }
 
 
-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;
+LUA_API const lua_Number *lua_version (lua_State *L) {
+  static const lua_Number version = LUA_VERSION_NUM;
+  if (L == NULL) return &version;
+  else return G(L)->version;
 }
 
 
@@ -156,21 +136,32 @@ LUA_API lua_State *lua_newthread (lua_State *L) {
 */
 
 
+/*
+** convert an acceptable stack index into an absolute index
+*/
+LUA_API int lua_absindex (lua_State *L, int idx) {
+  return (idx > 0 || idx <= LUA_REGISTRYINDEX)
+         ? idx
+         : cast_int(L->top - L->ci->func + idx);
+}
+
+
 LUA_API int lua_gettop (lua_State *L) {
-  return cast_int(L->top - L->base);
+  return cast_int(L->top - (L->ci->func + 1));
 }
 
 
 LUA_API void lua_settop (lua_State *L, int idx) {
+  StkId func = L->ci->func;
   lua_lock(L);
   if (idx >= 0) {
-    api_check(L, idx <= L->stack_last - L->base);
-    while (L->top < L->base + idx)
+    api_check(L, idx <= L->stack_last - (func + 1), "new top too large");
+    while (L->top < (func + 1) + idx)
       setnilvalue(L->top++);
-    L->top = L->base + idx;
+    L->top = (func + 1) + idx;
   }
   else {
-    api_check(L, -(idx+1) <= (L->top - L->base));
+    api_check(L, -(idx+1) <= (L->top - (func + 1)), "invalid new top");
     L->top += idx+1;  /* `subtract' index (index is negative) */
   }
   lua_unlock(L);
@@ -180,7 +171,7 @@ LUA_API void lua_settop (lua_State *L, int idx) {
 LUA_API void lua_remove (lua_State *L, int idx) {
   StkId p;
   lua_lock(L);
-  p = index2adr(L, idx);
+  p = index2addr(L, idx);
   api_checkvalidindex(L, p);
   while (++p < L->top) setobjs2s(L, p-1, p);
   L->top--;
@@ -192,7 +183,7 @@ LUA_API void lua_insert (lua_State *L, int idx) {
   StkId p;
   StkId q;
   lua_lock(L);
-  p = index2adr(L, idx);
+  p = index2addr(L, idx);
   api_checkvalidindex(L, p);
   for (q = L->top; q>p; q--) setobjs2s(L, q, q-1);
   setobjs2s(L, p, L->top);
@@ -200,34 +191,39 @@ LUA_API void lua_insert (lua_State *L, int idx) {
 }
 
 
+static void moveto (lua_State *L, TValue *fr, int idx) {
+  TValue *to = index2addr(L, idx);
+  api_checkvalidindex(L, to);
+  setobj(L, to, fr);
+  if (idx < LUA_REGISTRYINDEX)  /* function upvalue? */
+    luaC_barrier(L, clCvalue(L->ci->func), fr);
+  /* LUA_REGISTRYINDEX does not need gc barrier
+     (collector revisits it before finishing collection) */
+}
+
+
 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);
-  }
+  moveto(L, L->top - 1, idx);
   L->top--;
   lua_unlock(L);
 }
 
 
+LUA_API void lua_copy (lua_State *L, int fromidx, int toidx) {
+  TValue *fr;
+  lua_lock(L);
+  fr = index2addr(L, fromidx);
+  api_checkvalidindex(L, fr);
+  moveto(L, fr, toidx);
+  lua_unlock(L);
+}
+
+
 LUA_API void lua_pushvalue (lua_State *L, int idx) {
   lua_lock(L);
-  setobj2s(L, L->top, index2adr(L, idx));
+  setobj2s(L, L->top, index2addr(L, idx));
   api_incr_top(L);
   lua_unlock(L);
 }
@@ -240,26 +236,26 @@ LUA_API void lua_pushvalue (lua_State *L, int idx) {
 
 
 LUA_API int lua_type (lua_State *L, int idx) {
-  StkId o = index2adr(L, idx);
-  return (o == luaO_nilobject) ? LUA_TNONE : ttype(o);
+  StkId o = index2addr(L, idx);
+  return (o == luaO_nilobject) ? LUA_TNONE : ttypenv(o);
 }
 
 
 LUA_API const char *lua_typename (lua_State *L, int t) {
   UNUSED(L);
-  return (t == LUA_TNONE) ? "no value" : luaT_typenames[t];
+  return ttypename(t);
 }
 
 
 LUA_API int lua_iscfunction (lua_State *L, int idx) {
-  StkId o = index2adr(L, idx);
-  return iscfunction(o);
+  StkId o = index2addr(L, idx);
+  return (ttislcf(o) || (ttisCclosure(o)));
 }
 
 
 LUA_API int lua_isnumber (lua_State *L, int idx) {
   TValue n;
-  const TValue *o = index2adr(L, idx);
+  const TValue *o = index2addr(L, idx);
   return tonumber(o, &n);
 }
 
@@ -271,77 +267,117 @@ LUA_API int lua_isstring (lua_State *L, int idx) {
 
 
 LUA_API int lua_isuserdata (lua_State *L, int idx) {
-  const TValue *o = index2adr(L, idx);
+  const TValue *o = index2addr(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);
+  StkId o1 = index2addr(L, index1);
+  StkId o2 = index2addr(L, index2);
   return (o1 == luaO_nilobject || o2 == luaO_nilobject) ? 0
-         : luaO_rawequalObj(o1, o2);
+         : luaV_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_API void  lua_arith (lua_State *L, int op) {
+  StkId o1;  /* 1st operand */
+  StkId o2;  /* 2nd operand */
+  lua_lock(L);
+  if (op != LUA_OPUNM) /* all other operations expect two operands */
+    api_checknelems(L, 2);
+  else {  /* for unary minus, add fake 2nd operand */
+    api_checknelems(L, 1);
+    setobjs2s(L, L->top, L->top - 1);
+    L->top++;
+  }
+  o1 = L->top - 2;
+  o2 = L->top - 1;
+  if (ttisnumber(o1) && ttisnumber(o2)) {
+    changenvalue(o1, luaO_arith(op, nvalue(o1), nvalue(o2)));
+  }
+  else
+    luaV_arith(L, o1, o1, o2, cast(TMS, op - LUA_OPADD + TM_ADD));
+  L->top--;
   lua_unlock(L);
-  return i;
 }
 
 
-LUA_API int lua_lessthan (lua_State *L, int index1, int index2) {
+LUA_API int lua_compare (lua_State *L, int index1, int index2, int op) {
   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);
+  o1 = index2addr(L, index1);
+  o2 = index2addr(L, index2);
+  if (o1 == luaO_nilobject || o2 == luaO_nilobject)
+    i = 0;
+  else switch (op) {
+    case LUA_OPEQ: i = equalobj(L, o1, o2); break;
+    case LUA_OPLT: i = luaV_lessthan(L, o1, o2); break;
+    case LUA_OPLE: i = luaV_lessequal(L, o1, o2); break;
+    default: api_check(L, 0, "invalid option"); i = 0;
+  }
   lua_unlock(L);
   return i;
 }
 
 
-
-LUA_API lua_Number lua_tonumber (lua_State *L, int idx) {
+LUA_API lua_Number lua_tonumberx (lua_State *L, int idx, int *isnum) {
   TValue n;
-  const TValue *o = index2adr(L, idx);
-  if (tonumber(o, &n))
+  const TValue *o = index2addr(L, idx);
+  if (tonumber(o, &n)) {
+    if (isnum) *isnum = 1;
     return nvalue(o);
-  else
+  }
+  else {
+    if (isnum) *isnum = 0;
     return 0;
+  }
 }
 
 
-LUA_API lua_Integer lua_tointeger (lua_State *L, int idx) {
+LUA_API lua_Integer lua_tointegerx (lua_State *L, int idx, int *isnum) {
   TValue n;
-  const TValue *o = index2adr(L, idx);
+  const TValue *o = index2addr(L, idx);
   if (tonumber(o, &n)) {
     lua_Integer res;
     lua_Number num = nvalue(o);
     lua_number2integer(res, num);
+    if (isnum) *isnum = 1;
     return res;
   }
-  else
+  else {
+    if (isnum) *isnum = 0;
+    return 0;
+  }
+}
+
+
+LUA_API lua_Unsigned lua_tounsignedx (lua_State *L, int idx, int *isnum) {
+  TValue n;
+  const TValue *o = index2addr(L, idx);
+  if (tonumber(o, &n)) {
+    lua_Unsigned res;
+    lua_Number num = nvalue(o);
+    lua_number2unsigned(res, num);
+    if (isnum) *isnum = 1;
+    return res;
+  }
+  else {
+    if (isnum) *isnum = 0;
     return 0;
+  }
 }
 
 
 LUA_API int lua_toboolean (lua_State *L, int idx) {
-  const TValue *o = index2adr(L, idx);
+  const TValue *o = index2addr(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);
+  StkId o = index2addr(L, idx);
   if (!ttisstring(o)) {
     lua_lock(L);  /* `luaV_tostring' may create a new string */
     if (!luaV_tostring(L, o)) {  /* conversion failed? */
@@ -350,7 +386,7 @@ LUA_API const char *lua_tolstring (lua_State *L, int idx, size_t *len) {
       return NULL;
     }
     luaC_checkGC(L);
-    o = index2adr(L, idx);  /* previous call may reallocate the stack */
+    o = index2addr(L, idx);  /* previous call may reallocate the stack */
     lua_unlock(L);
   }
   if (len != NULL) *len = tsvalue(o)->len;
@@ -358,33 +394,29 @@ LUA_API const char *lua_tolstring (lua_State *L, int idx, size_t *len) {
 }
 
 
-LUA_API size_t lua_objlen (lua_State *L, int idx) {
-  StkId o = index2adr(L, idx);
-  switch (ttype(o)) {
+LUA_API size_t lua_rawlen (lua_State *L, int idx) {
+  StkId o = index2addr(L, idx);
+  switch (ttypenv(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;
+  StkId o = index2addr(L, idx);
+  if (ttislcf(o)) return fvalue(o);
+  else if (ttisCclosure(o))
+    return clCvalue(o)->f;
+  else return NULL;  /* not a C function */
 }
 
 
 LUA_API void *lua_touserdata (lua_State *L, int idx) {
-  StkId o = index2adr(L, idx);
-  switch (ttype(o)) {
+  StkId o = index2addr(L, idx);
+  switch (ttypenv(o)) {
     case LUA_TUSERDATA: return (rawuvalue(o) + 1);
     case LUA_TLIGHTUSERDATA: return pvalue(o);
     default: return NULL;
@@ -393,16 +425,18 @@ LUA_API void *lua_touserdata (lua_State *L, int idx) {
 
 
 LUA_API lua_State *lua_tothread (lua_State *L, int idx) {
-  StkId o = index2adr(L, idx);
+  StkId o = index2addr(L, idx);
   return (!ttisthread(o)) ? NULL : thvalue(o);
 }
 
 
 LUA_API const void *lua_topointer (lua_State *L, int idx) {
-  StkId o = index2adr(L, idx);
+  StkId o = index2addr(L, idx);
   switch (ttype(o)) {
     case LUA_TTABLE: return hvalue(o);
-    case LUA_TFUNCTION: return clvalue(o);
+    case LUA_TLCL: return clLvalue(o);
+    case LUA_TCCL: return clCvalue(o);
+    case LUA_TLCF: return cast(void *, cast(size_t, fvalue(o)));
     case LUA_TTHREAD: return thvalue(o);
     case LUA_TUSERDATA:
     case LUA_TLIGHTUSERDATA:
@@ -429,6 +463,8 @@ LUA_API void lua_pushnil (lua_State *L) {
 LUA_API void lua_pushnumber (lua_State *L, lua_Number n) {
   lua_lock(L);
   setnvalue(L->top, n);
+  luai_checknum(L, L->top,
+    luaG_runerror(L, "C API - attempt to push a signaling NaN"));
   api_incr_top(L);
   lua_unlock(L);
 }
@@ -442,20 +478,43 @@ LUA_API void lua_pushinteger (lua_State *L, lua_Integer n) {
 }
 
 
-LUA_API void lua_pushlstring (lua_State *L, const char *s, size_t len) {
+LUA_API void lua_pushunsigned (lua_State *L, lua_Unsigned u) {
+  lua_Number n;
+  lua_lock(L);
+  n = lua_unsigned2number(u);
+  setnvalue(L->top, n);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API const char *lua_pushlstring (lua_State *L, const char *s, size_t len) {
+  TString *ts;
   lua_lock(L);
   luaC_checkGC(L);
-  setsvalue2s(L, L->top, luaS_newlstr(L, s, len));
+  ts = luaS_newlstr(L, s, len);
+  setsvalue2s(L, L->top, ts);
   api_incr_top(L);
   lua_unlock(L);
+  return getstr(ts);
 }
 
 
-LUA_API void lua_pushstring (lua_State *L, const char *s) {
-  if (s == NULL)
+LUA_API const char *lua_pushstring (lua_State *L, const char *s) {
+  if (s == NULL) {
     lua_pushnil(L);
-  else
-    lua_pushlstring(L, s, strlen(s));
+    return NULL;
+  }
+  else {
+    TString *ts;
+    lua_lock(L);
+    luaC_checkGC(L);
+    ts = luaS_new(L, s);
+    setsvalue2s(L, L->top, ts);
+    api_incr_top(L);
+    lua_unlock(L);
+    return getstr(ts);
+  }
 }
 
 
@@ -484,17 +543,22 @@ LUA_API const char *lua_pushfstring (lua_State *L, const char *fmt, ...) {
 
 
 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)));
+  if (n == 0) {
+    setfvalue(L->top, fn);
+  }
+  else {
+    Closure *cl;
+    api_checknelems(L, n);
+    api_check(L, n <= MAXUPVAL, "upvalue index too large");
+    luaC_checkGC(L);
+    cl = luaF_newCclosure(L, n);
+    cl->c.f = fn;
+    L->top -= n;
+    while (n--)
+      setobj2n(L, &cl->c.upvalue[n], L->top + n);
+    setclCvalue(L, L->top, cl);
+  }
   api_incr_top(L);
   lua_unlock(L);
 }
@@ -534,7 +598,7 @@ LUA_API int lua_pushthread (lua_State *L) {
 LUA_API void lua_gettable (lua_State *L, int idx) {
   StkId t;
   lua_lock(L);
-  t = index2adr(L, idx);
+  t = index2addr(L, idx);
   api_checkvalidindex(L, t);
   luaV_gettable(L, t, L->top - 1, L->top - 1);
   lua_unlock(L);
@@ -543,13 +607,12 @@ LUA_API void lua_gettable (lua_State *L, int idx) {
 
 LUA_API void lua_getfield (lua_State *L, int idx, const char *k) {
   StkId t;
-  TValue key;
   lua_lock(L);
-  t = index2adr(L, idx);
+  t = index2addr(L, idx);
   api_checkvalidindex(L, t);
-  setsvalue(L, &key, luaS_new(L, k));
-  luaV_gettable(L, t, &key, L->top);
+  setsvalue2s(L, L->top, luaS_new(L, k));
   api_incr_top(L);
+  luaV_gettable(L, t, L->top - 1, L->top - 1);
   lua_unlock(L);
 }
 
@@ -557,8 +620,8 @@ LUA_API void lua_getfield (lua_State *L, int idx, const char *k) {
 LUA_API void lua_rawget (lua_State *L, int idx) {
   StkId t;
   lua_lock(L);
-  t = index2adr(L, idx);
-  api_check(L, ttistable(t));
+  t = index2addr(L, idx);
+  api_check(L, ttistable(t), "table expected");
   setobj2s(L, L->top - 1, luaH_get(hvalue(t), L->top - 1));
   lua_unlock(L);
 }
@@ -567,19 +630,23 @@ LUA_API void lua_rawget (lua_State *L, int idx) {
 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));
+  o = index2addr(L, idx);
+  api_check(L, ttistable(o), "table expected");
+  setobj2s(L, L->top, luaH_getint(hvalue(o), n));
   api_incr_top(L);
   lua_unlock(L);
 }
 
 
 LUA_API void lua_createtable (lua_State *L, int narray, int nrec) {
+  Table *t;
   lua_lock(L);
   luaC_checkGC(L);
-  sethvalue(L, L->top, luaH_new(L, narray, nrec));
+  t = luaH_new(L);
+  sethvalue(L, L->top, t);
   api_incr_top(L);
+  if (narray > 0 || nrec > 0)
+    luaH_resize(L, t, narray, nrec);
   lua_unlock(L);
 }
 
@@ -589,8 +656,8 @@ LUA_API int lua_getmetatable (lua_State *L, int objindex) {
   Table *mt = NULL;
   int res;
   lua_lock(L);
-  obj = index2adr(L, objindex);
-  switch (ttype(obj)) {
+  obj = index2addr(L, objindex);
+  switch (ttypenv(obj)) {
     case LUA_TTABLE:
       mt = hvalue(obj)->metatable;
       break;
@@ -598,7 +665,7 @@ LUA_API int lua_getmetatable (lua_State *L, int objindex) {
       mt = uvalue(obj)->metatable;
       break;
     default:
-      mt = G(L)->mt[ttype(obj)];
+      mt = G(L)->mt[ttypenv(obj)];
       break;
   }
   if (mt == NULL)
@@ -613,25 +680,16 @@ LUA_API int lua_getmetatable (lua_State *L, int objindex) {
 }
 
 
-LUA_API void lua_getfenv (lua_State *L, int idx) {
+LUA_API void lua_getuservalue (lua_State *L, int idx) {
   StkId o;
   lua_lock(L);
-  o = index2adr(L, idx);
+  o = index2addr(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_check(L, ttisuserdata(o), "userdata expected");
+  if (uvalue(o)->env) {
+    sethvalue(L, L->top, uvalue(o)->env);
+  } else
+    setnilvalue(L->top);
   api_incr_top(L);
   lua_unlock(L);
 }
@@ -646,7 +704,7 @@ LUA_API void lua_settable (lua_State *L, int idx) {
   StkId t;
   lua_lock(L);
   api_checknelems(L, 2);
-  t = index2adr(L, idx);
+  t = index2addr(L, idx);
   api_checkvalidindex(L, t);
   luaV_settable(L, t, L->top - 2, L->top - 1);
   L->top -= 2;  /* pop index and value */
@@ -656,14 +714,13 @@ LUA_API void lua_settable (lua_State *L, int idx) {
 
 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);
+  t = index2addr(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 */
+  setsvalue2s(L, L->top++, luaS_new(L, k));
+  luaV_settable(L, t, L->top - 1, L->top - 2);
+  L->top -= 2;  /* pop value and key */
   lua_unlock(L);
 }
 
@@ -672,10 +729,10 @@ 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));
+  t = index2addr(L, idx);
+  api_check(L, ttistable(t), "table expected");
   setobj2t(L, luaH_set(L, hvalue(t), L->top-2), L->top-1);
-  luaC_barriert(L, hvalue(t), L->top-1);
+  luaC_barrierback(L, gcvalue(t), L->top-1);
   L->top -= 2;
   lua_unlock(L);
 }
@@ -685,10 +742,10 @@ 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);
+  o = index2addr(L, idx);
+  api_check(L, ttistable(o), "table expected");
+  setobj2t(L, luaH_setint(L, hvalue(o), n), L->top-1);
+  luaC_barrierback(L, gcvalue(o), L->top-1);
   L->top--;
   lua_unlock(L);
 }
@@ -699,29 +756,32 @@ LUA_API int lua_setmetatable (lua_State *L, int objindex) {
   Table *mt;
   lua_lock(L);
   api_checknelems(L, 1);
-  obj = index2adr(L, objindex);
+  obj = index2addr(L, objindex);
   api_checkvalidindex(L, obj);
   if (ttisnil(L->top - 1))
     mt = NULL;
   else {
-    api_check(L, ttistable(L->top - 1));
+    api_check(L, ttistable(L->top - 1), "table expected");
     mt = hvalue(L->top - 1);
   }
-  switch (ttype(obj)) {
+  switch (ttypenv(obj)) {
     case LUA_TTABLE: {
       hvalue(obj)->metatable = mt;
       if (mt)
-        luaC_objbarriert(L, hvalue(obj), mt);
+        luaC_objbarrierback(L, gcvalue(obj), mt);
+        luaC_checkfinalizer(L, gcvalue(obj), mt);
       break;
     }
     case LUA_TUSERDATA: {
       uvalue(obj)->metatable = mt;
-      if (mt)
+      if (mt) {
         luaC_objbarrier(L, rawuvalue(obj), mt);
+        luaC_checkfinalizer(L, gcvalue(obj), mt);
+      }
       break;
     }
     default: {
-      G(L)->mt[ttype(obj)] = mt;
+      G(L)->mt[ttypenv(obj)] = mt;
       break;
     }
   }
@@ -731,32 +791,22 @@ LUA_API int lua_setmetatable (lua_State *L, int objindex) {
 }
 
 
-LUA_API int lua_setfenv (lua_State *L, int idx) {
+LUA_API void lua_setuservalue (lua_State *L, int idx) {
   StkId o;
-  int res = 1;
   lua_lock(L);
   api_checknelems(L, 1);
-  o = index2adr(L, idx);
+  o = index2addr(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;
+  api_check(L, ttisuserdata(o), "userdata expected");
+  if (ttisnil(L->top - 1))
+    uvalue(o)->env = NULL;
+  else {
+    api_check(L, ttistable(L->top - 1), "table expected");
+    uvalue(o)->env = hvalue(L->top - 1);
+    luaC_objbarrier(L, gcvalue(o), hvalue(L->top - 1));
   }
-  if (res) luaC_objbarrier(L, gcvalue(o), hvalue(L->top - 1));
   L->top--;
   lua_unlock(L);
-  return res;
 }
 
 
@@ -765,21 +815,37 @@ LUA_API int lua_setfenv (lua_State *L, int idx) {
 */
 
 
-#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)), \
+	"results from function overflow current stack size")
 
 
-#define checkresults(L,na,nr) \
-     api_check(L, (nr) == LUA_MULTRET || (L->ci->top - L->top >= (nr) - (na)))
-	
+LUA_API int lua_getctx (lua_State *L, int *ctx) {
+  if (L->ci->callstatus & CIST_YIELDED) {
+    if (ctx) *ctx = L->ci->u.c.ctx;
+    return L->ci->u.c.status;
+  }
+  else return LUA_OK;
+}
+
 
-LUA_API void lua_call (lua_State *L, int nargs, int nresults) {
+LUA_API void lua_callk (lua_State *L, int nargs, int nresults, int ctx,
+                        lua_CFunction k) {
   StkId func;
   lua_lock(L);
+  api_check(L, k == NULL || !isLua(L->ci),
+    "cannot use continuations inside hooks");
   api_checknelems(L, nargs+1);
+  api_check(L, L->status == LUA_OK, "cannot do calls on non-normal thread");
   checkresults(L, nargs, nresults);
   func = L->top - (nargs+1);
-  luaD_call(L, func, nresults);
+  if (k != NULL && L->nny == 0) {  /* need to prepare continuation? */
+    L->ci->u.c.k = k;  /* save continuation */
+    L->ci->u.c.ctx = ctx;  /* save context */
+    luaD_call(L, func, nresults, 1);  /* do the call */
+  }
+  else  /* no continuation or no yieldable */
+    luaD_call(L, func, nresults, 0);  /* just do the call */
   adjustresults(L, nresults);
   lua_unlock(L);
 }
@@ -797,68 +863,56 @@ struct CallS {  /* data to `f_call' */
 
 static void f_call (lua_State *L, void *ud) {
   struct CallS *c = cast(struct CallS *, ud);
-  luaD_call(L, c->func, c->nresults);
+  luaD_call(L, c->func, c->nresults, 0);
 }
 
 
 
-LUA_API int lua_pcall (lua_State *L, int nargs, int nresults, int errfunc) {
+LUA_API int lua_pcallk (lua_State *L, int nargs, int nresults, int errfunc,
+                        int ctx, lua_CFunction k) {
   struct CallS c;
   int status;
   ptrdiff_t func;
   lua_lock(L);
+  api_check(L, k == NULL || !isLua(L->ci),
+    "cannot use continuations inside hooks");
   api_checknelems(L, nargs+1);
+  api_check(L, L->status == LUA_OK, "cannot do calls on non-normal thread");
   checkresults(L, nargs, nresults);
   if (errfunc == 0)
     func = 0;
   else {
-    StkId o = index2adr(L, errfunc);
+    StkId o = index2addr(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);
+  if (k == NULL || L->nny > 0) {  /* no continuation or no yieldable? */
+    c.nresults = nresults;  /* do a 'conventional' protected call */
+    status = luaD_pcall(L, f_call, &c, savestack(L, c.func), func);
+  }
+  else {  /* prepare continuation (call is already protected by 'resume') */
+    CallInfo *ci = L->ci;
+    ci->u.c.k = k;  /* save continuation */
+    ci->u.c.ctx = ctx;  /* save context */
+    /* save information for error recovery */
+    ci->u.c.extra = savestack(L, c.func);
+    ci->u.c.old_allowhook = L->allowhook;
+    ci->u.c.old_errfunc = L->errfunc;
+    L->errfunc = func;
+    /* mark that function may do error recovery */
+    ci->callstatus |= CIST_YPCALL;
+    luaD_call(L, c.func, nresults, 1);  /* do the call */
+    ci->callstatus &= ~CIST_YPCALL;
+    L->errfunc = ci->u.c.old_errfunc;
+    status = LUA_OK;  /* if it is here, there were no errors */
+  }
   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;
@@ -867,6 +921,17 @@ LUA_API int lua_load (lua_State *L, lua_Reader reader, void *data,
   if (!chunkname) chunkname = "?";
   luaZ_init(L, &z, reader, data);
   status = luaD_protectedparser(L, &z, chunkname);
+  if (status == LUA_OK) {  /* no errors? */
+    LClosure *f = clLvalue(L->top - 1);  /* get newly created function */
+    if (f->nupvalues == 1) {  /* does it have one upvalue? */
+      /* get global table from registry */
+      Table *reg = hvalue(&G(L)->l_registry);
+      const TValue *gt = luaH_getint(reg, LUA_RIDX_GLOBALS);
+      /* set global table as 1st upvalue of 'f' (may be LUA_ENV) */
+      setobj(L, f->upvals[0]->v, gt);
+      luaC_barrier(L, f->upvals[0], gt);
+    }
+  }
   lua_unlock(L);
   return status;
 }
@@ -879,7 +944,7 @@ LUA_API int lua_dump (lua_State *L, lua_Writer writer, void *data) {
   api_checknelems(L, 1);
   o = L->top - 1;
   if (isLfunction(o))
-    status = luaU_dump(L, clvalue(o)->l.p, writer, data, 0);
+    status = luaU_dump(L, getproto(o), writer, data, 0);
   else
     status = 1;
   lua_unlock(L);
@@ -903,37 +968,39 @@ LUA_API int lua_gc (lua_State *L, int what, int data) {
   g = G(L);
   switch (what) {
     case LUA_GCSTOP: {
-      g->GCthreshold = MAX_LUMEM;
+      g->gcrunning = 0;
       break;
     }
     case LUA_GCRESTART: {
-      g->GCthreshold = g->totalbytes;
+      luaE_setdebt(g, 0);
+      g->gcrunning = 1;
       break;
     }
     case LUA_GCCOLLECT: {
-      luaC_fullgc(L);
+      luaC_fullgc(L, 0);
       break;
     }
     case LUA_GCCOUNT: {
       /* GC values are expressed in Kbytes: #bytes/2^10 */
-      res = cast_int(g->totalbytes >> 10);
+      res = cast_int(gettotalbytes(g) >> 10);
       break;
     }
     case LUA_GCCOUNTB: {
-      res = cast_int(g->totalbytes & 0x3ff);
+      res = cast_int(gettotalbytes(g) & 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;
+      if (g->gckind == KGC_GEN) {  /* generational mode? */
+        res = (g->lastmajormem == 0);  /* 1 if will do major collection */
+        luaC_forcestep(L);  /* do a single step */
+      }
+      else {
+        while (data-- >= 0) {
+          luaC_forcestep(L);
+          if (g->gcstate == GCSpause) {  /* end of cycle? */
+            res = 1;  /* signal it */
+            break;
+          }
         }
       }
       break;
@@ -943,11 +1010,28 @@ LUA_API int lua_gc (lua_State *L, int what, int data) {
       g->gcpause = data;
       break;
     }
+    case LUA_GCSETMAJORINC: {
+      res = g->gcmajorinc;
+      g->gcmajorinc = data;
+      break;
+    }
     case LUA_GCSETSTEPMUL: {
       res = g->gcstepmul;
       g->gcstepmul = data;
       break;
     }
+    case LUA_GCISRUNNING: {
+      res = g->gcrunning;
+      break;
+    }
+    case LUA_GCGEN: {  /* change collector to generational mode */
+      luaC_changemode(L, KGC_GEN);
+      break;
+    }
+    case LUA_GCINC: {  /* change collector to incremental mode */
+      luaC_changemode(L, KGC_NORMAL);
+      break;
+    }
     default: res = -1;  /* invalid option */
   }
   lua_unlock(L);
@@ -974,8 +1058,8 @@ 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));
+  t = index2addr(L, idx);
+  api_check(L, ttistable(t), "table expected");
   more = luaH_next(L, hvalue(t), L->top - 1);
   if (more) {
     api_incr_top(L);
@@ -992,8 +1076,7 @@ LUA_API void lua_concat (lua_State *L, int n) {
   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);
+    luaV_concat(L, n);
   }
   else if (n == 0) {  /* push empty string */
     setsvalue2s(L, L->top, luaS_newlstr(L, "", 0));
@@ -1004,6 +1087,16 @@ LUA_API void lua_concat (lua_State *L, int n) {
 }
 
 
+LUA_API void lua_len (lua_State *L, int idx) {
+  StkId t;
+  lua_lock(L);
+  t = index2addr(L, idx);
+  luaV_objlen(L, L->top, t);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
 LUA_API lua_Alloc lua_getallocf (lua_State *L, void **ud) {
   lua_Alloc f;
   lua_lock(L);
@@ -1026,7 +1119,7 @@ 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));
+  u = luaS_newudata(L, size, NULL);
   setuvalue(L, L->top, u);
   api_incr_top(L);
   lua_unlock(L);
@@ -1036,20 +1129,29 @@ LUA_API void *lua_newuserdata (lua_State *L, size_t size) {
 
 
 
-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]);
+static const char *aux_upvalue (StkId fi, int n, TValue **val,
+                                GCObject **owner) {
+  switch (ttype(fi)) {
+    case LUA_TCCL: {  /* C closure */
+      CClosure *f = clCvalue(fi);
+      if (!(1 <= n && n <= f->nupvalues)) return NULL;
+      *val = &f->upvalue[n-1];
+      if (owner) *owner = obj2gco(f);
+      return "";
+    }
+    case LUA_TLCL: {  /* Lua closure */
+      LClosure *f = clLvalue(fi);
+      const char *name;
+      Proto *p = f->p;
+      if (!(1 <= n && n <= p->sizeupvalues)) return NULL;
+      *val = f->upvals[n-1]->v;
+      if (owner) *owner = obj2gco(f->upvals[n - 1]);
+      name = getstr(p->upvalues[n-1].name);
+      if (name == NULL)  /* no debug information? */
+        name = "";
+      return name;
+    }
+    default: return NULL;  /* not a closure */
   }
 }
 
@@ -1058,7 +1160,7 @@ 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);
+  name = aux_upvalue(index2addr(L, funcindex), n, &val, NULL);
   if (name) {
     setobj2s(L, L->top, val);
     api_incr_top(L);
@@ -1071,17 +1173,58 @@ LUA_API const char *lua_getupvalue (lua_State *L, int funcindex, int n) {
 LUA_API const char *lua_setupvalue (lua_State *L, int funcindex, int n) {
   const char *name;
   TValue *val;
+  GCObject *owner;
   StkId fi;
   lua_lock(L);
-  fi = index2adr(L, funcindex);
+  fi = index2addr(L, funcindex);
   api_checknelems(L, 1);
-  name = aux_upvalue(fi, n, &val);
+  name = aux_upvalue(fi, n, &val, &owner);
   if (name) {
     L->top--;
     setobj(L, val, L->top);
-    luaC_barrier(L, clvalue(fi), L->top);
+    luaC_barrier(L, owner, L->top);
   }
   lua_unlock(L);
   return name;
 }
 
+
+static UpVal **getupvalref (lua_State *L, int fidx, int n, LClosure **pf) {
+  LClosure *f;
+  StkId fi = index2addr(L, fidx);
+  api_check(L, ttisLclosure(fi), "Lua function expected");
+  f = clLvalue(fi);
+  api_check(L, (1 <= n && n <= f->p->sizeupvalues), "invalid upvalue index");
+  if (pf) *pf = f;
+  return &f->upvals[n - 1];  /* get its upvalue pointer */
+}
+
+
+LUA_API void *lua_upvalueid (lua_State *L, int fidx, int n) {
+  StkId fi = index2addr(L, fidx);
+  switch (ttype(fi)) {
+    case LUA_TLCL: {  /* lua closure */
+      return *getupvalref(L, fidx, n, NULL);
+    }
+    case LUA_TCCL: {  /* C closure */
+      CClosure *f = clCvalue(fi);
+      api_check(L, 1 <= n && n <= f->nupvalues, "invalid upvalue index");
+      return &f->upvalue[n - 1];
+    }
+    default: {
+      api_check(L, 0, "closure expected");
+      return NULL;
+    }
+  }
+}
+
+
+LUA_API void lua_upvaluejoin (lua_State *L, int fidx1, int n1,
+                                            int fidx2, int n2) {
+  LClosure *f1;
+  UpVal **up1 = getupvalref(L, fidx1, n1, &f1);
+  UpVal **up2 = getupvalref(L, fidx2, n2, NULL);
+  *up1 = *up2;
+  luaC_objbarrier(L, f1, *up2);
+}
+
diff --git a/src/lapi.h b/src/lapi.h
index 2c3fab2..0909a39 100644..100755
--- a/src/lapi.h
+++ b/src/lapi.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lapi.h,v 2.2.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lapi.h,v 2.7 2009/11/27 15:37:59 roberto Exp $
 ** Auxiliary functions from Lua API
 ** See Copyright Notice in lua.h
 */
@@ -8,9 +8,17 @@
 #define lapi_h
 
 
-#include "lobject.h"
+#include "llimits.h"
+#include "lstate.h"
 
+#define api_incr_top(L)   {L->top++; api_check(L, L->top <= L->ci->top, \
+				"stack overflow");}
+
+#define adjustresults(L,nres) \
+    { if ((nres) == LUA_MULTRET && L->ci->top < L->top) L->ci->top = L->top; }
+
+#define api_checknelems(L,n)	api_check(L, (n) < (L->top - L->ci->func), \
+				  "not enough elements in the stack")
 
-LUAI_FUNC void luaA_pushobject (lua_State *L, const TValue *o);
 
 #endif
diff --git a/src/lauxlib.c b/src/lauxlib.c
index 10f14e2..b765cfd 100644..100755
--- a/src/lauxlib.c
+++ b/src/lauxlib.c
@@ -1,11 +1,10 @@
 /*
-** $Id: lauxlib.c,v 1.159.1.3 2008/01/21 13:20:51 roberto Exp $
+** $Id: lauxlib.c,v 1.233 2011/06/16 14:11:04 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>
@@ -25,12 +24,125 @@
 #include "lauxlib.h"
 
 
-#define FREELIST_REF	0	/* free list of references */
+/*
+** {======================================================
+** Traceback
+** =======================================================
+*/
+
+
+#define LEVELS1	12	/* size of the first part of the stack */
+#define LEVELS2	10	/* size of the second part of the stack */
+
+
+
+/*
+** search for 'objidx' in table at index -1.
+** return 1 + string at top if find a good name.
+*/
+static int findfield (lua_State *L, int objidx, int level) {
+  int found = 0;
+  if (level == 0 || !lua_istable(L, -1))
+    return 0;  /* not found */
+  lua_pushnil(L);  /* start 'next' loop */
+  while (!found && lua_next(L, -2)) {  /* for each pair in table */
+    if (lua_type(L, -2) == LUA_TSTRING) {  /* ignore non-string keys */
+      if (lua_rawequal(L, objidx, -1)) {  /* found object? */
+        lua_pop(L, 1);  /* remove value (but keep name) */
+        return 1;
+      }
+      else if (findfield(L, objidx, level - 1)) {  /* try recursively */
+        lua_remove(L, -2);  /* remove table (but keep name) */
+        lua_pushliteral(L, ".");
+        lua_insert(L, -2);  /* place '.' between the two names */
+        lua_concat(L, 3);
+        return 1;
+      }
+    }
+    lua_pop(L, 1);  /* remove value */
+  }
+  return 0;  /* not found */
+}
+
+
+static int pushglobalfuncname (lua_State *L, lua_Debug *ar) {
+  int top = lua_gettop(L);
+  lua_getinfo(L, "f", ar);  /* push function */
+  lua_pushglobaltable(L);
+  if (findfield(L, top + 1, 2)) {
+    lua_copy(L, -1, top + 1);  /* move name to proper place */
+    lua_pop(L, 2);  /* remove pushed values */
+    return 1;
+  }
+  else {
+    lua_settop(L, top);  /* remove function and global table */
+    return 0;
+  }
+}
+
 
+static void pushfuncname (lua_State *L, lua_Debug *ar) {
+  if (*ar->namewhat != '\0')  /* is there a name? */
+    lua_pushfstring(L, "function " LUA_QS, ar->name);
+  else if (*ar->what == 'm')  /* main? */
+      lua_pushfstring(L, "main chunk");
+  else if (*ar->what == 'C' || *ar->what == 't') {
+    if (pushglobalfuncname(L, ar)) {
+      lua_pushfstring(L, "function " LUA_QS, lua_tostring(L, -1));
+      lua_remove(L, -2);  /* remove name */
+    }
+    else
+      lua_pushliteral(L, "?");
+  }
+  else
+    lua_pushfstring(L, "function <%s:%d>", ar->short_src, ar->linedefined);
+}
 
-/* convert a stack index to positive */
-#define abs_index(L, i)		((i) > 0 || (i) <= LUA_REGISTRYINDEX ? (i) : \
-					lua_gettop(L) + (i) + 1)
+
+static int countlevels (lua_State *L) {
+  lua_Debug ar;
+  int li = 1, le = 1;
+  /* find an upper bound */
+  while (lua_getstack(L, le, &ar)) { li = le; le *= 2; }
+  /* do a binary search */
+  while (li < le) {
+    int m = (li + le)/2;
+    if (lua_getstack(L, m, &ar)) li = m + 1;
+    else le = m;
+  }
+  return le - 1;
+}
+
+
+LUALIB_API void luaL_traceback (lua_State *L, lua_State *L1,
+                                const char *msg, int level) {
+  lua_Debug ar;
+  int top = lua_gettop(L);
+  int numlevels = countlevels(L1);
+  int mark = (numlevels > LEVELS1 + LEVELS2) ? LEVELS1 : 0;
+  if (msg) lua_pushfstring(L, "%s\n", msg);
+  lua_pushliteral(L, "stack traceback:");
+  while (lua_getstack(L1, level++, &ar)) {
+    if (level == mark) {  /* too many levels? */
+      lua_pushliteral(L, "\n\t...");  /* add a '...' */
+      level = numlevels - LEVELS2;  /* and skip to last ones */
+    }
+    else {
+      lua_getinfo(L1, "Slnt", &ar);
+      lua_pushfstring(L, "\n\t%s:", ar.short_src);
+      if (ar.currentline > 0)
+        lua_pushfstring(L, "%d:", ar.currentline);
+      lua_pushliteral(L, " in ");
+      pushfuncname(L, &ar);
+      if (ar.istailcall)
+        lua_pushliteral(L, "\n\t(...tail calls...)");
+      lua_concat(L, lua_gettop(L) - top);
+    }
+  }
+  lua_concat(L, lua_gettop(L) - top);
+}
+
+/* }====================================================== */
 
 
 /*
@@ -39,7 +151,6 @@
 ** =======================================================
 */
 
-
 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? */
@@ -48,17 +159,16 @@ LUALIB_API int luaL_argerror (lua_State *L, int narg, const char *extramsg) {
   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);
+      return luaL_error(L, "calling " LUA_QS " on bad self", ar.name);
   }
   if (ar.name == NULL)
-    ar.name = "?";
+    ar.name = (pushglobalfuncname(L, &ar)) ? lua_tostring(L, -1) : "?";
   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) {
+static int typeerror (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);
@@ -66,7 +176,7 @@ LUALIB_API int luaL_typerror (lua_State *L, int narg, const char *tname) {
 
 
 static void tag_error (lua_State *L, int narg, int tag) {
-  luaL_typerror(L, narg, lua_typename(L, tag));
+  typeerror(L, narg, lua_typename(L, tag));
 }
 
 
@@ -93,21 +203,71 @@ LUALIB_API int luaL_error (lua_State *L, const char *fmt, ...) {
   return lua_error(L);
 }
 
-/* }====================================================== */
 
+LUALIB_API int luaL_fileresult (lua_State *L, int stat, const char *fname) {
+  int en = errno;  /* calls to Lua API may change this value */
+  if (stat) {
+    lua_pushboolean(L, 1);
+    return 1;
+  }
+  else {
+    lua_pushnil(L);
+    if (fname)
+      lua_pushfstring(L, "%s: %s", fname, strerror(en));
+    else
+      lua_pushfstring(L, "%s", strerror(en));
+    lua_pushinteger(L, en);
+    return 3;
+  }
+}
 
-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));
+
+#if !defined(inspectstat)	/* { */
+
+#if defined(LUA_USE_POSIX)
+
+#include <sys/wait.h>
+
+/*
+** use appropriate macros to interpret 'pclose' return status
+*/
+#define inspectstat(stat,what)  \
+   if (WIFEXITED(stat)) { stat = WEXITSTATUS(stat); } \
+   else if (WIFSIGNALED(stat)) { stat = WTERMSIG(stat); what = "signal"; }
+
+#else
+
+#define inspectstat(stat,what)  /* no op */
+
+#endif
+
+#endif				/* } */
+
+
+LUALIB_API int luaL_execresult (lua_State *L, int stat) {
+  const char *what = "exit";  /* type of termination */
+  if (stat == -1)  /* error? */
+    return luaL_fileresult(L, 0, NULL);
+  else {
+    inspectstat(stat, what);  /* interpret result */
+    if (*what == 'e' && stat == 0)  /* successful termination? */
+      lua_pushboolean(L, 1);
+    else
+      lua_pushnil(L);
+    lua_pushstring(L, what);
+    lua_pushinteger(L, stat);
+    return 3;  /* return true/nil,what,code */
+  }
 }
 
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Userdata's metatable manipulation
+** =======================================================
+*/
 
 LUALIB_API int luaL_newmetatable (lua_State *L, const char *tname) {
   lua_getfield(L, LUA_REGISTRYINDEX, tname);  /* get registry.name */
@@ -121,25 +281,62 @@ 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_setmetatable (lua_State *L, const char *tname) {
+  luaL_getmetatable(L, tname);
+  lua_setmetatable(L, -2);
+}
+
+
+LUALIB_API void *luaL_testudata (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;
-      }
+      if (!lua_rawequal(L, -1, -2))  /* not the same? */
+        p = NULL;  /* value is a userdata with wrong metatable */
+      lua_pop(L, 2);  /* remove both metatables */
+      return p;
     }
   }
-  luaL_typerror(L, ud, tname);  /* else error */
-  return NULL;  /* to avoid warnings */
+  return NULL;  /* value is not a userdata with a metatable */
+}
+
+
+LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) {
+  void *p = luaL_testudata(L, ud, tname);
+  if (p == NULL) typeerror(L, ud, tname);
+  return p;
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Argument check functions
+** =======================================================
+*/
+
+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 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_checkstack (lua_State *L, int space, const char *msg) {
+  if (!lua_checkstack(L, space)) {
+    if (msg)
+      luaL_error(L, "stack overflow (%s)", msg);
+    else
+      luaL_error(L, "stack overflow");
+  }
 }
 
 
@@ -174,8 +371,9 @@ LUALIB_API const char *luaL_optlstring (lua_State *L, int narg,
 
 
 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 */
+  int isnum;
+  lua_Number d = lua_tonumberx(L, narg, &isnum);
+  if (!isnum)
     tag_error(L, narg, LUA_TNUMBER);
   return d;
 }
@@ -187,255 +385,79 @@ LUALIB_API lua_Number luaL_optnumber (lua_State *L, int narg, lua_Number 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 */
+  int isnum;
+  lua_Integer d = lua_tointegerx(L, narg, &isnum);
+  if (!isnum)
     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 lua_Unsigned luaL_checkunsigned (lua_State *L, int narg) {
+  int isnum;
+  lua_Unsigned d = lua_tounsignedx(L, narg, &isnum);
+  if (!isnum)
+    tag_error(L, narg, LUA_TNUMBER);
+  return d;
 }
 
 
-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 lua_Integer luaL_optinteger (lua_State *L, int narg,
+                                                      lua_Integer def) {
+  return luaL_opt(L, luaL_checkinteger, narg, def);
 }
 
 
-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);
+LUALIB_API lua_Unsigned luaL_optunsigned (lua_State *L, int narg,
+                                                        lua_Unsigned def) {
+  return luaL_opt(L, luaL_checkunsigned, narg, def);
 }
 
-#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;
-  }
-}
+/*
+** check whether buffer is using a userdata on the stack as a temporary
+** buffer
+*/
+#define buffonstack(B)	((B)->b != (B)->initb)
 
 
-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;
+/*
+** returns a pointer to a free area with at least 'sz' bytes
+*/
+LUALIB_API char *luaL_prepbuffsize (luaL_Buffer *B, size_t sz) {
+  lua_State *L = B->L;
+  if (B->size - B->n < sz) {  /* not enough space? */
+    char *newbuff;
+    size_t newsize = B->size * 2;  /* double buffer size */
+    if (newsize - B->n < sz)  /* not bit enough? */
+      newsize = B->n + sz;
+    if (newsize < B->n || newsize - B->n < sz)
+      luaL_error(L, "buffer too large");
+    /* create larger buffer */
+    newbuff = (char *)lua_newuserdata(L, newsize * sizeof(char));
+    /* move content to new buffer */
+    memcpy(newbuff, B->b, B->n * sizeof(char));
+    if (buffonstack(B))
+      lua_remove(L, -2);  /* remove old buffer */
+    B->b = newbuff;
+    B->size = newsize;
   }
-}
-
-
-LUALIB_API char *luaL_prepbuffer (luaL_Buffer *B) {
-  if (emptybuffer(B))
-    adjuststack(B);
-  return B->buffer;
+  return &B->b[B->n];
 }
 
 
 LUALIB_API void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l) {
-  while (l--)
-    luaL_addchar(B, *s++);
+  char *b = luaL_prepbuffsize(B, l);
+  memcpy(b, s, l * sizeof(char));
+  luaL_addsize(B, l);
 }
 
 
@@ -445,57 +467,72 @@ LUALIB_API void luaL_addstring (luaL_Buffer *B, const char *s) {
 
 
 LUALIB_API void luaL_pushresult (luaL_Buffer *B) {
-  emptybuffer(B);
-  lua_concat(B->L, B->lvl);
-  B->lvl = 1;
+  lua_State *L = B->L;
+  lua_pushlstring(L, B->b, B->n);
+  if (buffonstack(B))
+    lua_remove(L, -2);  /* remove old buffer */
+}
+
+
+LUALIB_API void luaL_pushresultsize (luaL_Buffer *B, size_t sz) {
+  luaL_addsize(B, sz);
+  luaL_pushresult(B);
 }
 
 
 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);
-  }
+  size_t l;
+  const char *s = lua_tolstring(L, -1, &l);
+  if (buffonstack(B))
+    lua_insert(L, -2);  /* put value below buffer */
+  luaL_addlstring(B, s, l);
+  lua_remove(L, (buffonstack(B)) ? -2 : -1);  /* remove value */
 }
 
 
 LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) {
   B->L = L;
-  B->p = B->buffer;
-  B->lvl = 0;
+  B->b = B->initb;
+  B->n = 0;
+  B->size = LUAL_BUFFERSIZE;
+}
+
+
+LUALIB_API char *luaL_buffinitsize (lua_State *L, luaL_Buffer *B, size_t sz) {
+  luaL_buffinit(L, B);
+  return luaL_prepbuffsize(B, sz);
 }
 
 /* }====================================================== */
 
 
+/*
+** {======================================================
+** Reference system
+** =======================================================
+*/
+
+/* index of free-list header */
+#define freelist	0
+
+
 LUALIB_API int luaL_ref (lua_State *L, int t) {
   int ref;
-  t = abs_index(L, t);
+  t = lua_absindex(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_rawgeti(L, t, freelist);  /* get first free element */
+  ref = (int)lua_tointeger(L, -1);  /* ref = t[freelist] */
   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, freelist);  /* (t[freelist] = t[ref]) */
   }
+  else  /* no free elements */
+    ref = (int)lua_rawlen(L, t) + 1;  /* get a new reference */
   lua_rawseti(L, t, ref);
   return ref;
 }
@@ -503,14 +540,15 @@ LUALIB_API int luaL_ref (lua_State *L, int t) {
 
 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] */
+    t = lua_absindex(L, t);
+    lua_rawgeti(L, t, freelist);
+    lua_rawseti(L, t, ref);  /* t[ref] = t[freelist] */
     lua_pushinteger(L, ref);
-    lua_rawseti(L, t, FREELIST_REF);  /* t[FREELIST_REF] = ref */
+    lua_rawseti(L, t, freelist);  /* t[freelist] = ref */
   }
 }
 
+/* }====================================================== */
 
 
 /*
@@ -520,23 +558,27 @@ LUALIB_API void luaL_unref (lua_State *L, int t, int ref) {
 */
 
 typedef struct LoadF {
-  int extraline;
-  FILE *f;
-  char buff[LUAL_BUFFERSIZE];
+  int n;  /* number of pre-read characters */
+  FILE *f;  /* file being read */
+  char buff[LUAL_BUFFERSIZE];  /* area for reading file */
 } 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 (lf->n > 0) {  /* are there pre-read characters to be read? */
+    *size = lf->n;  /* return them (chars already in buffer) */
+    lf->n = 0;  /* no more pre-read characters */
   }
-  if (feof(lf->f)) return NULL;
-  *size = fread(lf->buff, 1, sizeof(lf->buff), lf->f);
-  return (*size > 0) ? lf->buff : NULL;
+  else {  /* read a block from file */
+    /* 'fread' can return > 0 *and* set the EOF flag. If next call to
+       'getF' called 'fread', it might still wait for user input.
+       The next check avoids this problem. */
+    if (feof(lf->f)) return NULL;
+    *size = fread(lf->buff, 1, sizeof(lf->buff), lf->f);  /* read block */
+  }
+  return lf->buff;
 }
 
 
@@ -549,12 +591,43 @@ static int errfile (lua_State *L, const char *what, int fnameindex) {
 }
 
 
+static int skipBOM (LoadF *lf) {
+  const char *p = "\xEF\xBB\xBF";  /* Utf8 BOM mark */
+  int c;
+  lf->n = 0;
+  do {
+    c = getc(lf->f);
+    if (c == EOF || c != *(unsigned char *)p++) return c;
+    lf->buff[lf->n++] = c;  /* to be read by the parser */
+  } while (*p != '\0');
+  lf->n = 0;  /* prefix matched; discard it */
+  return getc(lf->f);  /* return next character */
+}
+
+
+/*
+** reads the first character of file 'f' and skips an optional BOM mark
+** in its beginning plus its first line if it starts with '#'. Returns
+** true if it skipped the first line.  In any case, '*cp' has the
+** first "valid" character of the file (after the optional BOM and
+** a first-line comment).
+*/
+static int skipcomment (LoadF *lf, int *cp) {
+  int c = *cp = skipBOM(lf);
+  if (c == '#') {  /* first line is a comment (Unix exec. file)? */
+    while ((c = getc(lf->f)) != EOF && c != '\n') ;  /* skip first line */
+    *cp = getc(lf->f);  /* skip end-of-line */
+    return 1;  /* there was a comment */
+  }
+  else return 0;  /* no comment */
+}
+
+
 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;
@@ -564,20 +637,15 @@ LUALIB_API int luaL_loadfile (lua_State *L, const char *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 (skipcomment(&lf, &c))  /* read initial portion */
+    lf.buff[lf.n++] = '\n';  /* add line to correct line numbers */
   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;
+    skipcomment(&lf, &c);  /* re-read initial portion */
   }
-  ungetc(c, lf.f);
+  if (c != EOF)
+    lf.buff[lf.n++] = c;  /* 'c' is the first character of the stream */
   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) */
@@ -615,14 +683,234 @@ LUALIB_API int luaL_loadbuffer (lua_State *L, const char *buff, size_t size,
 }
 
 
-LUALIB_API int (luaL_loadstring) (lua_State *L, const char *s) {
+LUALIB_API int luaL_loadstring (lua_State *L, const char *s) {
   return luaL_loadbuffer(L, s, strlen(s), s);
 }
 
+/* }====================================================== */
+
+
+
+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 = lua_absindex(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 int luaL_len (lua_State *L, int idx) {
+  int l;
+  int isnum;
+  lua_len(L, idx);
+  l = (int)lua_tointegerx(L, -1, &isnum);
+  if (!isnum)
+    luaL_error(L, "object length is not a number");
+  lua_pop(L, 1);  /* remove object */
+  return l;
+}
+
+
+LUALIB_API const char *luaL_tolstring (lua_State *L, int idx, size_t *len) {
+  if (!luaL_callmeta(L, idx, "__tostring")) {  /* no metafield? */
+    switch (lua_type(L, idx)) {
+      case LUA_TNUMBER:
+      case LUA_TSTRING:
+        lua_pushvalue(L, idx);
+        break;
+      case LUA_TBOOLEAN:
+        lua_pushstring(L, (lua_toboolean(L, idx) ? "true" : "false"));
+        break;
+      case LUA_TNIL:
+        lua_pushliteral(L, "nil");
+        break;
+      default:
+        lua_pushfstring(L, "%s: %p", luaL_typename(L, idx),
+                                            lua_topointer(L, idx));
+        break;
+    }
+  }
+  return lua_tolstring(L, -1, len);
+}
+
+
+/*
+** {======================================================
+** Compatibility with 5.1 module functions
+** =======================================================
+*/
+#if defined(LUA_COMPAT_MODULE)
+
+static const char *luaL_findtable (lua_State *L, int idx,
+                                   const char *fname, int szhint) {
+  const char *e;
+  if (idx) 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;
+}
+
+
+/*
+** Count number of elements in a luaL_Reg list.
+*/
+static int libsize (const luaL_Reg *l) {
+  int size = 0;
+  for (; l && l->name; l++) size++;
+  return size;
+}
+
+
+/*
+** Find or create a module table with a given name. The function
+** first looks at the _LOADED table and, if that fails, try a
+** global variable with that name. In any case, leaves on the stack
+** the module table.
+*/
+LUALIB_API void luaL_pushmodule (lua_State *L, const char *modname,
+                                 int sizehint) {
+  luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 1);  /* get _LOADED table */
+  lua_getfield(L, -1, modname);  /* get _LOADED[modname] */
+  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) */
+    lua_pushglobaltable(L);
+    if (luaL_findtable(L, 0, modname, sizehint) != NULL)
+      luaL_error(L, "name conflict for module " LUA_QS, modname);
+    lua_pushvalue(L, -1);
+    lua_setfield(L, -3, modname);  /* _LOADED[modname] = new table */
+  }
+  lua_remove(L, -2);  /* remove _LOADED table */
+}
+
 
+LUALIB_API void luaL_openlib (lua_State *L, const char *libname,
+                               const luaL_Reg *l, int nup) {
+  luaL_checkversion(L);
+  if (libname) {
+    luaL_pushmodule(L, libname, libsize(l));  /* get/create library table */
+    lua_insert(L, -(nup + 1));  /* move library table to below upvalues */
+  }
+  if (l)
+    luaL_setfuncs(L, l, nup);
+  else
+    lua_pop(L, nup);  /* remove upvalues */
+}
 
+#endif
 /* }====================================================== */
 
+/*
+** set functions from list 'l' into table at top - 'nup'; each
+** function gets the 'nup' elements at the top as upvalues.
+** Returns with only the table at the stack.
+*/
+LUALIB_API void luaL_setfuncs (lua_State *L, const luaL_Reg *l, int nup) {
+  luaL_checkstack(L, nup, "too many upvalues");
+  for (; l->name != NULL; l++) {  /* fill the table with given functions */
+    int i;
+    for (i = 0; i < nup; i++)  /* copy upvalues to the top */
+      lua_pushvalue(L, -nup);
+    lua_pushcclosure(L, l->func, nup);  /* closure with those upvalues */
+    lua_setfield(L, -(nup + 2), l->name);
+  }
+  lua_pop(L, nup);  /* remove upvalues */
+}
+
+
+/*
+** ensure that stack[idx][fname] has a table and push that table
+** into the stack
+*/
+LUALIB_API int luaL_getsubtable (lua_State *L, int idx, const char *fname) {
+  lua_getfield(L, idx, fname);
+  if (lua_istable(L, -1)) return 1;  /* table already there */
+  else {
+    idx = lua_absindex(L, idx);
+    lua_pop(L, 1);  /* remove previous result */
+    lua_newtable(L);
+    lua_pushvalue(L, -1);  /* copy to be left at top */
+    lua_setfield(L, idx, fname);  /* assign new table to field */
+    return 0;  /* false, because did not find table there */
+  }
+}
+
+
+/*
+** stripped-down 'require'. Calls 'openf' to open a module,
+** registers the result in 'package.loaded' table and, if 'glb'
+** is true, also registers the result in the global table.
+** Leaves resulting module on the top.
+*/
+LUALIB_API void luaL_requiref (lua_State *L, const char *modname,
+                               lua_CFunction openf, int glb) {
+  lua_pushcfunction(L, openf);
+  lua_pushstring(L, modname);  /* argument to open function */
+  lua_call(L, 1, 1);  /* open module */
+  luaL_getsubtable(L, LUA_REGISTRYINDEX, "_LOADED");
+  lua_pushvalue(L, -2);  /* make copy of module (call result) */
+  lua_setfield(L, -2, modname);  /* _LOADED[modname] = module */
+  lua_pop(L, 1);  /* remove _LOADED table */
+  if (glb) {
+    lua_pushglobaltable(L);
+    lua_pushvalue(L, -2);  /* copy of 'mod' */
+    lua_setfield(L, -2, modname);  /* _G[modname] = module */
+    lua_pop(L, 1);  /* remove _G table */
+  }
+}
+
+
+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);
+}
+
 
 static void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize) {
   (void)ud;
@@ -637,10 +925,9 @@ static void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize) {
 
 
 static int panic (lua_State *L) {
-  (void)L;  /* to avoid warnings */
-  fprintf(stderr, "PANIC: unprotected error in call to Lua API (%s)\n",
+  luai_writestringerror("PANIC: unprotected error in call to Lua API (%s)\n",
                    lua_tostring(L, -1));
-  return 0;
+  return 0;  /* return to Lua to abort */
 }
 
 
@@ -650,3 +937,20 @@ LUALIB_API lua_State *luaL_newstate (void) {
   return L;
 }
 
+
+LUALIB_API void luaL_checkversion_ (lua_State *L, lua_Number ver) {
+  const lua_Number *v = lua_version(L);
+  if (v != lua_version(NULL))
+    luaL_error(L, "multiple Lua VMs detected");
+  else if (*v != ver)
+    luaL_error(L, "version mismatch: app. needs %d, Lua core provides %f",
+                  ver, *v);
+  /* check conversions number -> integer types */
+  lua_pushnumber(L, -(lua_Number)0x1234);
+  if (lua_tointeger(L, -1) != -0x1234 ||
+      lua_tounsigned(L, -1) != (lua_Unsigned)-0x1234)
+    luaL_error(L, "bad conversion number->int;"
+                  " must recompile Lua with proper settings");
+  lua_pop(L, 1);
+}
+
diff --git a/src/lauxlib.h b/src/lauxlib.h
index 3425823..a7aa0d7 100644..100755
--- a/src/lauxlib.h
+++ b/src/lauxlib.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lauxlib.h,v 1.88.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lauxlib.h,v 1.117 2011/06/16 14:10:12 roberto Exp $
 ** Auxiliary functions for building Lua libraries
 ** See Copyright Notice in lua.h
 */
@@ -15,18 +15,6 @@
 #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)
@@ -38,14 +26,12 @@ typedef struct luaL_Reg {
 } luaL_Reg;
 
 
+LUALIB_API void (luaL_checkversion_) (lua_State *L, lua_Number ver);
+#define luaL_checkversion(L)	luaL_checkversion_(L, LUA_VERSION_NUM)
 
-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 const char *(luaL_tolstring) (lua_State *L, int idx, size_t *len);
 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);
@@ -57,12 +43,17 @@ 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 lua_Unsigned (luaL_checkunsigned) (lua_State *L, int numArg);
+LUALIB_API lua_Unsigned (luaL_optunsigned) (lua_State *L, int numArg,
+                                            lua_Unsigned 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_setmetatable) (lua_State *L, const char *tname);
+LUALIB_API void *(luaL_testudata) (lua_State *L, int ud, 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);
@@ -71,6 +62,13 @@ 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_fileresult) (lua_State *L, int stat, const char *fname);
+LUALIB_API int (luaL_execresult) (lua_State *L, int stat);
+
+/* pre-defined references */
+#define LUA_NOREF       (-2)
+#define LUA_REFNIL      (-1)
+
 LUALIB_API int (luaL_ref) (lua_State *L, int t);
 LUALIB_API void (luaL_unref) (lua_State *L, int t, int ref);
 
@@ -81,15 +79,20 @@ LUALIB_API int (luaL_loadstring) (lua_State *L, const char *s);
 
 LUALIB_API lua_State *(luaL_newstate) (void);
 
+LUALIB_API int (luaL_len) (lua_State *L, int idx);
 
 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);
+LUALIB_API void (luaL_setfuncs) (lua_State *L, const luaL_Reg *l, int nup);
 
+LUALIB_API int (luaL_getsubtable) (lua_State *L, int idx, const char *fname);
 
+LUALIB_API void (luaL_traceback) (lua_State *L, lua_State *L1,
+                                  const char *msg, int level);
 
+LUALIB_API void (luaL_requiref) (lua_State *L, const char *modname,
+                                 lua_CFunction openf, int glb);
 
 /*
 ** ===============================================================
@@ -97,6 +100,12 @@ LUALIB_API const char *(luaL_findtable) (lua_State *L, int idx,
 ** ===============================================================
 */
 
+
+#define luaL_newlibtable(L,l)	\
+  lua_createtable(L, 0, sizeof(l)/sizeof((l)[0]) - 1)
+
+#define luaL_newlib(L,l)	(luaL_newlibtable(L,l), luaL_setfuncs(L,l,0))
+
 #define luaL_argcheck(L, cond,numarg,extramsg)	\
 		((void)((cond) || luaL_argerror(L, (numarg), (extramsg))))
 #define luaL_checkstring(L,n)	(luaL_checklstring(L, (n), NULL))
@@ -118,56 +127,54 @@ LUALIB_API const char *(luaL_findtable) (lua_State *L, int idx,
 
 #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) */
+  char *b;  /* buffer address */
+  size_t size;  /* buffer size */
+  size_t n;  /* number of characters in buffer */
   lua_State *L;
-  char buffer[LUAL_BUFFERSIZE];
+  char initb[LUAL_BUFFERSIZE];  /* initial buffer */
 } 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_addchar(B,c) \
+  ((void)((B)->n < (B)->size || luaL_prepbuffsize((B), 1)), \
+   ((B)->b[(B)->n++] = (c)))
 
-#define luaL_addsize(B,n)	((B)->p += (n))
+#define luaL_addsize(B,s)	((B)->n += (s))
 
 LUALIB_API void (luaL_buffinit) (lua_State *L, luaL_Buffer *B);
-LUALIB_API char *(luaL_prepbuffer) (luaL_Buffer *B);
+LUALIB_API char *(luaL_prepbuffsize) (luaL_Buffer *B, size_t sz);
 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);
+LUALIB_API void (luaL_pushresultsize) (luaL_Buffer *B, size_t sz);
+LUALIB_API char *(luaL_buffinitsize) (lua_State *L, luaL_Buffer *B, size_t sz);
 
+#define luaL_prepbuffer(B)	luaL_prepbuffsize(B, LUAL_BUFFERSIZE)
 
 /* }====================================================== */
 
 
-/* compatibility with ref system */
-
-/* pre-defined references */
-#define LUA_NOREF       (-2)
-#define LUA_REFNIL      (-1)
+/* compatibility with old module system */
+#if defined(LUA_COMPAT_MODULE)
 
-#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))
+LUALIB_API void (luaL_pushmodule) (lua_State *L, const char *modname,
+                                   int sizehint);
+LUALIB_API void (luaL_openlib) (lua_State *L, const char *libname,
+                                const luaL_Reg *l, int nup);
 
-#define lua_getref(L,ref)       lua_rawgeti(L, LUA_REGISTRYINDEX, (ref))
+#define luaL_register(L,n,l)	(luaL_openlib(L,(n),(l),0))
 
+#endif
 
-#define luaL_reg	luaL_Reg
 
 #endif
 
diff --git a/src/lbaselib.c b/src/lbaselib.c
index 2a4c079..e4daf5d 100644..100755
--- a/src/lbaselib.c
+++ b/src/lbaselib.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lbaselib.c,v 1.191.1.6 2008/02/14 16:46:22 roberto Exp $
+** $Id: lbaselib.c,v 1.264 2011/07/05 12:49:35 roberto Exp $
 ** Basic library
 ** See Copyright Notice in lua.h
 */
@@ -20,60 +20,66 @@
 #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;
+    size_t l;
     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 */
+    s = lua_tolstring(L, -1, &l);  /* 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);
+      return luaL_error(L,
+         LUA_QL("tostring") " must return a string to " LUA_QL("print"));
+    if (i>1) luai_writestring("\t", 1);
+    luai_writestring(s, l);
     lua_pop(L, 1);  /* pop result */
   }
-  fputs("\n", stdout);
+  luai_writeline();
   return 0;
 }
 
 
+#define SPACECHARS	" \f\n\r\t\v"
+
 static int luaB_tonumber (lua_State *L) {
   int base = luaL_optint(L, 2, 10);
+  luaL_argcheck(L, 2 <= base && base <= 36, 2, "base out of range");
   if (base == 10) {  /* standard conversion */
     luaL_checkany(L, 1);
     if (lua_isnumber(L, 1)) {
       lua_pushnumber(L, lua_tonumber(L, 1));
       return 1;
-    }
+    }  /* else not a number */
   }
   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);
+    size_t l;
+    const char *s = luaL_checklstring(L, 1, &l);
+    const char *e = s + l;  /* end point for 's' */
+    int neg = 0;
+    s += strspn(s, SPACECHARS);  /* skip initial spaces */
+    if (*s == '-') { s++; neg = 1; }  /* handle signal */
+    else if (*s == '+') s++;
+    if (isalnum((unsigned char)*s)) {
+      lua_Number n = 0;
+      do {
+        int digit = (isdigit((unsigned char)*s)) ? *s - '0'
+                       : toupper((unsigned char)*s) - 'A' + 10;
+        if (digit >= base) break;  /* invalid numeral; force a fail */
+        n = n * (lua_Number)base + (lua_Number)digit;
+        s++;
+      } while (isalnum((unsigned char)*s));
+      s += strspn(s, SPACECHARS);  /* skip trailing spaces */
+      if (s == e) {  /* no invalid trailing characters? */
+        lua_pushnumber(L, (neg) ? -n : n);
         return 1;
-      }
-    }
+      }  /* else not a number */
+    }  /* else not a number */
   }
-  lua_pushnil(L);  /* else not a number */
+  lua_pushnil(L);  /* not a number */
   return 1;
 }
 
@@ -107,57 +113,13 @@ static int luaB_setmetatable (lua_State *L) {
   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");
+    return 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);
@@ -166,6 +128,15 @@ static int luaB_rawequal (lua_State *L) {
 }
 
 
+static int luaB_rawlen (lua_State *L) {
+  int t = lua_type(L, 1);
+  luaL_argcheck(L, t == LUA_TTABLE || t == LUA_TSTRING, 1,
+                   "table or string expected");
+  lua_pushinteger(L, lua_rawlen(L, 1));
+  return 1;
+}
+
+
 static int luaB_rawget (lua_State *L) {
   luaL_checktype(L, 1, LUA_TTABLE);
   luaL_checkany(L, 2);
@@ -184,32 +155,29 @@ static int luaB_rawset (lua_State *L) {
 }
 
 
-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};
+    "count", "step", "setpause", "setstepmul",
+    "setmajorinc", "isrunning", "gen", "inc", 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);
+    LUA_GCCOUNT, LUA_GCSTEP, LUA_GCSETPAUSE, LUA_GCSETSTEPMUL,
+    LUA_GCSETMAJORINC, LUA_GCISRUNNING, LUA_GCGEN, LUA_GCINC};
+  int o = optsnum[luaL_checkoption(L, 1, "collect", opts)];
   int ex = luaL_optint(L, 2, 0);
-  int res = lua_gc(L, optsnum[o], ex);
-  switch (optsnum[o]) {
+  int res = lua_gc(L, o, ex);
+  switch (o) {
     case LUA_GCCOUNT: {
       int b = lua_gc(L, LUA_GCCOUNTB, 0);
       lua_pushnumber(L, res + ((lua_Number)b/1024));
-      return 1;
+      lua_pushinteger(L, b);
+      return 2;
     }
-    case LUA_GCSTEP: {
+    case LUA_GCSTEP: case LUA_GCISRUNNING: {
       lua_pushboolean(L, res);
       return 1;
     }
     default: {
-      lua_pushnumber(L, res);
+      lua_pushinteger(L, res);
       return 1;
     }
   }
@@ -223,6 +191,23 @@ static int luaB_type (lua_State *L) {
 }
 
 
+static int pairsmeta (lua_State *L, const char *method, int iszero,
+                      lua_CFunction iter) {
+  if (!luaL_getmetafield(L, 1, method)) {  /* no metamethod? */
+    luaL_checktype(L, 1, LUA_TTABLE);  /* argument must be a table */
+    lua_pushcfunction(L, iter);  /* will return generator, */
+    lua_pushvalue(L, 1);  /* state, */
+    if (iszero) lua_pushinteger(L, 0);  /* and initial value */
+    else lua_pushnil(L);
+  }
+  else {
+    lua_pushvalue(L, 1);  /* argument 'self' to metamethod */
+    lua_call(L, 1, 3);  /* get 3 values from metamethod */
+  }
+  return 3;
+}
+
+
 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 */
@@ -236,11 +221,7 @@ static int luaB_next (lua_State *L) {
 
 
 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;
+  return pairsmeta(L, "__pairs", 0, luaB_next);
 }
 
 
@@ -250,21 +231,17 @@ static int ipairsaux (lua_State *L) {
   i++;  /* next value */
   lua_pushinteger(L, i);
   lua_rawgeti(L, 1, i);
-  return (lua_isnil(L, -1)) ? 0 : 2;
+  return (lua_isnil(L, -1)) ? 1 : 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;
+  return pairsmeta(L, "__ipairs", 1, ipairsaux);
 }
 
 
 static int load_aux (lua_State *L, int status) {
-  if (status == 0)  /* OK? */
+  if (status == LUA_OK)
     return 1;
   else {
     lua_pushnil(L);
@@ -274,14 +251,6 @@ static int load_aux (lua_State *L, int status) {
 }
 
 
-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));
@@ -289,13 +258,49 @@ static int luaB_loadfile (lua_State *L) {
 
 
 /*
+** {======================================================
+** Generic Read function
+** =======================================================
+*/
+
+
+typedef struct {
+char c;
+  const char *mode;
+} loaddata;
+
+
+/*
+** check whether a chunk (prefix in 's') satisfies given 'mode'
+** ('t' for text, 'b' for binary). Returns error message (also
+** pushed on the stack) in case of errors.
+*/
+static const char *checkrights (lua_State *L, const char *mode, const char *s) {
+  if (strchr(mode, 'b') == NULL && *s == LUA_SIGNATURE[0])
+    return lua_pushstring(L, "attempt to load a binary chunk");
+  if (strchr(mode, 't') == NULL && *s != LUA_SIGNATURE[0])
+    return lua_pushstring(L, "attempt to load a text chunk");
+  return NULL;  /* chunk in allowed format */
+}
+
+
+/*
+** reserved slot, above all arguments, to hold a copy of the returned
+** string to avoid it being collected while parsed. 'load' has four
+** optional arguments (chunk, source name, mode, and environment).
+*/
+#define RESERVEDSLOT	5
+
+
+/*
 ** 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 */
+  const char *s;
+  loaddata *ld = (loaddata *)ud;
   luaL_checkstack(L, 2, "too many nested functions");
   lua_pushvalue(L, 1);  /* get function */
   lua_call(L, 0, 1);  /* call it */
@@ -303,58 +308,72 @@ static const char *generic_reader (lua_State *L, void *ud, size_t *size) {
     *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 if ((s = lua_tostring(L, -1)) != NULL) {
+    if (ld->mode != NULL) {  /* first time? */
+      s = checkrights(L, ld->mode, s);  /* check mode */
+      ld->mode = NULL;  /* to avoid further checks */
+      if (s) luaL_error(L, s);
+    }
+    lua_replace(L, RESERVEDSLOT);  /* save string in reserved slot */
+    return lua_tolstring(L, RESERVEDSLOT, size);
+  }
+  else {
+    luaL_error(L, "reader function must return a string");
+    return NULL;  /* to avoid warnings */
   }
-  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);
+  size_t l;
+  int top = lua_gettop(L);
+  const char *s = lua_tolstring(L, 1, &l);
+  const char *mode = luaL_optstring(L, 3, "bt");
+  if (s != NULL) {  /* loading a string? */
+    const char *chunkname = luaL_optstring(L, 2, s);
+    status = (checkrights(L, mode, s) != NULL)
+           || luaL_loadbuffer(L, s, l, chunkname);
+  }
+  else {  /* loading from a reader function */
+    const char *chunkname = luaL_optstring(L, 2, "=(load)");
+    loaddata ld;
+    ld.mode = mode;
+    luaL_checktype(L, 1, LUA_TFUNCTION);
+    lua_settop(L, RESERVEDSLOT);  /* create reserved slot */
+    status = lua_load(L, generic_reader, &ld, chunkname);
+  }
+  if (status == LUA_OK && top >= 4) {  /* is there an 'env' argument */
+    lua_pushvalue(L, 4);  /* environment for loaded function */
+    lua_setupvalue(L, -2, 1);  /* set it as 1st upvalue */
+  }
   return load_aux(L, status);
 }
 
+/* }====================================================== */
+
+
+static int dofilecont (lua_State *L) {
+  return lua_gettop(L) - 1;
+}
+
 
 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;
+  lua_settop(L, 1);
+  if (luaL_loadfile(L, fname) != LUA_OK) lua_error(L);
+  lua_callk(L, 0, LUA_MULTRET, 0, dofilecont);
+  return dofilecont(L);
 }
 
 
 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) == '#') {
@@ -371,11 +390,25 @@ static int luaB_select (lua_State *L) {
 }
 
 
+static int pcallcont (lua_State *L) {
+  int errfunc = 0;  /* =0 to avoid warnings */
+  int status = lua_getctx(L, &errfunc);
+  lua_assert(status != LUA_OK);
+  lua_pushboolean(L, (status == LUA_YIELD));  /* first result (status) */
+  if (errfunc)  /* came from xpcall? */
+    lua_replace(L, 1);  /* put first result in place of error function */
+  else  /* came from pcall */
+    lua_insert(L, 1);  /* open space for first result */
+  return lua_gettop(L);
+}
+
+
 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));
+  status = lua_pcallk(L, lua_gettop(L) - 1, LUA_MULTRET, 0, 0, pcallcont);
+  luaL_checkstack(L, 1, NULL);
+  lua_pushboolean(L, (status == LUA_OK));
   lua_insert(L, 1);
   return lua_gettop(L);  /* return status + all results */
 }
@@ -383,11 +416,14 @@ static int luaB_pcall (lua_State *L) {
 
 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));
+  int n = lua_gettop(L);
+  luaL_argcheck(L, n >= 2, 2, "value expected");
+  lua_pushvalue(L, 1);  /* exchange function... */
+  lua_copy(L, 2, 1);  /* ...and error handler */
+  lua_replace(L, 2);
+  status = lua_pcallk(L, n - 2, LUA_MULTRET, 1, 1, pcallcont);
+  luaL_checkstack(L, 1, NULL);
+  lua_pushboolean(L, (status == LUA_OK));
   lua_replace(L, 1);
   return lua_gettop(L);  /* return status + all results */
 }
@@ -395,51 +431,7 @@ static int luaB_xpcall (lua_State *L) {
 
 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);
+  luaL_tolstring(L, 1, NULL);
   return 1;
 }
 
@@ -449,205 +441,40 @@ static const luaL_Reg base_funcs[] = {
   {"collectgarbage", luaB_collectgarbage},
   {"dofile", luaB_dofile},
   {"error", luaB_error},
-  {"gcinfo", luaB_gcinfo},
-  {"getfenv", luaB_getfenv},
   {"getmetatable", luaB_getmetatable},
+  {"ipairs", luaB_ipairs},
   {"loadfile", luaB_loadfile},
   {"load", luaB_load},
-  {"loadstring", luaB_loadstring},
+#if defined(LUA_COMPAT_LOADSTRING)
+  {"loadstring", luaB_load},
+#endif
   {"next", luaB_next},
+  {"pairs", luaB_pairs},
   {"pcall", luaB_pcall},
   {"print", luaB_print},
   {"rawequal", luaB_rawequal},
+  {"rawlen", luaB_rawlen},
   {"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) {
+LUAMOD_API int luaopen_base (lua_State *L) {
   /* set global _G */
-  lua_pushvalue(L, LUA_GLOBALSINDEX);
-  lua_setglobal(L, "_G");
+  lua_pushglobaltable(L);
+  lua_pushglobaltable(L);
+  lua_setfield(L, -2, "_G");
   /* open lib into global table */
-  luaL_register(L, "_G", base_funcs);
+  luaL_setfuncs(L, base_funcs, 0);
   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;
+  lua_setfield(L, -2, "_VERSION");  /* set global _VERSION */
+  return 1;
 }
 
diff --git a/src/lbitlib.c b/src/lbitlib.c
new file mode 100755
index 0000000..7533b85
--- /dev/null
+++ b/src/lbitlib.c
@@ -0,0 +1,209 @@
+/*
+** $Id: lbitlib.c,v 1.16 2011/06/20 16:35:23 roberto Exp $
+** Standard library for bitwise operations
+** See Copyright Notice in lua.h
+*/
+
+#define lbitlib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+/* number of bits to consider in a number */
+#if !defined(LUA_NBITS)
+#define LUA_NBITS	32
+#endif
+
+
+#define ALLONES		(~(((~(lua_Unsigned)0) << (LUA_NBITS - 1)) << 1))
+
+/* macro to trim extra bits */
+#define trim(x)		((x) & ALLONES)
+
+
+/* builds a number with 'n' ones (1 <= n <= LUA_NBITS) */
+#define mask(n)		(~((ALLONES << 1) << ((n) - 1)))
+
+
+typedef lua_Unsigned b_uint;
+
+
+
+static b_uint andaux (lua_State *L) {
+  int i, n = lua_gettop(L);
+  b_uint r = ~(b_uint)0;
+  for (i = 1; i <= n; i++)
+    r &= luaL_checkunsigned(L, i);
+  return trim(r);
+}
+
+
+static int b_and (lua_State *L) {
+  b_uint r = andaux(L);
+  lua_pushunsigned(L, r);
+  return 1;
+}
+
+
+static int b_test (lua_State *L) {
+  b_uint r = andaux(L);
+  lua_pushboolean(L, r != 0);
+  return 1;
+}
+
+
+static int b_or (lua_State *L) {
+  int i, n = lua_gettop(L);
+  b_uint r = 0;
+  for (i = 1; i <= n; i++)
+    r |= luaL_checkunsigned(L, i);
+  lua_pushunsigned(L, trim(r));
+  return 1;
+}
+
+
+static int b_xor (lua_State *L) {
+  int i, n = lua_gettop(L);
+  b_uint r = 0;
+  for (i = 1; i <= n; i++)
+    r ^= luaL_checkunsigned(L, i);
+  lua_pushunsigned(L, trim(r));
+  return 1;
+}
+
+
+static int b_not (lua_State *L) {
+  b_uint r = ~luaL_checkunsigned(L, 1);
+  lua_pushunsigned(L, trim(r));
+  return 1;
+}
+
+
+static int b_shift (lua_State *L, b_uint r, int i) {
+  if (i < 0) {  /* shift right? */
+    i = -i;
+    r = trim(r);
+    if (i >= LUA_NBITS) r = 0;
+    else r >>= i;
+  }
+  else {  /* shift left */
+    if (i >= LUA_NBITS) r = 0;
+    else r <<= i;
+    r = trim(r);
+  }
+  lua_pushunsigned(L, r);
+  return 1;
+}
+
+
+static int b_lshift (lua_State *L) {
+  return b_shift(L, luaL_checkunsigned(L, 1), luaL_checkint(L, 2));
+}
+
+
+static int b_rshift (lua_State *L) {
+  return b_shift(L, luaL_checkunsigned(L, 1), -luaL_checkint(L, 2));
+}
+
+
+static int b_arshift (lua_State *L) {
+  b_uint r = luaL_checkunsigned(L, 1);
+  int i = luaL_checkint(L, 2);
+  if (i < 0 || !(r & ((b_uint)1 << (LUA_NBITS - 1))))
+    return b_shift(L, r, -i);
+  else {  /* arithmetic shift for 'negative' number */
+    if (i >= LUA_NBITS) r = ALLONES;
+    else
+      r = trim((r >> i) | ~(~(b_uint)0 >> i));  /* add signal bit */
+    lua_pushunsigned(L, r);
+    return 1;
+  }
+}
+
+
+static int b_rot (lua_State *L, int i) {
+  b_uint r = luaL_checkunsigned(L, 1);
+  i &= (LUA_NBITS - 1);  /* i = i % NBITS */
+  r = trim(r);
+  r = (r << i) | (r >> (LUA_NBITS - i));
+  lua_pushunsigned(L, trim(r));
+  return 1;
+}
+
+
+static int b_lrot (lua_State *L) {
+  return b_rot(L, luaL_checkint(L, 2));
+}
+
+
+static int b_rrot (lua_State *L) {
+  return b_rot(L, -luaL_checkint(L, 2));
+}
+
+
+/*
+** get field and width arguments for field-manipulation functions,
+** checking whether they are valid
+*/
+static int fieldargs (lua_State *L, int farg, int *width) {
+  int f = luaL_checkint(L, farg);
+  int w = luaL_optint(L, farg + 1, 1);
+  luaL_argcheck(L, 0 <= f, farg, "field cannot be negative");
+  luaL_argcheck(L, 0 < w, farg + 1, "width must be positive");
+  if (f + w > LUA_NBITS)
+    luaL_error(L, "trying to access non-existent bits");
+  *width = w;
+  return f;
+}
+
+
+static int b_extract (lua_State *L) {
+  int w;
+  b_uint r = luaL_checkunsigned(L, 1);
+  int f = fieldargs(L, 2, &w);
+  r = (r >> f) & mask(w);
+  lua_pushunsigned(L, r);
+  return 1;
+}
+
+
+static int b_replace (lua_State *L) {
+  int w;
+  b_uint r = luaL_checkunsigned(L, 1);
+  b_uint v = luaL_checkunsigned(L, 2);
+  int f = fieldargs(L, 3, &w);
+  int m = mask(w);
+  v &= m;  /* erase bits outside given width */
+  r = (r & ~(m << f)) | (v << f);
+  lua_pushunsigned(L, r);
+  return 1;
+}
+
+
+static const luaL_Reg bitlib[] = {
+  {"arshift", b_arshift},
+  {"band", b_and},
+  {"bnot", b_not},
+  {"bor", b_or},
+  {"bxor", b_xor},
+  {"btest", b_test},
+  {"extract", b_extract},
+  {"lrotate", b_lrot},
+  {"lshift", b_lshift},
+  {"replace", b_replace},
+  {"rrotate", b_rrot},
+  {"rshift", b_rshift},
+  {NULL, NULL}
+};
+
+
+
+LUAMOD_API int luaopen_bit32 (lua_State *L) {
+  luaL_newlib(L, bitlib);
+  return 1;
+}
+
diff --git a/src/lcode.c b/src/lcode.c
index 679cb9c..00966a1 100644..100755
--- a/src/lcode.c
+++ b/src/lcode.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lcode.c,v 2.25.1.5 2011/01/31 14:53:16 roberto Exp $
+** $Id: lcode.c,v 2.56 2011/05/31 18:27:56 roberto Exp $
 ** Code generator for Lua
 ** See Copyright Notice in lua.h
 */
@@ -21,7 +21,9 @@
 #include "lobject.h"
 #include "lopcodes.h"
 #include "lparser.h"
+#include "lstring.h"
 #include "ltable.h"
+#include "lvm.h"
 
 
 #define hasjumps(e)	((e)->t != (e)->f)
@@ -34,25 +36,23 @@ static int isnumeral(expdesc *e) {
 
 void luaK_nil (FuncState *fs, int from, int n) {
   Instruction *previous;
+  int l = from + n - 1;  /* last register to set nil */
   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;
-        }
+    previous = &fs->f->code[fs->pc-1];
+    if (GET_OPCODE(*previous) == OP_LOADNIL) {
+      int pfrom = GETARG_A(*previous);
+      int pl = pfrom + GETARG_B(*previous);
+      if ((pfrom <= from && from <= pl + 1) ||
+          (from <= pfrom && pfrom <= l + 1)) {  /* can connect both? */
+        if (pfrom < from) from = pfrom;  /* from = min(from, pfrom) */ 
+        if (pl > l) l = pl;  /* l = max(l, pl) */ 
+        SETARG_A(*previous, from);
+        SETARG_B(*previous, l - from);
+        return;
       }
-    }
+    }  /* else go through */
   }
-  luaK_codeABC(fs, OP_LOADNIL, from, from+n-1, 0);  /* else no optimization */
+  luaK_codeABC(fs, OP_LOADNIL, from, n - 1, 0);  /* else no optimization */
 }
 
 
@@ -176,6 +176,19 @@ void luaK_patchlist (FuncState *fs, int list, int target) {
 }
 
 
+LUAI_FUNC void luaK_patchclose (FuncState *fs, int list, int level) {
+  level++;  /* argument is +1 to reserve 0 as non-op */
+  while (list != NO_JUMP) {
+    int next = getjump(fs, list);
+    lua_assert(GET_OPCODE(fs->f->code[list]) == OP_JMP &&
+                (GETARG_A(fs->f->code[list]) == 0 ||
+                 GETARG_A(fs->f->code[list]) >= level));
+    SETARG_A(fs->f->code[list], level);
+    list = next;
+  }
+}
+
+
 void luaK_patchtohere (FuncState *fs, int list) {
   luaK_getlabel(fs);
   luaK_concat(fs, &fs->jpc, list);
@@ -196,6 +209,55 @@ void luaK_concat (FuncState *fs, int *l1, int l2) {
 }
 
 
+static int luaK_code (FuncState *fs, Instruction i) {
+  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, "opcodes");
+  f->code[fs->pc] = i;
+  /* save corresponding line information */
+  luaM_growvector(fs->L, f->lineinfo, fs->pc, f->sizelineinfo, int,
+                  MAX_INT, "opcodes");
+  f->lineinfo[fs->pc] = fs->ls->lastline;
+  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);
+  lua_assert(a <= MAXARG_A && b <= MAXARG_B && c <= MAXARG_C);
+  return luaK_code(fs, CREATE_ABC(o, a, b, c));
+}
+
+
+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);
+  lua_assert(a <= MAXARG_A && bc <= MAXARG_Bx);
+  return luaK_code(fs, CREATE_ABx(o, a, bc));
+}
+
+
+static int codeextraarg (FuncState *fs, int a) {
+  lua_assert(a <= MAXARG_Ax);
+  return luaK_code(fs, CREATE_Ax(OP_EXTRAARG, a));
+}
+
+
+int luaK_codek (FuncState *fs, int reg, int k) {
+  if (k <= MAXARG_Bx)
+    return luaK_codeABx(fs, OP_LOADK, reg, k);
+  else {
+    int p = luaK_codeABx(fs, OP_LOADKX, reg, 0);
+    codeextraarg(fs, k);
+    return p;
+  }
+}
+
+
 void luaK_checkstack (FuncState *fs, int n) {
   int newstack = fs->freereg + n;
   if (newstack > fs->f->maxstacksize) {
@@ -222,28 +284,33 @@ static void freereg (FuncState *fs, int reg) {
 
 static void freeexp (FuncState *fs, expdesc *e) {
   if (e->k == VNONRELOC)
-    freereg(fs, e->u.s.info);
+    freereg(fs, e->u.info);
 }
 
 
-static int addk (FuncState *fs, TValue *k, TValue *v) {
+static int addk (FuncState *fs, TValue *key, TValue *v) {
   lua_State *L = fs->L;
-  TValue *idx = luaH_set(L, fs->h, k);
+  TValue *idx = luaH_set(L, fs->h, key);
   Proto *f = fs->f;
-  int oldsize = f->sizek;
+  int k, oldsize;
   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++;
+    lua_Number n = nvalue(idx);
+    lua_number2int(k, n);
+    if (luaV_rawequalobj(&f->k[k], v))
+      return k;
+    /* else may be a collision (e.g., between 0.0 and "\0\0\0\0\0\0\0\0");
+       go through and create a new entry for this value */
   }
+  /* constant not found; create a new entry */
+  oldsize = f->sizek;
+  k = fs->nk;
+  setnvalue(idx, cast_num(k));
+  luaM_growvector(L, f->k, k, f->sizek, TValue, MAXARG_Ax, "constants");
+  while (oldsize < f->sizek) setnilvalue(&f->k[oldsize++]);
+  setobj(L, &f->k[k], v);
+  fs->nk++;
+  luaC_barrier(L, f, v);
+  return k;
 }
 
 
@@ -255,9 +322,20 @@ int luaK_stringK (FuncState *fs, TString *s) {
 
 
 int luaK_numberK (FuncState *fs, lua_Number r) {
+  int n;
+  lua_State *L = fs->L;
   TValue o;
   setnvalue(&o, r);
-  return addk(fs, &o, &o);
+  if (r == 0 || luai_numisnan(NULL, r)) {  /* handle -0 and NaN */
+    /* use raw representation as key to avoid numeric problems */
+    setsvalue(L, L->top, luaS_newlstr(L, (char *)&r, sizeof(r)));
+     incr_top(L);
+     n = addk(fs, L->top - 1, &o);
+     L->top--;
+  }
+  else
+    n = addk(fs, &o, &o);  /* regular case */
+  return n;
 }
 
 
@@ -292,7 +370,7 @@ void luaK_setreturns (FuncState *fs, expdesc *e, int nresults) {
 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));
+    e->u.info = GETARG_A(getcode(fs, e));
   }
   else if (e->k == VVARARG) {
     SETARG_B(getcode(fs, e), 2);
@@ -308,19 +386,18 @@ void luaK_dischargevars (FuncState *fs, expdesc *e) {
       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->u.info = luaK_codeABC(fs, OP_GETUPVAL, 0, e->u.info, 0);
       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);
+      OpCode op = OP_GETTABUP;  /* assume 't' is in an upvalue */
+      freereg(fs, e->u.ind.idx);
+      if (e->u.ind.vt == VLOCAL) {  /* 't' is in a register? */
+        freereg(fs, e->u.ind.t);
+        op = OP_GETTABLE;
+      }
+      e->u.info = luaK_codeABC(fs, op, 0, e->u.ind.t, e->u.ind.idx);
       e->k = VRELOCABLE;
       break;
     }
@@ -352,11 +429,11 @@ static void discharge2reg (FuncState *fs, expdesc *e, int reg) {
       break;
     }
     case VK: {
-      luaK_codeABx(fs, OP_LOADK, reg, e->u.s.info);
+      luaK_codek(fs, reg, e->u.info);
       break;
     }
     case VKNUM: {
-      luaK_codeABx(fs, OP_LOADK, reg, luaK_numberK(fs, e->u.nval));
+      luaK_codek(fs, reg, luaK_numberK(fs, e->u.nval));
       break;
     }
     case VRELOCABLE: {
@@ -365,8 +442,8 @@ static void discharge2reg (FuncState *fs, expdesc *e, int reg) {
       break;
     }
     case VNONRELOC: {
-      if (reg != e->u.s.info)
-        luaK_codeABC(fs, OP_MOVE, reg, e->u.s.info, 0);
+      if (reg != e->u.info)
+        luaK_codeABC(fs, OP_MOVE, reg, e->u.info, 0);
       break;
     }
     default: {
@@ -374,7 +451,7 @@ static void discharge2reg (FuncState *fs, expdesc *e, int reg) {
       return;  /* nothing to do... */
     }
   }
-  e->u.s.info = reg;
+  e->u.info = reg;
   e->k = VNONRELOC;
 }
 
@@ -390,7 +467,7 @@ static void discharge2anyreg (FuncState *fs, expdesc *e) {
 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 */
+    luaK_concat(fs, &e->t, e->u.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 */
@@ -406,7 +483,7 @@ static void exp2reg (FuncState *fs, expdesc *e, int reg) {
     patchlistaux(fs, e->t, final, reg, p_t);
   }
   e->f = e->t = NO_JUMP;
-  e->u.s.info = reg;
+  e->u.info = reg;
   e->k = VNONRELOC;
 }
 
@@ -422,14 +499,20 @@ void luaK_exp2nextreg (FuncState *fs, expdesc *e) {
 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;
+    if (!hasjumps(e)) return e->u.info;  /* exp is already in a register */
+    if (e->u.info >= fs->nactvar) {  /* reg. is not a local? */
+      exp2reg(fs, e, e->u.info);  /* put value on it */
+      return e->u.info;
     }
   }
   luaK_exp2nextreg(fs, e);  /* default */
-  return e->u.s.info;
+  return e->u.info;
+}
+
+
+void luaK_exp2anyregup (FuncState *fs, expdesc *e) {
+  if (e->k != VUPVAL || hasjumps(e))
+    luaK_exp2anyreg(fs, e);
 }
 
 
@@ -444,22 +527,24 @@ void luaK_exp2val (FuncState *fs, expdesc *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));
+      if (fs->nk <= MAXINDEXRK) {  /* constant fits in RK operand? */
+        e->u.info = (e->k == VNIL) ? nilK(fs) : boolK(fs, (e->k == VTRUE));
         e->k = VK;
-        return RKASK(e->u.s.info);
+        return RKASK(e->u.info);
       }
       else break;
     }
+    case VKNUM: {
+      e->u.info = luaK_numberK(fs, e->u.nval);
+      e->k = VK;
+      /* go through */
+    }
     case VK: {
-      if (e->u.s.info <= MAXINDEXRK)  /* constant fit in argC? */
-        return RKASK(e->u.s.info);
+      if (e->u.info <= MAXINDEXRK)  /* constant fits in argC? */
+        return RKASK(e->u.info);
       else break;
     }
     default: break;
@@ -473,22 +558,18 @@ void luaK_storevar (FuncState *fs, expdesc *var, expdesc *ex) {
   switch (var->k) {
     case VLOCAL: {
       freeexp(fs, ex);
-      exp2reg(fs, ex, var->u.s.info);
+      exp2reg(fs, ex, var->u.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);
+      luaK_codeABC(fs, OP_SETUPVAL, e, var->u.info, 0);
       break;
     }
     case VINDEXED: {
+      OpCode op = (var->u.ind.vt == VLOCAL) ? OP_SETTABLE : OP_SETTABUP;
       int e = luaK_exp2RK(fs, ex);
-      luaK_codeABC(fs, OP_SETTABLE, var->u.s.info, var->u.s.aux, e);
+      luaK_codeABC(fs, op, var->u.ind.t, var->u.ind.idx, e);
       break;
     }
     default: {
@@ -501,20 +582,20 @@ void luaK_storevar (FuncState *fs, expdesc *var, expdesc *ex) {
 
 
 void luaK_self (FuncState *fs, expdesc *e, expdesc *key) {
-  int func;
+  int ereg;
   luaK_exp2anyreg(fs, e);
+  ereg = e->u.info;  /* register where 'e' was placed */
   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->u.info = fs->freereg;  /* base register for op_self */
   e->k = VNONRELOC;
+  luaK_reserveregs(fs, 2);  /* function and 'self' produced by op_self */
+  luaK_codeABC(fs, OP_SELF, e->u.info, ereg, luaK_exp2RK(fs, key));
+  freeexp(fs, key);
 }
 
 
 static void invertjump (FuncState *fs, expdesc *e) {
-  Instruction *pc = getjumpcontrol(fs, e->u.s.info);
+  Instruction *pc = getjumpcontrol(fs, e->u.info);
   lua_assert(testTMode(GET_OPCODE(*pc)) && GET_OPCODE(*pc) != OP_TESTSET &&
                                            GET_OPCODE(*pc) != OP_TEST);
   SETARG_A(*pc, !(GETARG_A(*pc)));
@@ -532,7 +613,7 @@ static int jumponcond (FuncState *fs, expdesc *e, int cond) {
   }
   discharge2anyreg(fs, e);
   freeexp(fs, e);
-  return condjump(fs, OP_TESTSET, NO_REG, e->u.s.info, cond);
+  return condjump(fs, OP_TESTSET, NO_REG, e->u.info, cond);
 }
 
 
@@ -540,13 +621,13 @@ 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 VJMP: {
       invertjump(fs, e);
-      pc = e->u.s.info;
+      pc = e->u.info;
+      break;
+    }
+    case VK: case VKNUM: case VTRUE: {
+      pc = NO_JUMP;  /* always true; do nothing */
       break;
     }
     default: {
@@ -564,12 +645,12 @@ 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 */
+    case VJMP: {
+      pc = e->u.info;
       break;
     }
-    case VJMP: {
-      pc = e->u.s.info;
+    case VNIL: case VFALSE: {
+      pc = NO_JUMP;  /* always false; do nothing */
       break;
     }
     default: {
@@ -602,7 +683,7 @@ static void codenot (FuncState *fs, expdesc *e) {
     case VNONRELOC: {
       discharge2anyreg(fs, e);
       freeexp(fs, e);
-      e->u.s.info = luaK_codeABC(fs, OP_NOT, 0, e->u.s.info, 0);
+      e->u.info = luaK_codeABC(fs, OP_NOT, 0, e->u.info, 0);
       e->k = VRELOCABLE;
       break;
     }
@@ -619,38 +700,28 @@ static void codenot (FuncState *fs, expdesc *e) {
 
 
 void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k) {
-  t->u.s.aux = luaK_exp2RK(fs, k);
+  lua_assert(!hasjumps(t));
+  t->u.ind.t = t->u.info;
+  t->u.ind.idx = luaK_exp2RK(fs, k);
+  t->u.ind.vt = (t->k == VUPVAL) ? VUPVAL
+                                 : check_exp(vkisinreg(t->k), VLOCAL);
   t->k = VINDEXED;
 }
 
 
 static int constfolding (OpCode op, expdesc *e1, expdesc *e2) {
-  lua_Number v1, v2, r;
+  lua_Number 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 */
+  if ((op == OP_DIV || op == OP_MOD) && e2->u.nval == 0)
+    return 0;  /* do not attempt to divide by 0 */
+  r = luaO_arith(op - OP_ADD + LUA_OPADD, e1->u.nval, e2->u.nval);
   e1->u.nval = r;
   return 1;
 }
 
 
-static void codearith (FuncState *fs, OpCode op, expdesc *e1, expdesc *e2) {
+static void codearith (FuncState *fs, OpCode op,
+                       expdesc *e1, expdesc *e2, int line) {
   if (constfolding(op, e1, e2))
     return;
   else {
@@ -664,8 +735,9 @@ static void codearith (FuncState *fs, OpCode op, expdesc *e1, expdesc *e2) {
       freeexp(fs, e2);
       freeexp(fs, e1);
     }
-    e1->u.s.info = luaK_codeABC(fs, op, 0, o1, o2);
+    e1->u.info = luaK_codeABC(fs, op, 0, o1, o2);
     e1->k = VRELOCABLE;
+    luaK_fixline(fs, line);
   }
 }
 
@@ -681,25 +753,28 @@ static void codecomp (FuncState *fs, OpCode op, int cond, expdesc *e1,
     temp = o1; o1 = o2; o2 = temp;  /* o1 <==> o2 */
     cond = 1;
   }
-  e1->u.s.info = condjump(fs, op, cond, o1, o2);
+  e1->u.info = condjump(fs, op, cond, o1, o2);
   e1->k = VJMP;
 }
 
 
-void luaK_prefix (FuncState *fs, UnOpr op, expdesc *e) {
+void luaK_prefix (FuncState *fs, UnOpr op, expdesc *e, int line) {
   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);
+      if (isnumeral(e))  /* minus constant? */
+        e->u.nval = luai_numunm(NULL, e->u.nval);  /* fold it */
+      else {
+        luaK_exp2anyreg(fs, e);
+        codearith(fs, OP_UNM, e, &e2, line);
+      }
       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);
+      codearith(fs, OP_LEN, e, &e2, line);
       break;
     }
     default: lua_assert(0);
@@ -734,7 +809,8 @@ void luaK_infix (FuncState *fs, BinOpr op, expdesc *v) {
 }
 
 
-void luaK_posfix (FuncState *fs, BinOpr op, expdesc *e1, expdesc *e2) {
+void luaK_posfix (FuncState *fs, BinOpr op,
+                  expdesc *e1, expdesc *e2, int line) {
   switch (op) {
     case OPR_AND: {
       lua_assert(e1->t == NO_JUMP);  /* list must be closed */
@@ -753,29 +829,30 @@ void luaK_posfix (FuncState *fs, BinOpr op, expdesc *e1, expdesc *e2) {
     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);
+        lua_assert(e1->u.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;
+        SETARG_B(getcode(fs, e2), e1->u.info);
+        e1->k = VRELOCABLE; e1->u.info = e2->u.info;
       }
       else {
         luaK_exp2nextreg(fs, e2);  /* operand must be on the 'stack' */
-        codearith(fs, OP_CONCAT, e1, e2);
+        codearith(fs, OP_CONCAT, e1, e2, line);
       }
       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;
+    case OPR_ADD: case OPR_SUB: case OPR_MUL: case OPR_DIV:
+    case OPR_MOD: case OPR_POW: {
+      codearith(fs, cast(OpCode, op - OPR_ADD + OP_ADD), e1, e2, line);
+      break;
+    }
+    case OPR_EQ: case OPR_LT: case OPR_LE: {
+      codecomp(fs, cast(OpCode, op - OPR_EQ + OP_EQ), 1, e1, e2);
+      break;
+    }
+    case OPR_NE: case OPR_GT: case OPR_GE: {
+      codecomp(fs, cast(OpCode, op - OPR_NE + OP_EQ), 0, e1, e2);
+      break;
+    }
     default: lua_assert(0);
   }
 }
@@ -786,46 +863,18 @@ void luaK_fixline (FuncState *fs, int 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 {
+  else if (c <= MAXARG_Ax) {
     luaK_codeABC(fs, OP_SETLIST, base, b, 0);
-    luaK_code(fs, cast(Instruction, c), fs->ls->lastline);
+    codeextraarg(fs, c);
   }
+  else
+    luaX_syntaxerror(fs->ls, "constructor too long");
   fs->freereg = base + 1;  /* free registers with list values */
 }
 
diff --git a/src/lcode.h b/src/lcode.h
index b941c60..26a5daa 100644..100755
--- a/src/lcode.h
+++ b/src/lcode.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lcode.h,v 1.48.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lcode.h,v 1.57 2011/04/07 18:14:12 roberto Exp $
 ** Code generator for Lua
 ** See Copyright Notice in lua.h
 */
@@ -21,13 +21,13 @@
 
 
 /*
-** grep "ORDER OPR" if you change these enums
+** grep "ORDER OPR" if you change these enums  (ORDER OP)
 */
 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_EQ, OPR_LT, OPR_LE,
+  OPR_NE, OPR_GT, OPR_GE,
   OPR_AND, OPR_OR,
   OPR_NOBINOPR
 } BinOpr;
@@ -36,14 +36,17 @@ typedef enum 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 getcode(fs,e)	((fs)->f->code[(e)->u.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)
 
+#define luaK_jumpto(fs,t)	luaK_patchlist(fs, luaK_jump(fs), t)
+
 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 int luaK_codek (FuncState *fs, int reg, int k);
 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);
@@ -52,6 +55,7 @@ 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_exp2anyregup (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);
@@ -65,11 +69,13 @@ 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_patchclose (FuncState *fs, int list, int level);
 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_prefix (FuncState *fs, UnOpr op, expdesc *v, int line);
 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_posfix (FuncState *fs, BinOpr op, expdesc *v1,
+                            expdesc *v2, int line);
 LUAI_FUNC void luaK_setlist (FuncState *fs, int base, int nelems, int tostore);
 
 
diff --git a/src/lcorolib.c b/src/lcorolib.c
new file mode 100755
index 0000000..981ca38
--- /dev/null
+++ b/src/lcorolib.c
@@ -0,0 +1,154 @@
+/*
+** $Id: lcorolib.c,v 1.2 2010/07/02 11:38:13 roberto Exp $
+** Coroutine Library
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stdlib.h>
+
+
+#define lcorolib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+static int auxresume (lua_State *L, lua_State *co, int narg) {
+  int status;
+  if (!lua_checkstack(co, narg)) {
+    lua_pushliteral(L, "too many arguments to resume");
+    return -1;  /* error flag */
+  }
+  if (lua_status(co) == LUA_OK && lua_gettop(co) == 0) {
+    lua_pushliteral(L, "cannot resume dead coroutine");
+    return -1;  /* error flag */
+  }
+  lua_xmove(L, co, narg);
+  status = lua_resume(co, narg);
+  if (status == LUA_OK || status == LUA_YIELD) {
+    int nres = lua_gettop(co);
+    if (!lua_checkstack(L, nres + 1)) {
+      lua_pop(co, nres);  /* remove results anyway */
+      lua_pushliteral(L, "too many results to resume");
+      return -1;  /* error flag */
+    }
+    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_checktype(L, 1, LUA_TFUNCTION);
+  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_costatus (lua_State *L) {
+  lua_State *co = lua_tothread(L, 1);
+  luaL_argcheck(L, co, 1, "coroutine expected");
+  if (L == co) lua_pushliteral(L, "running");
+  else {
+    switch (lua_status(co)) {
+      case LUA_YIELD:
+        lua_pushliteral(L, "suspended");
+        break;
+      case LUA_OK: {
+        lua_Debug ar;
+        if (lua_getstack(co, 0, &ar) > 0)  /* does it have frames? */
+          lua_pushliteral(L, "normal");  /* it is running */
+        else if (lua_gettop(co) == 0)
+            lua_pushliteral(L, "dead");
+        else
+          lua_pushliteral(L, "suspended");  /* initial state */
+        break;
+      }
+      default:  /* some error occurred */
+        lua_pushliteral(L, "dead");
+        break;
+    }
+  }
+  return 1;
+}
+
+
+static int luaB_corunning (lua_State *L) {
+  int ismain = lua_pushthread(L);
+  lua_pushboolean(L, ismain);
+  return 2;
+}
+
+
+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}
+};
+
+
+
+LUAMOD_API int luaopen_coroutine (lua_State *L) {
+  luaL_newlib(L, co_funcs);
+  return 1;
+}
+
diff --git a/src/lctype.c b/src/lctype.c
new file mode 100755
index 0000000..387c93a
--- /dev/null
+++ b/src/lctype.c
@@ -0,0 +1,49 @@
+/*
+** $Id: lctype.c,v 1.10 2011/06/24 12:25:33 roberto Exp $
+** 'ctype' functions for Lua
+** See Copyright Notice in lua.h
+*/
+
+#include "lctype.h"
+
+#if !LUA_USE_CTYPE	/* { */
+
+#include <limits.h>
+
+LUAI_DDEF const lu_byte luai_ctype_[UCHAR_MAX + 2] = {
+  0x00,  /* EOZ */
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,	/* 0. */
+  0x00,  0x08,  0x08,  0x08,  0x08,  0x08,  0x00,  0x00,
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,	/* 1. */
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,
+  0x0c,  0x04,  0x04,  0x04,  0x04,  0x04,  0x04,  0x04,	/* 2. */
+  0x04,  0x04,  0x04,  0x04,  0x04,  0x04,  0x04,  0x04,
+  0x16,  0x16,  0x16,  0x16,  0x16,  0x16,  0x16,  0x16,	/* 3. */
+  0x16,  0x16,  0x04,  0x04,  0x04,  0x04,  0x04,  0x04,
+  0x04,  0x15,  0x15,  0x15,  0x15,  0x15,  0x15,  0x05,	/* 4. */
+  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,
+  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,	/* 5. */
+  0x05,  0x05,  0x05,  0x04,  0x04,  0x04,  0x04,  0x05,
+  0x04,  0x15,  0x15,  0x15,  0x15,  0x15,  0x15,  0x05,	/* 6. */
+  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,
+  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,  0x05,	/* 7. */
+  0x05,  0x05,  0x05,  0x04,  0x04,  0x04,  0x04,  0x00,
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,	/* 8. */
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,	/* 9. */
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,	/* a. */
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,	/* b. */
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,	/* c. */
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,	/* d. */
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,	/* e. */
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,	/* f. */
+  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,  0x00,
+};
+
+#endif			/* } */
diff --git a/src/lctype.h b/src/lctype.h
new file mode 100755
index 0000000..b24d925
--- /dev/null
+++ b/src/lctype.h
@@ -0,0 +1,95 @@
+/*
+** $Id: lctype.h,v 1.11 2011/06/27 18:22:46 roberto Exp $
+** 'ctype' functions for Lua
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lctype_h
+#define lctype_h
+
+#include "lua.h"
+
+
+/*
+** WARNING: the functions defined here do not necessarily correspond 
+** to the similar functions in the standard C ctype.h. They are
+** optimized for the specific needs of Lua
+*/
+
+#if !defined(LUA_USE_CTYPE)
+
+#if 'A' == 65 && '0' == 48
+/* ASCII case: can use its own tables; faster and fixed */
+#define LUA_USE_CTYPE	0
+#else
+/* must use standard C ctype */
+#define LUA_USE_CTYPE	1
+#endif
+
+#endif
+
+
+#if !LUA_USE_CTYPE	/* { */
+
+#include <limits.h>
+
+#include "llimits.h"
+
+
+#define ALPHABIT	0
+#define DIGITBIT	1
+#define PRINTBIT	2
+#define SPACEBIT	3
+#define XDIGITBIT	4
+
+
+#define MASK(B)		(1 << (B))
+
+
+/*
+** add 1 to char to allow index -1 (EOZ)
+*/
+#define testprop(c,p)	(luai_ctype_[(c)+1] & (p))
+
+/*
+** 'lalpha' (Lua alphabetic) and 'lalnum' (Lua alphanumeric) both include '_'
+*/
+#define lislalpha(c)	testprop(c, MASK(ALPHABIT))
+#define lislalnum(c)	testprop(c, (MASK(ALPHABIT) | MASK(DIGITBIT)))
+#define lisdigit(c)	testprop(c, MASK(DIGITBIT))
+#define lisspace(c)	testprop(c, MASK(SPACEBIT))
+#define lisprint(c)	testprop(c, MASK(PRINTBIT))
+#define lisxdigit(c)	testprop(c, MASK(XDIGITBIT))
+
+/*
+** this 'ltolower' only works for alphabetic characters
+*/
+#define ltolower(c)	((c) | ('A' ^ 'a'))
+
+
+/* two more entries for 0 and -1 (EOZ) */
+LUAI_DDEC const lu_byte luai_ctype_[UCHAR_MAX + 2];
+
+
+#else			/* }{ */
+
+/*
+** use standard C ctypes
+*/
+
+#include <ctype.h>
+
+
+#define lislalpha(c)	(isalpha(c) || (c) == '_')
+#define lislalnum(c)	(isalnum(c) || (c) == '_')
+#define lisdigit(c)	(isdigit(c))
+#define lisspace(c)	(isspace(c))
+#define lisprint(c)	(isprint(c))
+#define lisxdigit(c)	(isxdigit(c))
+
+#define ltolower(c)	(tolower(c))
+
+#endif			/* } */
+
+#endif
+
diff --git a/src/ldblib.c b/src/ldblib.c
index 2027eda..78f6cc0 100644..100755
--- a/src/ldblib.c
+++ b/src/ldblib.c
@@ -1,5 +1,5 @@
 /*
-** $Id: ldblib.c,v 1.104.1.4 2009/08/04 18:50:18 roberto Exp $
+** $Id: ldblib.c,v 1.130 2011/04/08 19:17:36 roberto Exp $
 ** Interface from Lua to its debug API
 ** See Copyright Notice in lua.h
 */
@@ -18,6 +18,9 @@
 #include "lualib.h"
 
 
+#define HOOKKEY		"_HKEY"
+
+
 
 static int db_getregistry (lua_State *L) {
   lua_pushvalue(L, LUA_REGISTRYINDEX);
@@ -39,24 +42,28 @@ static int db_setmetatable (lua_State *L) {
   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;
+  lua_setmetatable(L, 1);
+  return 1;  /* return 1st argument */
 }
 
 
-static int db_getfenv (lua_State *L) {
-  luaL_checkany(L, 1);
-  lua_getfenv(L, 1);
+static int db_getuservalue (lua_State *L) {
+  if (lua_type(L, 1) != LUA_TUSERDATA)
+    lua_pushnil(L);
+  else
+    lua_getuservalue(L, 1);
   return 1;
 }
 
 
-static int db_setfenv (lua_State *L) {
-  luaL_checktype(L, 2, LUA_TTABLE);
+static int db_setuservalue (lua_State *L) {
+  if (lua_type(L, 1) == LUA_TLIGHTUSERDATA)
+    luaL_argerror(L, 1, "full userdata expected, got light userdata");
+  luaL_checktype(L, 1, LUA_TUSERDATA);
+  if (!lua_isnoneornil(L, 2))
+    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");
+  lua_setuservalue(L, 1);
   return 1;
 }
 
@@ -73,6 +80,12 @@ static void settabsi (lua_State *L, const char *i, int v) {
 }
 
 
+static void settabsb (lua_State *L, const char *i, int v) {
+  lua_pushboolean(L, v);
+  lua_setfield(L, -2, i);
+}
+
+
 static lua_State *getthread (lua_State *L, int *arg) {
   if (lua_isthread(L, 1)) {
     *arg = 1;
@@ -100,7 +113,7 @@ 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");
+  const char *options = luaL_optstring(L, arg+2, "flnStu");
   if (lua_isnumber(L, arg+1)) {
     if (!lua_getstack(L1, (int)lua_tointeger(L, arg+1), &ar)) {
       lua_pushnil(L);  /* level out of range */
@@ -127,38 +140,51 @@ static int db_getinfo (lua_State *L) {
   }
   if (strchr(options, 'l'))
     settabsi(L, "currentline", ar.currentline);
-  if (strchr(options, 'u'))
+  if (strchr(options, 'u')) {
     settabsi(L, "nups", ar.nups);
+    settabsi(L, "nparams", ar.nparams);
+    settabsb(L, "isvararg", ar.isvararg);
+  }
   if (strchr(options, 'n')) {
     settabss(L, "name", ar.name);
     settabss(L, "namewhat", ar.namewhat);
   }
+  if (strchr(options, 't'))
+    settabsb(L, "istailcall", ar.istailcall);
   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);
+  int nvar = luaL_checkint(L, arg+2);  /* local-variable index */
+  if (lua_isfunction(L, arg + 1)) {  /* function argument? */
+    lua_pushvalue(L, arg + 1);  /* push function */
+    lua_pushstring(L, lua_getlocal(L, NULL, nvar));  /* push local name */
     return 1;
   }
+  else {  /* stack-level argument */
+    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, nvar);
+    if (name) {
+      lua_xmove(L1, L, 1);  /* push local value */
+      lua_pushstring(L, name);  /* push name */
+      lua_pushvalue(L, -2);  /* re-order */
+      return 2;
+    }
+    else {
+      lua_pushnil(L);  /* no name (nor value) */
+      return 1;
+    }
+  }
 }
 
 
@@ -180,7 +206,6 @@ 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);
@@ -200,15 +225,41 @@ static int db_setupvalue (lua_State *L) {
 }
 
 
+static int checkupval (lua_State *L, int argf, int argnup) {
+  lua_Debug ar;
+  int nup = luaL_checkint(L, argnup);
+  luaL_checktype(L, argf, LUA_TFUNCTION);
+  lua_pushvalue(L, argf);
+  lua_getinfo(L, ">u", &ar);
+  luaL_argcheck(L, 1 <= nup && nup <= ar.nups, argnup, "invalid upvalue index");
+  return nup;
+}
+
+
+static int db_upvalueid (lua_State *L) {
+  int n = checkupval(L, 1, 2);
+  lua_pushlightuserdata(L, lua_upvalueid(L, 1, n));
+  return 1;
+}
 
-static const char KEY_HOOK = 'h';
+
+static int db_upvaluejoin (lua_State *L) {
+  int n1 = checkupval(L, 1, 2);
+  int n2 = checkupval(L, 3, 4);
+  luaL_argcheck(L, !lua_iscfunction(L, 1), 1, "Lua function expected");
+  luaL_argcheck(L, !lua_iscfunction(L, 3), 3, "Lua function expected");
+  lua_upvaluejoin(L, 1, n1, 3, n2);
+  return 0;
+}
+
+
+#define gethooktable(L)	luaL_getsubtable(L, LUA_REGISTRYINDEX, HOOKKEY);
 
 
 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);
+    {"call", "return", "line", "count", "tail call"};
+  gethooktable(L);
   lua_pushlightuserdata(L, L);
   lua_rawget(L, -2);
   if (lua_isfunction(L, -1)) {
@@ -242,19 +293,6 @@ static char *unmakemask (int mask, char *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;
@@ -302,97 +340,55 @@ static int db_gethook (lua_State *L) {
 static int db_debug (lua_State *L) {
   for (;;) {
     char buffer[250];
-    fputs("lua_debug> ", stderr);
+    luai_writestringerror("%s", "lua_debug> ");
     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_pcall(L, 0, 0, 0))
+      luai_writestringerror("%s\n", lua_tostring(L, -1));
     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 `...' */
+static int db_traceback (lua_State *L) {
   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);
+  const char *msg = lua_tostring(L, arg + 1);
+  if (msg == NULL && !lua_isnoneornil(L, arg + 1))  /* non-string 'msg'? */
+    lua_pushvalue(L, arg + 1);  /* return it untouched */
+  else {
+    int level = luaL_optint(L, arg + 2, (L == L1) ? 1 : 0);
+    luaL_traceback(L, L1, msg, level);
   }
-  lua_concat(L, lua_gettop(L) - arg);
   return 1;
 }
 
 
 static const luaL_Reg dblib[] = {
   {"debug", db_debug},
-  {"getfenv", db_getfenv},
+  {"getuservalue", db_getuservalue},
   {"gethook", db_gethook},
   {"getinfo", db_getinfo},
   {"getlocal", db_getlocal},
   {"getregistry", db_getregistry},
   {"getmetatable", db_getmetatable},
   {"getupvalue", db_getupvalue},
-  {"setfenv", db_setfenv},
+  {"upvaluejoin", db_upvaluejoin},
+  {"upvalueid", db_upvalueid},
+  {"setuservalue", db_setuservalue},
   {"sethook", db_sethook},
   {"setlocal", db_setlocal},
   {"setmetatable", db_setmetatable},
   {"setupvalue", db_setupvalue},
-  {"traceback", db_errorfb},
+  {"traceback", db_traceback},
   {NULL, NULL}
 };
 
 
-LUALIB_API int luaopen_debug (lua_State *L) {
-  luaL_register(L, LUA_DBLIBNAME, dblib);
+LUAMOD_API int luaopen_debug (lua_State *L) {
+  luaL_newlib(L, dblib);
   return 1;
 }
 
diff --git a/src/ldebug.c b/src/ldebug.c
index 50ad3d3..a2565cf 100644..100755
--- a/src/ldebug.c
+++ b/src/ldebug.c
@@ -1,5 +1,5 @@
 /*
-** $Id: ldebug.c,v 2.29.1.6 2008/05/08 16:56:26 roberto Exp $
+** $Id: ldebug.c,v 2.82 2011/06/02 19:31:40 roberto Exp $
 ** Debug Interface
 ** See Copyright Notice in lua.h
 */
@@ -33,20 +33,14 @@
 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 currentpc (CallInfo *ci) {
+  lua_assert(isLua(ci));
+  return pcRel(ci->u.l.savedpc, ci_func(ci)->p);
 }
 
 
-static int currentline (lua_State *L, CallInfo *ci) {
-  int pc = currentpc(L, ci);
-  if (pc < 0)
-    return -1;  /* only active lua functions have current-line information */
-  else
-    return getline(ci_func(ci)->l.p, pc);
+static int currentline (CallInfo *ci) {
+  return getfuncline(ci_func(ci)->p, currentpc(ci));
 }
 
 
@@ -58,6 +52,8 @@ LUA_API int lua_sethook (lua_State *L, lua_Hook func, int mask, int count) {
     mask = 0;
     func = NULL;
   }
+  if (isLua(L->ci))
+    L->oldpc = L->ci->u.l.savedpc;
   L->hook = func;
   L->basehookcount = count;
   resethookcount(L);
@@ -84,19 +80,13 @@ LUA_API int lua_gethookcount (lua_State *L) {
 LUA_API int lua_getstack (lua_State *L, int level, lua_Debug *ar) {
   int status;
   CallInfo *ci;
+  if (level < 0) return 0;  /* invalid (negative) level */
   lua_lock(L);
-  for (ci = L->ci; level > 0 && ci > L->base_ci; ci--) {
+  for (ci = L->ci; level > 0 && ci != &L->base_ci; ci = ci->previous)
     level--;
-    if (f_isLua(ci))  /* Lua function? */
-      level -= ci->tailcalls;  /* skip lost tail calls */
-  }
-  if (level == 0 && ci > L->base_ci) {  /* level found? */
-    status = 1;
-    ar->i_ci = cast_int(ci - L->base_ci);
-  }
-  else if (level < 0) {  /* level is of a lost tail call? */
+  if (level == 0 && ci != &L->base_ci) {  /* level found? */
     status = 1;
-    ar->i_ci = 0;
+    ar->i_ci = ci;
   }
   else status = 0;  /* no such level */
   lua_unlock(L);
@@ -104,43 +94,71 @@ LUA_API int lua_getstack (lua_State *L, int level, lua_Debug *ar) {
 }
 
 
-static Proto *getluaproto (CallInfo *ci) {
-  return (isLua(ci) ? ci_func(ci)->l.p : NULL);
+static const char *findvararg (CallInfo *ci, int n, StkId *pos) {
+  int nparams = clLvalue(ci->func)->p->numparams;
+  if (n >= ci->u.l.base - ci->func - nparams)
+    return NULL;  /* no such vararg */
+  else {
+    *pos = ci->func + nparams + n;
+    return "(*vararg)";  /* generic name for any vararg */
+  }
 }
 
 
-static const char *findlocal (lua_State *L, CallInfo *ci, int n) {
-  const char *name;
-  Proto *fp = getluaproto(ci);
-  if (fp && (name = luaF_getlocalname(fp, n, currentpc(L, ci))) != NULL)
-    return name;  /* is a local variable in a Lua function */
-  else {
-    StkId limit = (ci == L->ci) ? L->top : (ci+1)->func;
-    if (limit - ci->base >= n && n > 0)  /* is 'n' inside 'ci' stack? */
-      return "(*temporary)";
+static const char *findlocal (lua_State *L, CallInfo *ci, int n,
+                              StkId *pos) {
+  const char *name = NULL;
+  StkId base;
+  if (isLua(ci)) {
+    if (n < 0)  /* access to vararg values? */
+      return findvararg(ci, -n, pos);
+    else {
+      base = ci->u.l.base;
+      name = luaF_getlocalname(ci_func(ci)->p, n, currentpc(ci));
+    }
+  }
+  else
+    base = ci->func + 1;
+  if (name == NULL) {  /* no 'standard' name? */
+    StkId limit = (ci == L->ci) ? L->top : ci->next->func;
+    if (limit - base >= n && n > 0)  /* is 'n' inside 'ci' stack? */
+      name = "(*temporary)";  /* generic name for any valid slot */
     else
-      return NULL;
+      return NULL;  /* no name */
   }
+  *pos = base + (n - 1);
+  return name;
 }
 
 
 LUA_API const char *lua_getlocal (lua_State *L, const lua_Debug *ar, int n) {
-  CallInfo *ci = L->base_ci + ar->i_ci;
-  const char *name = findlocal(L, ci, n);
+  const char *name;
   lua_lock(L);
-  if (name)
-      luaA_pushobject(L, ci->base + (n - 1));
+  if (ar == NULL) {  /* information about non-active function? */
+    if (!isLfunction(L->top - 1))  /* not a Lua function? */
+      name = NULL;
+    else  /* consider live variables at function start (parameters) */
+      name = luaF_getlocalname(clLvalue(L->top - 1)->p, n, 0);
+  }
+  else {  /* active function; get information through 'ar' */
+    StkId pos = 0;  /* to avoid warnings */
+    name = findlocal(L, ar->i_ci, n, &pos);
+    if (name) {
+      setobj2s(L, L->top, pos);
+      api_incr_top(L);
+    }
+  }
   lua_unlock(L);
   return name;
 }
 
 
 LUA_API const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n) {
-  CallInfo *ci = L->base_ci + ar->i_ci;
-  const char *name = findlocal(L, ci, n);
+  StkId pos = 0;  /* to avoid warnings */
+  const char *name = findlocal(L, ar->i_ci, n, &pos);
   lua_lock(L);
   if (name)
-      setobjs2s(L, ci->base + (n - 1), L->top - 1);
+    setobjs2s(L, pos, L->top - 1);
   L->top--;  /* pop value */
   lua_unlock(L);
   return name;
@@ -148,55 +166,43 @@ LUA_API const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n) {
 
 
 static void funcinfo (lua_Debug *ar, Closure *cl) {
-  if (cl->c.isC) {
+  if (cl == NULL || cl->c.isC) {
     ar->source = "=[C]";
     ar->linedefined = -1;
     ar->lastlinedefined = -1;
     ar->what = "C";
   }
   else {
-    ar->source = getstr(cl->l.p->source);
-    ar->linedefined = cl->l.p->linedefined;
-    ar->lastlinedefined = cl->l.p->lastlinedefined;
+    Proto *p = cl->l.p;
+    ar->source = p->source ? getstr(p->source) : "=?";
+    ar->linedefined = p->linedefined;
+    ar->lastlinedefined = p->lastlinedefined;
     ar->what = (ar->linedefined == 0) ? "main" : "Lua";
   }
   luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE);
 }
 
 
-static void info_tailcall (lua_Debug *ar) {
-  ar->name = ar->namewhat = "";
-  ar->what = "tail";
-  ar->lastlinedefined = ar->linedefined = ar->currentline = -1;
-  ar->source = "=(tail call)";
-  luaO_chunkid(ar->short_src, ar->source, LUA_IDSIZE);
-  ar->nups = 0;
-}
-
-
 static void collectvalidlines (lua_State *L, Closure *f) {
   if (f == NULL || f->c.isC) {
     setnilvalue(L->top);
+    incr_top(L);
   }
   else {
-    Table *t = luaH_new(L, 0, 0);
-    int *lineinfo = f->l.p->lineinfo;
     int i;
+    int *lineinfo = f->l.p->lineinfo;
+    Table *t = luaH_new(L);
+    sethvalue(L, L->top, t);
+    incr_top(L);
     for (i=0; i<f->l.p->sizelineinfo; i++)
-      setbvalue(luaH_setnum(L, t, lineinfo[i]), 1);
-    sethvalue(L, L->top, t); 
+      setbvalue(luaH_setint(L, t, lineinfo[i]), 1);
   }
-  incr_top(L);
 }
 
 
 static int auxgetinfo (lua_State *L, const char *what, lua_Debug *ar,
                     Closure *f, CallInfo *ci) {
   int status = 1;
-  if (f == NULL) {
-    info_tailcall(ar);
-    return status;
-  }
   for (; *what; what++) {
     switch (*what) {
       case 'S': {
@@ -204,11 +210,23 @@ static int auxgetinfo (lua_State *L, const char *what, lua_Debug *ar,
         break;
       }
       case 'l': {
-        ar->currentline = (ci) ? currentline(L, ci) : -1;
+        ar->currentline = (ci && isLua(ci)) ? currentline(ci) : -1;
         break;
       }
       case 'u': {
-        ar->nups = f->c.nupvalues;
+        ar->nups = (f == NULL) ? 0 : f->c.nupvalues;
+        if (f == NULL || f->c.isC) {
+          ar->isvararg = 1;
+          ar->nparams = 0;
+        }
+        else {
+          ar->isvararg = f->l.p->is_vararg;
+          ar->nparams = f->l.p->numparams;
+        }
+        break;
+      }
+      case 't': {
+        ar->istailcall = (ci) ? ci->callstatus & CIST_TAIL : 0;
         break;
       }
       case 'n': {
@@ -231,29 +249,30 @@ static int auxgetinfo (lua_State *L, const char *what, lua_Debug *ar,
 
 LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) {
   int status;
-  Closure *f = NULL;
-  CallInfo *ci = NULL;
+  Closure *cl;
+  CallInfo *ci;
+  StkId func;
   lua_lock(L);
   if (*what == '>') {
-    StkId func = L->top - 1;
-    luai_apicheck(L, ttisfunction(func));
+    ci = NULL;
+    func = L->top - 1;
+    api_check(L, ttisfunction(func), "function expected");
     what++;  /* skip the '>' */
-    f = clvalue(func);
     L->top--;  /* pop function */
   }
-  else if (ar->i_ci != 0) {  /* no tail call? */
-    ci = L->base_ci + ar->i_ci;
+  else {
+    ci = ar->i_ci;
+    func = ci->func;
     lua_assert(ttisfunction(ci->func));
-    f = clvalue(ci->func);
   }
-  status = auxgetinfo(L, what, ar, f, ci);
+  cl = ttisclosure(func) ? clvalue(func) : NULL;
+  status = auxgetinfo(L, what, ar, cl, ci);
   if (strchr(what, 'f')) {
-    if (f == NULL) setnilvalue(L->top);
-    else setclvalue(L, L->top, f);
+    setobjs2s(L, L->top, func);
     incr_top(L);
   }
   if (strchr(what, 'L'))
-    collectvalidlines(L, f);
+    collectvalidlines(L, cl);
   lua_unlock(L);
   return status;
 }
@@ -261,315 +280,222 @@ LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) {
 
 /*
 ** {======================================================
-** Symbolic Execution and code checker
+** Symbolic Execution
 ** =======================================================
 */
 
-#define check(x)		if (!(x)) return 0;
-
-#define checkjump(pt,pc)	check(0 <= pc && pc < pt->sizecode)
-
-#define checkreg(pt,reg)	check((reg) < (pt)->maxstacksize)
-
-
-
-static int precheck (const Proto *pt) {
-  check(pt->maxstacksize <= MAXSTACK);
-  check(pt->numparams+(pt->is_vararg & VARARG_HASARG) <= pt->maxstacksize);
-  check(!(pt->is_vararg & VARARG_NEEDSARG) ||
-              (pt->is_vararg & VARARG_HASARG));
-  check(pt->sizeupvalues <= pt->nups);
-  check(pt->sizelineinfo == pt->sizecode || pt->sizelineinfo == 0);
-  check(pt->sizecode > 0 && GET_OPCODE(pt->code[pt->sizecode-1]) == OP_RETURN);
-  return 1;
-}
-
+static const char *getobjname (lua_State *L, CallInfo *ci, int reg,
+                               const char **name);
 
-#define checkopenop(pt,pc)	luaG_checkopenop((pt)->code[(pc)+1])
 
-int luaG_checkopenop (Instruction i) {
-  switch (GET_OPCODE(i)) {
-    case OP_CALL:
-    case OP_TAILCALL:
-    case OP_RETURN:
-    case OP_SETLIST: {
-      check(GETARG_B(i) == 0);
-      return 1;
+/*
+** find a "name" for the RK value 'c'
+*/
+static void kname (lua_State *L, CallInfo *ci, int c, int oreg,
+                   const char *what, const char **name) {
+  if (ISK(c)) {  /* is 'c' a constant? */
+    TValue *kvalue = &ci_func(ci)->p->k[INDEXK(c)];
+    if (ttisstring(kvalue)) {  /* literal constant? */
+      *name = svalue(kvalue);  /* it is its own name */
+      return;
     }
-    default: return 0;  /* invalid instruction after an open call */
+    /* else no reasonable name found */
   }
-}
-
-
-static int checkArgMode (const Proto *pt, int r, enum OpArgMask mode) {
-  switch (mode) {
-    case OpArgN: check(r == 0); break;
-    case OpArgU: break;
-    case OpArgR: checkreg(pt, r); break;
-    case OpArgK:
-      check(ISK(r) ? INDEXK(r) < pt->sizek : r < pt->maxstacksize);
-      break;
+  else {  /* 'c' is a register */
+    if (c != oreg)  /* not the original register? */
+      what = getobjname(L, ci, c, name); /* search for 'c' */
+    if (what && *what == 'c') {  /* found a constant name? */
+      return;  /* 'name' already filled */
+    }
+    /* else no reasonable name found */
   }
-  return 1;
+  *name = "?";  /* no reasonable name found */
 }
 
 
-static Instruction symbexec (const Proto *pt, int lastpc, int reg) {
+static const char *getobjname (lua_State *L, CallInfo *ci, int reg,
+                               const char **name) {
+  Proto *p = ci_func(ci)->p;
+  const char *what = NULL;
+  int lastpc = currentpc(ci);
   int pc;
-  int last;  /* stores position of last instruction that changed `reg' */
-  last = pt->sizecode-1;  /* points to final return (a `neutral' instruction) */
-  check(precheck(pt));
+  *name = luaF_getlocalname(p, reg + 1, lastpc);
+  if (*name)  /* is a local? */
+    return "local";
+  /* else try symbolic execution */
   for (pc = 0; pc < lastpc; pc++) {
-    Instruction i = pt->code[pc];
+    Instruction i = p->code[pc];
     OpCode op = GET_OPCODE(i);
     int a = GETARG_A(i);
-    int b = 0;
-    int c = 0;
-    check(op < NUM_OPCODES);
-    checkreg(pt, a);
-    switch (getOpMode(op)) {
-      case iABC: {
-        b = GETARG_B(i);
-        c = GETARG_C(i);
-        check(checkArgMode(pt, b, getBMode(op)));
-        check(checkArgMode(pt, c, getCMode(op)));
+    switch (op) {
+      case OP_MOVE: {
+        if (reg == a) {
+          int b = GETARG_B(i);  /* move from 'b' to 'a' */
+          if (b < a)
+            what = getobjname(L, ci, b, name);  /* get name for 'b' */
+          else what = NULL;
+        }
         break;
       }
-      case iABx: {
-        b = GETARG_Bx(i);
-        if (getBMode(op) == OpArgK) check(b < pt->sizek);
+      case OP_GETTABUP:
+      case OP_GETTABLE: {
+        if (reg == a) {
+          int k = GETARG_C(i);  /* key index */
+          int t = GETARG_B(i);
+          const char *vn = (op == OP_GETTABLE)  /* name of indexed variable */
+                           ? luaF_getlocalname(p, t + 1, pc)
+                           : getstr(p->upvalues[t].name);
+          kname(L, ci, k, a, what, name);
+          what = (vn && strcmp(vn, LUA_ENV) == 0) ? "global" : "field";
+        }
         break;
       }
-      case iAsBx: {
-        b = GETARG_sBx(i);
-        if (getBMode(op) == OpArgR) {
-          int dest = pc+1+b;
-          check(0 <= dest && dest < pt->sizecode);
-          if (dest > 0) {
-            int j;
-            /* check that it does not jump to a setlist count; this
-               is tricky, because the count from a previous setlist may
-               have the same value of an invalid setlist; so, we must
-               go all the way back to the first of them (if any) */
-            for (j = 0; j < dest; j++) {
-              Instruction d = pt->code[dest-1-j];
-              if (!(GET_OPCODE(d) == OP_SETLIST && GETARG_C(d) == 0)) break;
-            }
-            /* if 'j' is even, previous value is not a setlist (even if
-               it looks like one) */
-            check((j&1) == 0);
-          }
+      case OP_GETUPVAL: {
+        if (reg == a) {
+          int u = GETARG_B(i);  /* upvalue index */
+          TString *tn = p->upvalues[u].name;
+          *name = tn ? getstr(tn) : "?";
+          what = "upvalue";
         }
         break;
       }
-    }
-    if (testAMode(op)) {
-      if (a == reg) last = pc;  /* change register `a' */
-    }
-    if (testTMode(op)) {
-      check(pc+2 < pt->sizecode);  /* check skip */
-      check(GET_OPCODE(pt->code[pc+1]) == OP_JMP);
-    }
-    switch (op) {
-      case OP_LOADBOOL: {
-        if (c == 1) {  /* does it jump? */
-          check(pc+2 < pt->sizecode);  /* check its jump */
-          check(GET_OPCODE(pt->code[pc+1]) != OP_SETLIST ||
-                GETARG_C(pt->code[pc+1]) != 0);
+      case OP_LOADK:
+      case OP_LOADKX: {
+        if (reg == a) {
+          int b = (op == OP_LOADK) ? GETARG_Bx(i)
+                                   : GETARG_Ax(p->code[pc + 1]);
+          if (ttisstring(&p->k[b])) {
+            what = "constant";
+            *name = svalue(&p->k[b]);
+          }
         }
         break;
       }
       case OP_LOADNIL: {
-        if (a <= reg && reg <= b)
-          last = pc;  /* set registers from `a' to `b' */
-        break;
-      }
-      case OP_GETUPVAL:
-      case OP_SETUPVAL: {
-        check(b < pt->nups);
-        break;
-      }
-      case OP_GETGLOBAL:
-      case OP_SETGLOBAL: {
-        check(ttisstring(&pt->k[b]));
+        int b = GETARG_B(i);
+        if (a <= reg && reg <= a + b)  /* set registers from 'a' to 'a+b' */
+          what = NULL;
         break;
       }
       case OP_SELF: {
-        checkreg(pt, a+1);
-        if (reg == a+1) last = pc;
-        break;
-      }
-      case OP_CONCAT: {
-        check(b < c);  /* at least two operands */
-        break;
-      }
-      case OP_TFORLOOP: {
-        check(c >= 1);  /* at least one result (control variable) */
-        checkreg(pt, a+2+c);  /* space for results */
-        if (reg >= a+2) last = pc;  /* affect all regs above its base */
+        if (reg == a) {
+          int k = GETARG_C(i);  /* key index */
+          kname(L, ci, k, a, what, name);
+          what = "method";
+        }
         break;
       }
-      case OP_FORLOOP:
-      case OP_FORPREP:
-        checkreg(pt, a+3);
-        /* go through */
-      case OP_JMP: {
-        int dest = pc+1+b;
-        /* not full check and jump is forward and do not skip `lastpc'? */
-        if (reg != NO_REG && pc < dest && dest <= lastpc)
-          pc += b;  /* do the jump */
+      case OP_TFORCALL: {
+        if (reg >= a + 2) what = NULL;  /* affect all regs above its base */
         break;
       }
       case OP_CALL:
       case OP_TAILCALL: {
-        if (b != 0) {
-          checkreg(pt, a+b-1);
-        }
-        c--;  /* c = num. returns */
-        if (c == LUA_MULTRET) {
-          check(checkopenop(pt, pc));
-        }
-        else if (c != 0)
-          checkreg(pt, a+c-1);
-        if (reg >= a) last = pc;  /* affect all registers above base */
-        break;
-      }
-      case OP_RETURN: {
-        b--;  /* b = num. returns */
-        if (b > 0) checkreg(pt, a+b-1);
+        if (reg >= a) what = NULL;  /* affect all registers above base */
         break;
       }
-      case OP_SETLIST: {
-        if (b > 0) checkreg(pt, a + b);
-        if (c == 0) {
-          pc++;
-          check(pc < pt->sizecode - 1);
-        }
+      case OP_JMP: {
+        int b = GETARG_sBx(i);
+        int dest = pc + 1 + b;
+        /* jump is forward and do not skip `lastpc'? */
+        if (pc < dest && dest <= lastpc)
+          pc += b;  /* do the jump */
         break;
       }
-      case OP_CLOSURE: {
-        int nup, j;
-        check(b < pt->sizep);
-        nup = pt->p[b]->nups;
-        check(pc + nup < pt->sizecode);
-        for (j = 1; j <= nup; j++) {
-          OpCode op1 = GET_OPCODE(pt->code[pc + j]);
-          check(op1 == OP_GETUPVAL || op1 == OP_MOVE);
-        }
-        if (reg != NO_REG)  /* tracing? */
-          pc += nup;  /* do not 'execute' these pseudo-instructions */
+      case OP_TEST: {
+        if (reg == a) what = NULL;  /* jumped code can change 'a' */
         break;
       }
-      case OP_VARARG: {
-        check((pt->is_vararg & VARARG_ISVARARG) &&
-             !(pt->is_vararg & VARARG_NEEDSARG));
-        b--;
-        if (b == LUA_MULTRET) check(checkopenop(pt, pc));
-        checkreg(pt, a+b-1);
+      default:
+        if (testAMode(op) && reg == a) what = NULL;
         break;
-      }
-      default: break;
     }
   }
-  return pt->code[last];
-}
-
-#undef check
-#undef checkjump
-#undef checkreg
-
-/* }====================================================== */
-
-
-int luaG_checkcode (const Proto *pt) {
-  return (symbexec(pt, pt->sizecode, NO_REG) != 0);
-}
-
-
-static const char *kname (Proto *p, int c) {
-  if (ISK(c) && ttisstring(&p->k[INDEXK(c)]))
-    return svalue(&p->k[INDEXK(c)]);
-  else
-    return "?";
+  return what;
 }
 
 
-static const char *getobjname (lua_State *L, CallInfo *ci, int stackpos,
-                               const char **name) {
-  if (isLua(ci)) {  /* a Lua function? */
-    Proto *p = ci_func(ci)->l.p;
-    int pc = currentpc(L, ci);
-    Instruction i;
-    *name = luaF_getlocalname(p, stackpos+1, pc);
-    if (*name)  /* is a local? */
-      return "local";
-    i = symbexec(p, pc, stackpos);  /* try symbolic execution */
-    lua_assert(pc != -1);
-    switch (GET_OPCODE(i)) {
-      case OP_GETGLOBAL: {
-        int g = GETARG_Bx(i);  /* global index */
-        lua_assert(ttisstring(&p->k[g]));
-        *name = svalue(&p->k[g]);
-        return "global";
-      }
-      case OP_MOVE: {
-        int a = GETARG_A(i);
-        int b = GETARG_B(i);  /* move from `b' to `a' */
-        if (b < a)
-          return getobjname(L, ci, b, name);  /* get name for `b' */
-        break;
-      }
-      case OP_GETTABLE: {
-        int k = GETARG_C(i);  /* key index */
-        *name = kname(p, k);
-        return "field";
-      }
-      case OP_GETUPVAL: {
-        int u = GETARG_B(i);  /* upvalue index */
-        *name = p->upvalues ? getstr(p->upvalues[u]) : "?";
-        return "upvalue";
-      }
-      case OP_SELF: {
-        int k = GETARG_C(i);  /* key index */
-        *name = kname(p, k);
-        return "method";
-      }
-      default: break;
+static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name) {
+  TMS tm;
+  Instruction i;
+  if ((ci->callstatus & CIST_TAIL) || !isLua(ci->previous))
+    return NULL;  /* calling function is not Lua (or is unknown) */
+  ci = ci->previous;  /* calling function */
+  i = ci_func(ci)->p->code[currentpc(ci)];
+  if (GET_OPCODE(i) == OP_EXTRAARG)  /* extra argument? */
+    i = ci_func(ci)->p->code[currentpc(ci) - 1];  /* get 'real' instruction */
+  switch (GET_OPCODE(i)) {
+    case OP_CALL:
+    case OP_TAILCALL:
+      return getobjname(L, ci, GETARG_A(i), name);
+    case OP_TFORCALL: {
+      *name = "for iterator";
+       return "for iterator";
     }
+    case OP_SELF:
+    case OP_GETTABUP:
+    case OP_GETTABLE: tm = TM_INDEX; break;
+    case OP_SETTABUP:
+    case OP_SETTABLE: tm = TM_NEWINDEX; break;
+    case OP_EQ: tm = TM_EQ; break;
+    case OP_ADD: tm = TM_ADD; break;
+    case OP_SUB: tm = TM_SUB; break;
+    case OP_MUL: tm = TM_MUL; break;
+    case OP_DIV: tm = TM_DIV; break;
+    case OP_MOD: tm = TM_MOD; break;
+    case OP_POW: tm = TM_POW; break;
+    case OP_UNM: tm = TM_UNM; break;
+    case OP_LEN: tm = TM_LEN; break;
+    case OP_LT: tm = TM_LT; break;
+    case OP_LE: tm = TM_LE; break;
+    case OP_CONCAT: tm = TM_CONCAT; break;
+    default:
+      return NULL;  /* else no useful name can be found */
   }
-  return NULL;  /* no useful name found */
+  *name = getstr(G(L)->tmname[tm]);
+  return "metamethod";
 }
 
+/* }====================================================== */
 
-static const char *getfuncname (lua_State *L, CallInfo *ci, const char **name) {
-  Instruction i;
-  if ((isLua(ci) && ci->tailcalls > 0) || !isLua(ci - 1))
-    return NULL;  /* calling function is not Lua (or is unknown) */
-  ci--;  /* calling function */
-  i = ci_func(ci)->l.p->code[currentpc(L, ci)];
-  if (GET_OPCODE(i) == OP_CALL || GET_OPCODE(i) == OP_TAILCALL ||
-      GET_OPCODE(i) == OP_TFORLOOP)
-    return getobjname(L, ci, GETARG_A(i), name);
-  else
-    return NULL;  /* no useful name can be found */
-}
 
 
-/* only ANSI way to check whether a pointer points to an array */
+/*
+** only ANSI way to check whether a pointer points to an array
+** (used only for error messages, so efficiency is not a big concern)
+*/
 static int isinstack (CallInfo *ci, const TValue *o) {
   StkId p;
-  for (p = ci->base; p < ci->top; p++)
+  for (p = ci->u.l.base; p < ci->top; p++)
     if (o == p) return 1;
   return 0;
 }
 
 
+static const char *getupvalname (CallInfo *ci, const TValue *o,
+                               const char **name) {
+  LClosure *c = ci_func(ci);
+  int i;
+  for (i = 0; i < c->nupvalues; i++) {
+    if (c->upvals[i]->v == o) {
+      *name = getstr(c->p->upvalues[i].name);
+      return "upvalue";
+    }
+  }
+  return NULL;
+}
+
+
 void luaG_typeerror (lua_State *L, const TValue *o, const char *op) {
+  CallInfo *ci = L->ci;
   const char *name = NULL;
-  const char *t = luaT_typenames[ttype(o)];
-  const char *kind = (isinstack(L->ci, o)) ?
-                         getobjname(L, L->ci, cast_int(o - L->base), &name) :
-                         NULL;
+  const char *t = objtypename(o);
+  const char *kind = NULL;
+  if (isLua(ci)) {
+    kind = getupvalname(ci, o, &name);  /* check whether 'o' is an upvalue */
+    if (!kind && isinstack(ci, o))  /* no? try a register */
+      kind = getobjname(L, ci, cast_int(o - ci->u.l.base), &name);
+  }
   if (kind)
     luaG_runerror(L, "attempt to %s %s " LUA_QS " (a %s value)",
                 op, kind, name, t);
@@ -580,7 +506,7 @@ void luaG_typeerror (lua_State *L, const TValue *o, const char *op) {
 
 void luaG_concaterror (lua_State *L, StkId p1, StkId p2) {
   if (ttisstring(p1) || ttisnumber(p1)) p1 = p2;
-  lua_assert(!ttisstring(p1) && !ttisnumber(p1));
+  lua_assert(!ttisstring(p1) && !ttisnumber(p2));
   luaG_typeerror(L, p1, "concatenate");
 }
 
@@ -594,9 +520,9 @@ void luaG_aritherror (lua_State *L, const TValue *p1, const TValue *p2) {
 
 
 int luaG_ordererror (lua_State *L, const TValue *p1, const TValue *p2) {
-  const char *t1 = luaT_typenames[ttype(p1)];
-  const char *t2 = luaT_typenames[ttype(p2)];
-  if (t1[2] == t2[2])
+  const char *t1 = objtypename(p1);
+  const char *t2 = objtypename(p2);
+  if (t1 == t2)
     luaG_runerror(L, "attempt to compare two %s values", t1);
   else
     luaG_runerror(L, "attempt to compare %s with %s", t1, t2);
@@ -608,8 +534,13 @@ static void addinfo (lua_State *L, const char *msg) {
   CallInfo *ci = L->ci;
   if (isLua(ci)) {  /* is Lua code? */
     char buff[LUA_IDSIZE];  /* add file:line information */
-    int line = currentline(L, ci);
-    luaO_chunkid(buff, getstr(getluaproto(ci)->source), LUA_IDSIZE);
+    int line = currentline(ci);
+    TString *src = ci_func(ci)->p->source;
+    if (src)
+      luaO_chunkid(buff, getstr(src), LUA_IDSIZE);
+    else {  /* no source available; use "?" instead */
+      buff[0] = '?'; buff[1] = '\0';
+    }
     luaO_pushfstring(L, "%s:%d: %s", buff, line, msg);
   }
 }
@@ -622,7 +553,7 @@ void luaG_errormsg (lua_State *L) {
     setobjs2s(L, L->top, L->top - 1);  /* move argument */
     setobjs2s(L, L->top - 1, errfunc);  /* push function */
     incr_top(L);
-    luaD_call(L, L->top - 2, 1);  /* call it */
+    luaD_call(L, L->top - 2, 1, 0);  /* call it */
   }
   luaD_throw(L, LUA_ERRRUN);
 }
diff --git a/src/ldebug.h b/src/ldebug.h
index ba28a97..6590c56 100644..100755
--- a/src/ldebug.h
+++ b/src/ldebug.h
@@ -1,5 +1,5 @@
 /*
-** $Id: ldebug.h,v 2.3.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: ldebug.h,v 2.6 2011/06/02 19:31:40 roberto Exp $
 ** Auxiliary functions from Debug Interface module
 ** See Copyright Notice in lua.h
 */
@@ -13,10 +13,13 @@
 
 #define pcRel(pc, p)	(cast(int, (pc) - (p)->code) - 1)
 
-#define getline(f,pc)	(((f)->lineinfo) ? (f)->lineinfo[pc] : 0)
+#define getfuncline(f,pc)	(((f)->lineinfo) ? (f)->lineinfo[pc] : 0)
 
 #define resethookcount(L)	(L->hookcount = L->basehookcount)
 
+/* Active Lua function (given call info) */
+#define ci_func(ci)		(clLvalue((ci)->func))
+
 
 LUAI_FUNC void luaG_typeerror (lua_State *L, const TValue *o,
                                              const char *opname);
@@ -27,7 +30,5 @@ LUAI_FUNC int luaG_ordererror (lua_State *L, const TValue *p1,
                                              const TValue *p2);
 LUAI_FUNC void luaG_runerror (lua_State *L, const char *fmt, ...);
 LUAI_FUNC void luaG_errormsg (lua_State *L);
-LUAI_FUNC int luaG_checkcode (const Proto *pt);
-LUAI_FUNC int luaG_checkopenop (Instruction i);
 
 #endif
diff --git a/src/ldo.c b/src/ldo.c
index 8de05f7..a34b0d0 100644..100755
--- a/src/ldo.c
+++ b/src/ldo.c
@@ -1,5 +1,5 @@
 /*
-** $Id: ldo.c,v 2.38.1.3 2008/01/18 22:31:22 roberto Exp $
+** $Id: ldo.c,v 2.98 2011/06/28 15:42:04 roberto Exp $
 ** Stack and Call structure of Lua
 ** See Copyright Notice in lua.h
 */
@@ -14,6 +14,7 @@
 
 #include "lua.h"
 
+#include "lapi.h"
 #include "ldebug.h"
 #include "ldo.h"
 #include "lfunc.h"
@@ -39,6 +40,38 @@
 ** =======================================================
 */
 
+/*
+** LUAI_THROW/LUAI_TRY define how Lua does exception handling. By
+** default, Lua handles errors with exceptions when compiling as
+** C++ code, with _longjmp/_setjmp when asked to use them, and with
+** longjmp/setjmp otherwise.
+*/
+#if !defined(LUAI_THROW)
+
+#if defined(__cplusplus) && !defined(LUA_USE_LONGJMP)
+/* C++ exceptions */
+#define LUAI_THROW(L,c)		throw(c)
+#define LUAI_TRY(L,c,a) \
+	try { a } catch(...) { if ((c)->status == 0) (c)->status = -1; }
+#define luai_jmpbuf		int  /* dummy variable */
+
+#elif defined(LUA_USE_ULONGJMP)
+/* in Unix, try _longjmp/_setjmp (more efficient) */
+#define LUAI_THROW(L,c)		_longjmp((c)->b, 1)
+#define LUAI_TRY(L,c,a)		if (_setjmp((c)->b) == 0) { a }
+#define luai_jmpbuf		jmp_buf
+
+#else
+/* default handling with long jumps */
+#define LUAI_THROW(L,c)		longjmp((c)->b, 1)
+#define LUAI_TRY(L,c,a)		if (setjmp((c)->b) == 0) { a }
+#define luai_jmpbuf		jmp_buf
+
+#endif
+
+#endif
+
+
 
 /* chain list of long jump buffers */
 struct lua_longjmp {
@@ -48,18 +81,17 @@ struct lua_longjmp {
 };
 
 
-void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop) {
+static void seterrorobj (lua_State *L, int errcode, StkId oldtop) {
   switch (errcode) {
-    case LUA_ERRMEM: {
-      setsvalue2s(L, oldtop, luaS_newliteral(L, MEMERRMSG));
+    case LUA_ERRMEM: {  /* memory error? */
+      setsvalue2s(L, oldtop, G(L)->memerrmsg); /* reuse preregistered msg. */
       break;
     }
     case LUA_ERRERR: {
       setsvalue2s(L, oldtop, luaS_newliteral(L, "error in error handling"));
       break;
     }
-    case LUA_ERRSYNTAX:
-    case LUA_ERRRUN: {
+    default: {
       setobjs2s(L, oldtop, L->top - 1);  /* error message on current top */
       break;
     }
@@ -68,55 +100,39 @@ void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop) {
 }
 
 
-static void restore_stack_limit (lua_State *L) {
-  lua_assert(L->stack_last - L->stack == L->stacksize - EXTRA_STACK - 1);
-  if (L->size_ci > LUAI_MAXCALLS) {  /* there was an overflow? */
-    int inuse = cast_int(L->ci - L->base_ci);
-    if (inuse + 1 < LUAI_MAXCALLS)  /* can `undo' overflow? */
-      luaD_reallocCI(L, LUAI_MAXCALLS);
-  }
-}
-
-
-static void resetstack (lua_State *L, int status) {
-  L->ci = L->base_ci;
-  L->base = L->ci->base;
-  luaF_close(L, L->base);  /* close eventual pending closures */
-  luaD_seterrorobj(L, status, L->base);
-  L->nCcalls = L->baseCcalls;
-  L->allowhook = 1;
-  restore_stack_limit(L);
-  L->errfunc = 0;
-  L->errorJmp = NULL;
-}
-
-
 void luaD_throw (lua_State *L, int errcode) {
-  if (L->errorJmp) {
-    L->errorJmp->status = errcode;
-    LUAI_THROW(L, L->errorJmp);
+  if (L->errorJmp) {  /* thread has an error handler? */
+    L->errorJmp->status = errcode;  /* set status */
+    LUAI_THROW(L, L->errorJmp);  /* jump to it */
   }
-  else {
-    L->status = cast_byte(errcode);
-    if (G(L)->panic) {
-      resetstack(L, errcode);
-      lua_unlock(L);
-      G(L)->panic(L);
+  else {  /* thread has no error handler */
+    L->status = cast_byte(errcode);  /* mark it as dead */
+    if (G(L)->mainthread->errorJmp) {  /* main thread has a handler? */
+      setobjs2s(L, G(L)->mainthread->top++, L->top - 1);  /* copy error obj. */
+      luaD_throw(G(L)->mainthread, errcode);  /* re-throw in main thread */
+    }
+    else {  /* no handler at all; abort */
+      if (G(L)->panic) {  /* panic function? */
+        lua_unlock(L);
+        G(L)->panic(L);  /* call it (last chance to jump out) */
+      }
+      abort();
     }
-    exit(EXIT_FAILURE);
   }
 }
 
 
 int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud) {
+  unsigned short oldnCcalls = G(L)->nCcalls;
   struct lua_longjmp lj;
-  lj.status = 0;
+  lj.status = LUA_OK;
   lj.previous = L->errorJmp;  /* chain new error handler */
   L->errorJmp = &lj;
   LUAI_TRY(L, &lj,
     (*f)(L, ud);
   );
   L->errorJmp = lj.previous;  /* restore old error handler */
+  G(L)->nCcalls = oldnCcalls;
   return lj.status;
 }
 
@@ -129,112 +145,126 @@ static void correctstack (lua_State *L, TValue *oldstack) {
   L->top = (L->top - oldstack) + L->stack;
   for (up = L->openupval; up != NULL; up = up->gch.next)
     gco2uv(up)->v = (gco2uv(up)->v - oldstack) + L->stack;
-  for (ci = L->base_ci; ci <= L->ci; ci++) {
+  for (ci = L->ci; ci != NULL; ci = ci->previous) {
     ci->top = (ci->top - oldstack) + L->stack;
-    ci->base = (ci->base - oldstack) + L->stack;
     ci->func = (ci->func - oldstack) + L->stack;
+    if (isLua(ci))
+      ci->u.l.base = (ci->u.l.base - oldstack) + L->stack;
   }
-  L->base = (L->base - oldstack) + L->stack;
 }
 
 
+/* some space for error handling */
+#define ERRORSTACKSIZE	(LUAI_MAXSTACK + 200)
+
+
 void luaD_reallocstack (lua_State *L, int newsize) {
   TValue *oldstack = L->stack;
-  int realsize = newsize + 1 + EXTRA_STACK;
-  lua_assert(L->stack_last - L->stack == L->stacksize - EXTRA_STACK - 1);
-  luaM_reallocvector(L, L->stack, L->stacksize, realsize, TValue);
-  L->stacksize = realsize;
-  L->stack_last = L->stack+newsize;
+  int lim = L->stacksize;
+  lua_assert(newsize <= LUAI_MAXSTACK || newsize == ERRORSTACKSIZE);
+  lua_assert(L->stack_last - L->stack == L->stacksize - EXTRA_STACK);
+  luaM_reallocvector(L, L->stack, L->stacksize, newsize, TValue);
+  for (; lim < newsize; lim++)
+    setnilvalue(L->stack + lim); /* erase new segment */
+  L->stacksize = newsize;
+  L->stack_last = L->stack + newsize - EXTRA_STACK;
   correctstack(L, oldstack);
 }
 
 
-void luaD_reallocCI (lua_State *L, int newsize) {
-  CallInfo *oldci = L->base_ci;
-  luaM_reallocvector(L, L->base_ci, L->size_ci, newsize, CallInfo);
-  L->size_ci = newsize;
-  L->ci = (L->ci - oldci) + L->base_ci;
-  L->end_ci = L->base_ci + L->size_ci - 1;
+void luaD_growstack (lua_State *L, int n) {
+  int size = L->stacksize;
+  if (size > LUAI_MAXSTACK)  /* error after extra size? */
+    luaD_throw(L, LUA_ERRERR);
+  else {
+    int needed = cast_int(L->top - L->stack) + n + EXTRA_STACK;
+    int newsize = 2 * size;
+    if (newsize > LUAI_MAXSTACK) newsize = LUAI_MAXSTACK;
+    if (newsize < needed) newsize = needed;
+    if (newsize > LUAI_MAXSTACK) {  /* stack overflow? */
+      luaD_reallocstack(L, ERRORSTACKSIZE);
+      luaG_runerror(L, "stack overflow");
+    }
+    else
+      luaD_reallocstack(L, newsize);
+  }
 }
 
 
-void luaD_growstack (lua_State *L, int n) {
-  if (n <= L->stacksize)  /* double size is enough? */
-    luaD_reallocstack(L, 2*L->stacksize);
-  else
-    luaD_reallocstack(L, L->stacksize + n);
+static int stackinuse (lua_State *L) {
+  CallInfo *ci;
+  StkId lim = L->top;
+  for (ci = L->ci; ci != NULL; ci = ci->previous) {
+    lua_assert(ci->top <= L->stack_last);
+    if (lim < ci->top) lim = ci->top;
+  }
+  return cast_int(lim - L->stack) + 1;  /* part of stack in use */
 }
 
 
-static CallInfo *growCI (lua_State *L) {
-  if (L->size_ci > LUAI_MAXCALLS)  /* overflow while handling overflow? */
-    luaD_throw(L, LUA_ERRERR);
-  else {
-    luaD_reallocCI(L, 2*L->size_ci);
-    if (L->size_ci > LUAI_MAXCALLS)
-      luaG_runerror(L, "stack overflow");
-  }
-  return ++L->ci;
+void luaD_shrinkstack (lua_State *L) {
+  int inuse = stackinuse(L);
+  int goodsize = inuse + (inuse / 8) + 2*EXTRA_STACK;
+  if (goodsize > LUAI_MAXSTACK) goodsize = LUAI_MAXSTACK;
+  if (inuse > LUAI_MAXSTACK ||  /* handling stack overflow? */
+      goodsize >= L->stacksize)  /* would grow instead of shrink? */
+    condmovestack(L);  /* don't change stack (change only for debugging) */
+  else
+    luaD_reallocstack(L, goodsize);  /* shrink it */
 }
 
 
-void luaD_callhook (lua_State *L, int event, int line) {
+void luaD_hook (lua_State *L, int event, int line) {
   lua_Hook hook = L->hook;
   if (hook && L->allowhook) {
+    CallInfo *ci = L->ci;
     ptrdiff_t top = savestack(L, L->top);
-    ptrdiff_t ci_top = savestack(L, L->ci->top);
+    ptrdiff_t ci_top = savestack(L, ci->top);
     lua_Debug ar;
     ar.event = event;
     ar.currentline = line;
-    if (event == LUA_HOOKTAILRET)
-      ar.i_ci = 0;  /* tail call; no debug information about it */
-    else
-      ar.i_ci = cast_int(L->ci - L->base_ci);
+    ar.i_ci = ci;
     luaD_checkstack(L, LUA_MINSTACK);  /* ensure minimum stack size */
-    L->ci->top = L->top + LUA_MINSTACK;
-    lua_assert(L->ci->top <= L->stack_last);
+    ci->top = L->top + LUA_MINSTACK;
+    lua_assert(ci->top <= L->stack_last);
     L->allowhook = 0;  /* cannot call hooks inside a hook */
+    ci->callstatus |= CIST_HOOKED;
     lua_unlock(L);
     (*hook)(L, &ar);
     lua_lock(L);
     lua_assert(!L->allowhook);
     L->allowhook = 1;
-    L->ci->top = restorestack(L, ci_top);
+    ci->top = restorestack(L, ci_top);
     L->top = restorestack(L, top);
+    ci->callstatus &= ~CIST_HOOKED;
   }
 }
 
 
+static void callhook (lua_State *L, CallInfo *ci) {
+  int hook = LUA_HOOKCALL;
+  ci->u.l.savedpc++;  /* hooks assume 'pc' is already incremented */
+  if (isLua(ci->previous) &&
+      GET_OPCODE(*(ci->previous->u.l.savedpc - 1)) == OP_TAILCALL) {
+    ci->callstatus |= CIST_TAIL;
+    hook = LUA_HOOKTAILCALL;
+  }
+  luaD_hook(L, hook, -1);
+  ci->u.l.savedpc--;  /* correct 'pc' */
+}
+
+
 static StkId adjust_varargs (lua_State *L, Proto *p, int actual) {
   int i;
   int nfixargs = p->numparams;
-  Table *htab = NULL;
   StkId base, fixed;
-  for (; actual < nfixargs; ++actual)
-    setnilvalue(L->top++);
-#if defined(LUA_COMPAT_VARARG)
-  if (p->is_vararg & VARARG_NEEDSARG) { /* compat. with old-style vararg? */
-    int nvar = actual - nfixargs;  /* number of extra arguments */
-    lua_assert(p->is_vararg & VARARG_HASARG);
-    luaC_checkGC(L);
-    htab = luaH_new(L, nvar, 1);  /* create `arg' table */
-    for (i=0; i<nvar; i++)  /* put extra arguments into `arg' table */
-      setobj2n(L, luaH_setnum(L, htab, i+1), L->top - nvar + i);
-    /* store counter in field `n' */
-    setnvalue(luaH_setstr(L, htab, luaS_newliteral(L, "n")), cast_num(nvar));
-  }
-#endif
+  lua_assert(actual >= nfixargs);
   /* move fixed parameters to final position */
   fixed = L->top - actual;  /* first fixed argument */
   base = L->top;  /* final position of first argument */
   for (i=0; i<nfixargs; i++) {
-    setobjs2s(L, L->top++, fixed+i);
-    setnilvalue(fixed+i);
-  }
-  /* add `arg' parameter */
-  if (htab) {
-    sethvalue(L, L->top++, htab);
-    lua_assert(iswhite(obj2gco(htab)));
+    setobjs2s(L, L->top++, fixed + i);
+    setnilvalue(fixed + i);
   }
   return base;
 }
@@ -256,100 +286,85 @@ static StkId tryfuncTM (lua_State *L, StkId func) {
 
 
 
-#define inc_ci(L) \
-  ((L->ci == L->end_ci) ? growCI(L) : \
-   (condhardstacktests(luaD_reallocCI(L, L->size_ci)), ++L->ci))
+#define next_ci(L) (L->ci = (L->ci->next ? L->ci->next : luaE_extendCI(L)))
 
 
+/*
+** returns true if function has been executed (C function)
+*/
 int luaD_precall (lua_State *L, StkId func, int nresults) {
-  LClosure *cl;
-  ptrdiff_t funcr;
-  if (!ttisfunction(func)) /* `func' is not a function? */
-    func = tryfuncTM(L, func);  /* check the `function' tag method */
-  funcr = savestack(L, func);
-  cl = &clvalue(func)->l;
-  L->ci->savedpc = L->savedpc;
-  if (!cl->isC) {  /* Lua function? prepare its call */
-    CallInfo *ci;
-    StkId st, base;
-    Proto *p = cl->p;
-    luaD_checkstack(L, p->maxstacksize);
-    func = restorestack(L, funcr);
-    if (!p->is_vararg) {  /* no varargs? */
-      base = func + 1;
-      if (L->top > base + p->numparams)
-        L->top = base + p->numparams;
+  lua_CFunction f;
+  CallInfo *ci;
+  int n;  /* number of arguments (Lua) or returns (C) */
+  ptrdiff_t funcr = savestack(L, func);
+  switch (ttype(func)) {
+    case LUA_TLCF:  /* light C function */
+      f = fvalue(func);
+      goto Cfunc;
+    case LUA_TCCL: {  /* C closure */
+      f = clCvalue(func)->f;
+     Cfunc:
+      luaD_checkstack(L, LUA_MINSTACK);  /* ensure minimum stack size */
+      ci = next_ci(L);  /* now 'enter' new function */
+      ci->nresults = nresults;
+      ci->func = restorestack(L, funcr);
+      ci->top = L->top + LUA_MINSTACK;
+      lua_assert(ci->top <= L->stack_last);
+      ci->callstatus = 0;
+      if (L->hookmask & LUA_MASKCALL)
+        luaD_hook(L, LUA_HOOKCALL, -1);
+      lua_unlock(L);
+      n = (*f)(L);  /* do the actual call */
+      lua_lock(L);
+      api_checknelems(L, n);
+      luaD_poscall(L, L->top - n);
+      return 1;
     }
-    else {  /* vararg function */
-      int nargs = cast_int(L->top - func) - 1;
-      base = adjust_varargs(L, p, nargs);
-      func = restorestack(L, funcr);  /* previous call may change the stack */
+    case LUA_TLCL: {  /* Lua function: prepare its call */
+      StkId base;
+      Proto *p = clLvalue(func)->p;
+      luaD_checkstack(L, p->maxstacksize);
+      func = restorestack(L, funcr);
+      n = cast_int(L->top - func) - 1;  /* number of real arguments */
+      for (; n < p->numparams; n++)
+        setnilvalue(L->top++);  /* complete missing arguments */
+      base = (!p->is_vararg) ? func + 1 : adjust_varargs(L, p, n);
+      ci = next_ci(L);  /* now 'enter' new function */
+      ci->nresults = nresults;
+      ci->func = func;
+      ci->u.l.base = base;
+      ci->top = base + p->maxstacksize;
+      lua_assert(ci->top <= L->stack_last);
+      ci->u.l.savedpc = p->code;  /* starting point */
+      ci->callstatus = CIST_LUA;
+      L->top = ci->top;
+      if (L->hookmask & LUA_MASKCALL)
+        callhook(L, ci);
+      return 0;
     }
-    ci = inc_ci(L);  /* now `enter' new function */
-    ci->func = func;
-    L->base = ci->base = base;
-    ci->top = L->base + p->maxstacksize;
-    lua_assert(ci->top <= L->stack_last);
-    L->savedpc = p->code;  /* starting point */
-    ci->tailcalls = 0;
-    ci->nresults = nresults;
-    for (st = L->top; st < ci->top; st++)
-      setnilvalue(st);
-    L->top = ci->top;
-    if (L->hookmask & LUA_MASKCALL) {
-      L->savedpc++;  /* hooks assume 'pc' is already incremented */
-      luaD_callhook(L, LUA_HOOKCALL, -1);
-      L->savedpc--;  /* correct 'pc' */
+    default: {  /* not a function */
+      func = tryfuncTM(L, func);  /* retry with 'function' tag method */
+      return luaD_precall(L, func, nresults);
     }
-    return PCRLUA;
   }
-  else {  /* if is a C function, call it */
-    CallInfo *ci;
-    int n;
-    luaD_checkstack(L, LUA_MINSTACK);  /* ensure minimum stack size */
-    ci = inc_ci(L);  /* now `enter' new function */
-    ci->func = restorestack(L, funcr);
-    L->base = ci->base = ci->func + 1;
-    ci->top = L->top + LUA_MINSTACK;
-    lua_assert(ci->top <= L->stack_last);
-    ci->nresults = nresults;
-    if (L->hookmask & LUA_MASKCALL)
-      luaD_callhook(L, LUA_HOOKCALL, -1);
-    lua_unlock(L);
-    n = (*curr_func(L)->c.f)(L);  /* do the actual call */
-    lua_lock(L);
-    if (n < 0)  /* yielding? */
-      return PCRYIELD;
-    else {
-      luaD_poscall(L, L->top - n);
-      return PCRC;
-    }
-  }
-}
-
-
-static StkId callrethooks (lua_State *L, StkId firstResult) {
-  ptrdiff_t fr = savestack(L, firstResult);  /* next call may change stack */
-  luaD_callhook(L, LUA_HOOKRET, -1);
-  if (f_isLua(L->ci)) {  /* Lua function? */
-    while ((L->hookmask & LUA_MASKRET) && L->ci->tailcalls--) /* tail calls */
-      luaD_callhook(L, LUA_HOOKTAILRET, -1);
-  }
-  return restorestack(L, fr);
 }
 
 
 int luaD_poscall (lua_State *L, StkId firstResult) {
   StkId res;
   int wanted, i;
-  CallInfo *ci;
-  if (L->hookmask & LUA_MASKRET)
-    firstResult = callrethooks(L, firstResult);
-  ci = L->ci--;
+  CallInfo *ci = L->ci;
+  if (L->hookmask & (LUA_MASKRET | LUA_MASKLINE)) {
+    if (L->hookmask & LUA_MASKRET) {
+      ptrdiff_t fr = savestack(L, firstResult);  /* hook may change stack */
+      luaD_hook(L, LUA_HOOKRET, -1);
+      firstResult = restorestack(L, fr);
+    }
+    L->oldpc = ci->previous->u.l.savedpc;  /* 'oldpc' for caller function */
+  }
   res = ci->func;  /* res == final position of 1st result */
   wanted = ci->nresults;
-  L->base = (ci - 1)->base;  /* restore base */
-  L->savedpc = (ci - 1)->savedpc;  /* restore savedpc */
+  L->ci = ci = ci->previous;  /* back to caller */
   /* move results to correct place */
   for (i = wanted; i != 0 && firstResult < L->top; i--)
     setobjs2s(L, res++, firstResult++);
@@ -365,112 +380,223 @@ int luaD_poscall (lua_State *L, StkId firstResult) {
 ** The arguments are on the stack, right after the function.
 ** When returns, all the results are on the stack, starting at the original
 ** function position.
-*/ 
-void luaD_call (lua_State *L, StkId func, int nResults) {
-  if (++L->nCcalls >= LUAI_MAXCCALLS) {
-    if (L->nCcalls == LUAI_MAXCCALLS)
+*/
+void luaD_call (lua_State *L, StkId func, int nResults, int allowyield) {
+  global_State *g = G(L);
+  if (++g->nCcalls >= LUAI_MAXCCALLS) {
+    if (g->nCcalls == LUAI_MAXCCALLS)
       luaG_runerror(L, "C stack overflow");
-    else if (L->nCcalls >= (LUAI_MAXCCALLS + (LUAI_MAXCCALLS>>3)))
+    else if (g->nCcalls >= (LUAI_MAXCCALLS + (LUAI_MAXCCALLS>>3)))
       luaD_throw(L, LUA_ERRERR);  /* error while handing stack error */
   }
-  if (luaD_precall(L, func, nResults) == PCRLUA)  /* is a Lua function? */
-    luaV_execute(L, 1);  /* call it */
-  L->nCcalls--;
+  if (!allowyield) L->nny++;
+  if (!luaD_precall(L, func, nResults))  /* is a Lua function? */
+    luaV_execute(L);  /* call it */
+  if (!allowyield) L->nny--;
+  g->nCcalls--;
   luaC_checkGC(L);
 }
 
 
-static void resume (lua_State *L, void *ud) {
-  StkId firstArg = cast(StkId, ud);
+static void finishCcall (lua_State *L) {
   CallInfo *ci = L->ci;
-  if (L->status == 0) {  /* start coroutine? */
-    lua_assert(ci == L->base_ci && firstArg > L->base);
-    if (luaD_precall(L, firstArg - 1, LUA_MULTRET) != PCRLUA)
-      return;
-  }
-  else {  /* resuming from previous yield */
-    lua_assert(L->status == LUA_YIELD);
-    L->status = 0;
-    if (!f_isLua(ci)) {  /* `common' yield? */
-      /* finish interrupted execution of `OP_CALL' */
-      lua_assert(GET_OPCODE(*((ci-1)->savedpc - 1)) == OP_CALL ||
-                 GET_OPCODE(*((ci-1)->savedpc - 1)) == OP_TAILCALL);
-      if (luaD_poscall(L, firstArg))  /* complete it... */
-        L->top = L->ci->top;  /* and correct top if not multiple results */
+  int n;
+  lua_assert(ci->u.c.k != NULL);  /* must have a continuation */
+  lua_assert(L->nny == 0);
+  /* finish 'luaD_call' */
+  G(L)->nCcalls--;
+  /* finish 'lua_callk' */
+  adjustresults(L, ci->nresults);
+  /* call continuation function */
+  if (!(ci->callstatus & CIST_STAT))  /* no call status? */
+    ci->u.c.status = LUA_YIELD;  /* 'default' status */
+  lua_assert(ci->u.c.status != LUA_OK);
+  ci->callstatus = (ci->callstatus & ~(CIST_YPCALL | CIST_STAT)) | CIST_YIELDED;
+  lua_unlock(L);
+  n = (*ci->u.c.k)(L);
+  lua_lock(L);
+  api_checknelems(L, n);
+  /* finish 'luaD_precall' */
+  luaD_poscall(L, L->top - n);
+}
+
+
+static void unroll (lua_State *L, void *ud) {
+  UNUSED(ud);
+  for (;;) {
+    if (L->ci == &L->base_ci)  /* stack is empty? */
+      return;  /* coroutine finished normally */
+    if (!isLua(L->ci))  /* C function? */
+      finishCcall(L);
+    else {  /* Lua function */
+      luaV_finishOp(L);  /* finish interrupted instruction */
+      luaV_execute(L);  /* execute down to higher C 'boundary' */
     }
-    else  /* yielded inside a hook: just continue its execution */
-      L->base = L->ci->base;
   }
-  luaV_execute(L, cast_int(L->ci - L->base_ci));
 }
 
 
-static int resume_error (lua_State *L, const char *msg) {
-  L->top = L->ci->base;
-  setsvalue2s(L, L->top, luaS_new(L, msg));
+/*
+** check whether thread has a suspended protected call
+*/
+static CallInfo *findpcall (lua_State *L) {
+  CallInfo *ci;
+  for (ci = L->ci; ci != NULL; ci = ci->previous) {  /* search for a pcall */
+    if (ci->callstatus & CIST_YPCALL)
+      return ci;
+  }
+  return NULL;  /* no pending pcall */
+}
+
+
+static int recover (lua_State *L, int status) {
+  StkId oldtop;
+  CallInfo *ci = findpcall(L);
+  if (ci == NULL) return 0;  /* no recovery point */
+  /* "finish" luaD_pcall */
+  oldtop = restorestack(L, ci->u.c.extra);
+  luaF_close(L, oldtop);
+  seterrorobj(L, status, oldtop);
+  L->ci = ci;
+  L->allowhook = ci->u.c.old_allowhook;
+  L->nny = 0;  /* should be zero to be yieldable */
+  luaD_shrinkstack(L);
+  L->errfunc = ci->u.c.old_errfunc;
+  ci->callstatus |= CIST_STAT;  /* call has error status */
+  ci->u.c.status = status;  /* (here it is) */
+  return 1;  /* continue running the coroutine */
+}
+
+
+/*
+** signal an error in the call to 'resume', not in the execution of the
+** coroutine itself. (Such errors should not be handled by any coroutine
+** error handler and should not kill the coroutine.)
+*/
+static void resume_error (lua_State *L, const char *msg, StkId firstArg) {
+  L->top = firstArg;  /* remove args from the stack */
+  setsvalue2s(L, L->top, luaS_new(L, msg));  /* push error message */
   incr_top(L);
-  lua_unlock(L);
-  return LUA_ERRRUN;
+  luaD_throw(L, -1);  /* jump back to 'lua_resume' */
+}
+
+
+/*
+** do the work for 'lua_resume' in protected mode
+*/
+static void resume (lua_State *L, void *ud) {
+  StkId firstArg = cast(StkId, ud);
+  CallInfo *ci = L->ci;
+  if (G(L)->nCcalls >= LUAI_MAXCCALLS)
+    resume_error(L, "C stack overflow", firstArg);
+  if (L->status == LUA_OK) {  /* may be starting a coroutine */
+    if (ci != &L->base_ci)  /* not in base level? */
+      resume_error(L, "cannot resume non-suspended coroutine", firstArg);
+    /* coroutine is in base level; start running it */
+    if (!luaD_precall(L, firstArg - 1, LUA_MULTRET))  /* Lua function? */
+      luaV_execute(L);  /* call it */
+  }
+  else if (L->status != LUA_YIELD)
+    resume_error(L, "cannot resume dead coroutine", firstArg);
+  else {  /* resuming from previous yield */
+    L->status = LUA_OK;
+    if (isLua(ci))  /* yielded inside a hook? */
+      luaV_execute(L);  /* just continue running Lua code */
+    else {  /* 'common' yield */
+      ci->func = restorestack(L, ci->u.c.extra);
+      if (ci->u.c.k != NULL) {  /* does it have a continuation? */
+        int n;
+        ci->u.c.status = LUA_YIELD;  /* 'default' status */
+        ci->callstatus |= CIST_YIELDED;
+        lua_unlock(L);
+        n = (*ci->u.c.k)(L);  /* call continuation */
+        lua_lock(L);
+        api_checknelems(L, n);
+        firstArg = L->top - n;  /* yield results come from continuation */
+      }
+      G(L)->nCcalls--;  /* finish 'luaD_call' */
+      luaD_poscall(L, firstArg);  /* finish 'luaD_precall' */
+    }
+    unroll(L, NULL);
+  }
 }
 
 
 LUA_API int lua_resume (lua_State *L, int nargs) {
   int status;
   lua_lock(L);
-  if (L->status != LUA_YIELD && (L->status != 0 || L->ci != L->base_ci))
-      return resume_error(L, "cannot resume non-suspended coroutine");
-  if (L->nCcalls >= LUAI_MAXCCALLS)
-    return resume_error(L, "C stack overflow");
   luai_userstateresume(L, nargs);
-  lua_assert(L->errfunc == 0);
-  L->baseCcalls = ++L->nCcalls;
+  ++G(L)->nCcalls;  /* count resume */
+  L->nny = 0;  /* allow yields */
+  api_checknelems(L, (L->status == LUA_OK) ? nargs + 1 : nargs);
   status = luaD_rawrunprotected(L, resume, L->top - nargs);
-  if (status != 0) {  /* error? */
-    L->status = cast_byte(status);  /* mark thread as `dead' */
-    luaD_seterrorobj(L, status, L->top);
-    L->ci->top = L->top;
-  }
-  else {
-    lua_assert(L->nCcalls == L->baseCcalls);
-    status = L->status;
+  if (status == -1)  /* error calling 'lua_resume'? */
+    status = LUA_ERRRUN;
+  else {  /* yield or regular error */
+    while (status != LUA_OK && status != LUA_YIELD) {  /* error? */
+      if (recover(L, status))  /* recover point? */
+        status = luaD_rawrunprotected(L, unroll, NULL);  /* run continuation */
+      else {  /* unrecoverable error */
+        L->status = cast_byte(status);  /* mark thread as `dead' */
+        seterrorobj(L, status, L->top);
+        L->ci->top = L->top;
+        break;
+      }
+    }
+    lua_assert(status == L->status);
   }
-  --L->nCcalls;
+  L->nny = 1;  /* do not allow yields */
+  --G(L)->nCcalls;
   lua_unlock(L);
   return status;
 }
 
 
-LUA_API int lua_yield (lua_State *L, int nresults) {
+LUA_API int lua_yieldk (lua_State *L, int nresults, int ctx, lua_CFunction k) {
+  CallInfo *ci = L->ci;
   luai_userstateyield(L, nresults);
   lua_lock(L);
-  if (L->nCcalls > L->baseCcalls)
-    luaG_runerror(L, "attempt to yield across metamethod/C-call boundary");
-  L->base = L->top - nresults;  /* protect stack slots below */
+  api_checknelems(L, nresults);
+  if (L->nny > 0) {
+    if (L != G(L)->mainthread)
+      luaG_runerror(L, "attempt to yield across metamethod/C-call boundary");
+    else
+      luaG_runerror(L, "attempt to yield from outside a coroutine");
+  }
   L->status = LUA_YIELD;
+  if (isLua(ci)) {  /* inside a hook? */
+    api_check(L, k == NULL, "hooks cannot continue after yielding");
+  }
+  else {
+    if ((ci->u.c.k = k) != NULL)  /* is there a continuation? */
+      ci->u.c.ctx = ctx;  /* save context */
+    ci->u.c.extra = savestack(L, ci->func);  /* save current 'func' */
+    ci->func = L->top - nresults - 1;  /* protect stack below results */
+    luaD_throw(L, LUA_YIELD);
+  }
+  lua_assert(ci->callstatus & CIST_HOOKED);  /* must be inside a hook */
   lua_unlock(L);
-  return -1;
+  return 0;  /* return to 'luaD_hook' */
 }
 
 
 int luaD_pcall (lua_State *L, Pfunc func, void *u,
                 ptrdiff_t old_top, ptrdiff_t ef) {
   int status;
-  unsigned short oldnCcalls = L->nCcalls;
-  ptrdiff_t old_ci = saveci(L, L->ci);
+  CallInfo *old_ci = L->ci;
   lu_byte old_allowhooks = L->allowhook;
+  unsigned short old_nny = L->nny;
   ptrdiff_t old_errfunc = L->errfunc;
   L->errfunc = ef;
   status = luaD_rawrunprotected(L, func, u);
-  if (status != 0) {  /* an error occurred? */
+  if (status != LUA_OK) {  /* an error occurred? */
     StkId oldtop = restorestack(L, old_top);
-    luaF_close(L, oldtop);  /* close eventual pending closures */
-    luaD_seterrorobj(L, status, oldtop);
-    L->nCcalls = oldnCcalls;
-    L->ci = restoreci(L, old_ci);
-    L->base = L->ci->base;
-    L->savedpc = L->ci->savedpc;
+    luaF_close(L, oldtop);  /* close possible pending closures */
+    seterrorobj(L, status, oldtop);
+    L->ci = old_ci;
     L->allowhook = old_allowhooks;
-    restore_stack_limit(L);
+    L->nny = old_nny;
+    luaD_shrinkstack(L);
   }
   L->errfunc = old_errfunc;
   return status;
@@ -483,7 +609,8 @@ int luaD_pcall (lua_State *L, Pfunc func, void *u,
 */
 struct SParser {  /* data to `f_parser' */
   ZIO *z;
-  Mbuffer buff;  /* buffer to be used by the scanner */
+  Mbuffer buff;  /* dynamic structure used by the scanner */
+  Dyndata dyd;  /* dynamic structures used by the parser */
   const char *name;
 };
 
@@ -492,26 +619,34 @@ static void f_parser (lua_State *L, void *ud) {
   Proto *tf;
   Closure *cl;
   struct SParser *p = cast(struct SParser *, ud);
-  int c = luaZ_lookahead(p->z);
-  luaC_checkGC(L);
-  tf = ((c == LUA_SIGNATURE[0]) ? luaU_undump : luaY_parser)(L, p->z,
-                                                             &p->buff, p->name);
-  cl = luaF_newLclosure(L, tf->nups, hvalue(gt(L)));
-  cl->l.p = tf;
-  for (i = 0; i < tf->nups; i++)  /* initialize eventual upvalues */
-    cl->l.upvals[i] = luaF_newupval(L);
-  setclvalue(L, L->top, cl);
+  int c = zgetc(p->z);  /* read first character */
+  tf = (c == LUA_SIGNATURE[0])
+           ? luaU_undump(L, p->z, &p->buff, p->name)
+           : luaY_parser(L, p->z, &p->buff, &p->dyd, p->name, c);
+  setptvalue2s(L, L->top, tf);
   incr_top(L);
+  cl = luaF_newLclosure(L, tf);
+  setclLvalue(L, L->top - 1, cl);
+  for (i = 0; i < tf->sizeupvalues; i++)  /* initialize upvalues */
+    cl->l.upvals[i] = luaF_newupval(L);
 }
 
 
 int luaD_protectedparser (lua_State *L, ZIO *z, const char *name) {
   struct SParser p;
   int status;
+  L->nny++;  /* cannot yield during parsing */
   p.z = z; p.name = name;
+  p.dyd.actvar.arr = NULL; p.dyd.actvar.size = 0;
+  p.dyd.gt.arr = NULL; p.dyd.gt.size = 0;
+  p.dyd.label.arr = NULL; p.dyd.label.size = 0;
   luaZ_initbuffer(L, &p.buff);
   status = luaD_pcall(L, f_parser, &p, savestack(L, L->top), L->errfunc);
   luaZ_freebuffer(L, &p.buff);
+  luaM_freearray(L, p.dyd.actvar.arr, p.dyd.actvar.size);
+  luaM_freearray(L, p.dyd.gt.arr, p.dyd.gt.size);
+  luaM_freearray(L, p.dyd.label.arr, p.dyd.label.size);
+  L->nny--;
   return status;
 }
 
diff --git a/src/ldo.h b/src/ldo.h
index 98fddac..88962d9 100644..100755
--- a/src/ldo.h
+++ b/src/ldo.h
@@ -1,5 +1,5 @@
 /*
-** $Id: ldo.h,v 2.7.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: ldo.h,v 2.18 2009/12/17 12:28:57 roberto Exp $
 ** Stack and Call structure of Lua
 ** See Copyright Notice in lua.h
 */
@@ -13,45 +13,33 @@
 #include "lzio.h"
 
 
-#define luaD_checkstack(L,n)	\
-  if ((char *)L->stack_last - (char *)L->top <= (n)*(int)sizeof(TValue)) \
-    luaD_growstack(L, n); \
-  else condhardstacktests(luaD_reallocstack(L, L->stacksize - EXTRA_STACK - 1));
+#define luaD_checkstack(L,n)	if (L->stack_last - L->top <= (n)) \
+				    luaD_growstack(L, n); else condmovestack(L);
 
 
-#define incr_top(L) {luaD_checkstack(L,1); L->top++;}
+#define incr_top(L) {L->top++; luaD_checkstack(L,0);}
 
 #define savestack(L,p)		((char *)(p) - (char *)L->stack)
 #define restorestack(L,n)	((TValue *)((char *)L->stack + (n)))
 
-#define saveci(L,p)		((char *)(p) - (char *)L->base_ci)
-#define restoreci(L,n)		((CallInfo *)((char *)L->base_ci + (n)))
-
-
-/* results from luaD_precall */
-#define PCRLUA		0	/* initiated a call to a Lua function */
-#define PCRC		1	/* did a call to a C function */
-#define PCRYIELD	2	/* C funtion yielded */
-
 
 /* type of protected functions, to be ran by `runprotected' */
 typedef void (*Pfunc) (lua_State *L, void *ud);
 
 LUAI_FUNC int luaD_protectedparser (lua_State *L, ZIO *z, const char *name);
-LUAI_FUNC void luaD_callhook (lua_State *L, int event, int line);
+LUAI_FUNC void luaD_hook (lua_State *L, int event, int line);
 LUAI_FUNC int luaD_precall (lua_State *L, StkId func, int nresults);
-LUAI_FUNC void luaD_call (lua_State *L, StkId func, int nResults);
+LUAI_FUNC void luaD_call (lua_State *L, StkId func, int nResults,
+                                        int allowyield);
 LUAI_FUNC int luaD_pcall (lua_State *L, Pfunc func, void *u,
                                         ptrdiff_t oldtop, ptrdiff_t ef);
 LUAI_FUNC int luaD_poscall (lua_State *L, StkId firstResult);
-LUAI_FUNC void luaD_reallocCI (lua_State *L, int newsize);
 LUAI_FUNC void luaD_reallocstack (lua_State *L, int newsize);
 LUAI_FUNC void luaD_growstack (lua_State *L, int n);
+LUAI_FUNC void luaD_shrinkstack (lua_State *L);
 
 LUAI_FUNC void luaD_throw (lua_State *L, int errcode);
 LUAI_FUNC int luaD_rawrunprotected (lua_State *L, Pfunc f, void *ud);
 
-LUAI_FUNC void luaD_seterrorobj (lua_State *L, int errcode, StkId oldtop);
-
 #endif
 
diff --git a/src/ldump.c b/src/ldump.c
index c9d3d48..77b578d 100644..100755
--- a/src/ldump.c
+++ b/src/ldump.c
@@ -1,5 +1,5 @@
 /*
-** $Id: ldump.c,v 2.8.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: ldump.c,v 1.18 2011/05/06 13:35:17 lhf Exp $
 ** save precompiled Lua chunks
 ** See Copyright Notice in lua.h
 */
@@ -24,7 +24,7 @@ typedef struct {
 } DumpState;
 
 #define DumpMem(b,n,size,D)	DumpBlock(b,(n)*(size),D)
-#define DumpVar(x,D)	 	DumpMem(&x,1,sizeof(x),D)
+#define DumpVar(x,D)		DumpMem(&x,1,sizeof(x),D)
 
 static void DumpBlock(const void* b, size_t size, DumpState* D)
 {
@@ -60,7 +60,7 @@ static void DumpVector(const void* b, int n, size_t size, DumpState* D)
 
 static void DumpString(const TString* s, DumpState* D)
 {
- if (s==NULL || getstr(s)==NULL)
+ if (s==NULL)
  {
   size_t size=0;
   DumpVar(size,D);
@@ -69,13 +69,13 @@ static void DumpString(const TString* s, DumpState* D)
  {
   size_t size=s->tsv.len+1;		/* include trailing '\0' */
   DumpVar(size,D);
-  DumpBlock(getstr(s),size,D);
+  DumpBlock(getstr(s),size*sizeof(char),D);
  }
 }
 
 #define DumpCode(f,D)	 DumpVector(f->code,f->sizecode,sizeof(Instruction),D)
 
-static void DumpFunction(const Proto* f, const TString* p, DumpState* D);
+static void DumpFunction(const Proto* f, DumpState* D);
 
 static void DumpConstants(const Proto* f, DumpState* D)
 {
@@ -98,19 +98,28 @@ static void DumpConstants(const Proto* f, DumpState* D)
    case LUA_TSTRING:
 	DumpString(rawtsvalue(o),D);
 	break;
-   default:
-	lua_assert(0);			/* cannot happen */
-	break;
   }
  }
  n=f->sizep;
  DumpInt(n,D);
- for (i=0; i<n; i++) DumpFunction(f->p[i],f->source,D);
+ for (i=0; i<n; i++) DumpFunction(f->p[i],D);
+}
+
+static void DumpUpvalues(const Proto* f, DumpState* D)
+{
+ int i,n=f->sizeupvalues;
+ DumpInt(n,D);
+ for (i=0; i<n; i++)
+ {
+  DumpChar(f->upvalues[i].instack, D);
+  DumpChar(f->upvalues[i].idx, D);
+ }
 }
 
 static void DumpDebug(const Proto* f, DumpState* D)
 {
  int i,n;
+ DumpString((D->strip) ? NULL : f->source,D);
  n= (D->strip) ? 0 : f->sizelineinfo;
  DumpVector(f->lineinfo,n,sizeof(int),D);
  n= (D->strip) ? 0 : f->sizelocvars;
@@ -123,26 +132,25 @@ static void DumpDebug(const Proto* f, DumpState* D)
  }
  n= (D->strip) ? 0 : f->sizeupvalues;
  DumpInt(n,D);
- for (i=0; i<n; i++) DumpString(f->upvalues[i],D);
+ for (i=0; i<n; i++) DumpString(f->upvalues[i].name,D);
 }
 
-static void DumpFunction(const Proto* f, const TString* p, DumpState* D)
+static void DumpFunction(const Proto* f, DumpState* D)
 {
- DumpString((f->source==p || D->strip) ? NULL : f->source,D);
  DumpInt(f->linedefined,D);
  DumpInt(f->lastlinedefined,D);
- DumpChar(f->nups,D);
  DumpChar(f->numparams,D);
  DumpChar(f->is_vararg,D);
  DumpChar(f->maxstacksize,D);
  DumpCode(f,D);
  DumpConstants(f,D);
+ DumpUpvalues(f,D);
  DumpDebug(f,D);
 }
 
 static void DumpHeader(DumpState* D)
 {
- char h[LUAC_HEADERSIZE];
+ lu_byte h[LUAC_HEADERSIZE];
  luaU_header(h);
  DumpBlock(h,LUAC_HEADERSIZE,D);
 }
@@ -159,6 +167,6 @@ int luaU_dump (lua_State* L, const Proto* f, lua_Writer w, void* data, int strip
  D.strip=strip;
  D.status=0;
  DumpHeader(&D);
- DumpFunction(f,NULL,&D);
+ DumpFunction(f,&D);
  return D.status;
 }
diff --git a/src/lfunc.c b/src/lfunc.c
index 813e88f..1a1a8bb 100644..100755
--- a/src/lfunc.c
+++ b/src/lfunc.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lfunc.c,v 2.12.1.2 2007/12/28 14:58:43 roberto Exp $
+** $Id: lfunc.c,v 2.27 2010/06/30 14:11:17 roberto Exp $
 ** Auxiliary functions to manipulate prototypes and closures
 ** See Copyright Notice in lua.h
 */
@@ -20,30 +20,27 @@
 
 
 
-Closure *luaF_newCclosure (lua_State *L, int nelems, Table *e) {
-  Closure *c = cast(Closure *, luaM_malloc(L, sizeCclosure(nelems)));
-  luaC_link(L, obj2gco(c), LUA_TFUNCTION);
+Closure *luaF_newCclosure (lua_State *L, int n) {
+  Closure *c = &luaC_newobj(L, LUA_TFUNCTION, sizeCclosure(n), NULL, 0)->cl;
   c->c.isC = 1;
-  c->c.env = e;
-  c->c.nupvalues = cast_byte(nelems);
+  c->c.nupvalues = cast_byte(n);
   return c;
 }
 
 
-Closure *luaF_newLclosure (lua_State *L, int nelems, Table *e) {
-  Closure *c = cast(Closure *, luaM_malloc(L, sizeLclosure(nelems)));
-  luaC_link(L, obj2gco(c), LUA_TFUNCTION);
+Closure *luaF_newLclosure (lua_State *L, Proto *p) {
+  int n = p->sizeupvalues;
+  Closure *c = &luaC_newobj(L, LUA_TFUNCTION, sizeLclosure(n), NULL, 0)->cl;
   c->l.isC = 0;
-  c->l.env = e;
-  c->l.nupvalues = cast_byte(nelems);
-  while (nelems--) c->l.upvals[nelems] = NULL;
+  c->l.p = p;
+  c->l.nupvalues = cast_byte(n);
+  while (n--) c->l.upvals[n] = NULL;
   return c;
 }
 
 
 UpVal *luaF_newupval (lua_State *L) {
-  UpVal *uv = luaM_new(L, UpVal);
-  luaC_link(L, obj2gco(uv), LUA_TUPVAL);
+  UpVal *uv = &luaC_newobj(L, LUA_TUPVAL, sizeof(UpVal), NULL, 0)->uv;
   uv->v = &uv->u.value;
   setnilvalue(uv->v);
   return uv;
@@ -55,21 +52,20 @@ UpVal *luaF_findupval (lua_State *L, StkId level) {
   GCObject **pp = &L->openupval;
   UpVal *p;
   UpVal *uv;
-  while (*pp != NULL && (p = ngcotouv(*pp))->v >= level) {
+  while (*pp != NULL && (p = gco2uv(*pp))->v >= level) {
+    GCObject *o = obj2gco(p);
     lua_assert(p->v != &p->u.value);
     if (p->v == level) {  /* found a corresponding upvalue? */
-      if (isdead(g, obj2gco(p)))  /* is it dead? */
-        changewhite(obj2gco(p));  /* ressurect it */
+      if (isdead(g, o))  /* is it dead? */
+        changewhite(o);  /* resurrect it */
       return p;
     }
+    resetoldbit(o);  /* may create a newer upval after this one */
     pp = &p->next;
   }
-  uv = luaM_new(L, UpVal);  /* not found: create a new one */
-  uv->tt = LUA_TUPVAL;
-  uv->marked = luaC_white(g);
+  /* not found: create a new one */
+  uv = &luaC_newobj(L, LUA_TUPVAL, sizeof(UpVal), pp, 0)->uv;
   uv->v = level;  /* current value lives in the stack */
-  uv->next = *pp;  /* chain it in the proper position */
-  *pp = obj2gco(uv);
   uv->u.l.prev = &g->uvhead;  /* double link it in `uvhead' list */
   uv->u.l.next = g->uvhead.u.l.next;
   uv->u.l.next->u.l.prev = uv;
@@ -96,41 +92,42 @@ void luaF_freeupval (lua_State *L, UpVal *uv) {
 void luaF_close (lua_State *L, StkId level) {
   UpVal *uv;
   global_State *g = G(L);
-  while (L->openupval != NULL && (uv = ngcotouv(L->openupval))->v >= level) {
+  while (L->openupval != NULL && (uv = gco2uv(L->openupval))->v >= level) {
     GCObject *o = obj2gco(uv);
     lua_assert(!isblack(o) && uv->v != &uv->u.value);
     L->openupval = uv->next;  /* remove from `open' list */
     if (isdead(g, o))
       luaF_freeupval(L, uv);  /* free upvalue */
     else {
-      unlinkupval(uv);
-      setobj(L, &uv->u.value, uv->v);
+      unlinkupval(uv);  /* remove upvalue from 'uvhead' list */
+      setobj(L, &uv->u.value, uv->v);  /* move value to upvalue slot */
       uv->v = &uv->u.value;  /* now current value lives here */
-      luaC_linkupval(L, uv);  /* link upvalue into `gcroot' list */
+      gch(o)->next = g->allgc;  /* link upvalue into 'allgc' list */
+      g->allgc = o;
+      luaC_checkupvalcolor(g, uv);
     }
   }
 }
 
 
 Proto *luaF_newproto (lua_State *L) {
-  Proto *f = luaM_new(L, Proto);
-  luaC_link(L, obj2gco(f), LUA_TPROTO);
+  Proto *f = &luaC_newobj(L, LUA_TPROTO, sizeof(Proto), NULL, 0)->p;
   f->k = NULL;
   f->sizek = 0;
   f->p = NULL;
   f->sizep = 0;
   f->code = NULL;
+  f->cache = NULL;
   f->sizecode = 0;
+  f->lineinfo = NULL;
   f->sizelineinfo = 0;
-  f->sizeupvalues = 0;
-  f->nups = 0;
   f->upvalues = NULL;
+  f->sizeupvalues = 0;
   f->numparams = 0;
   f->is_vararg = 0;
   f->maxstacksize = 0;
-  f->lineinfo = NULL;
-  f->sizelocvars = 0;
   f->locvars = NULL;
+  f->sizelocvars = 0;
   f->linedefined = 0;
   f->lastlinedefined = 0;
   f->source = NULL;
@@ -139,12 +136,12 @@ Proto *luaF_newproto (lua_State *L) {
 
 
 void luaF_freeproto (lua_State *L, Proto *f) {
-  luaM_freearray(L, f->code, f->sizecode, Instruction);
-  luaM_freearray(L, f->p, f->sizep, Proto *);
-  luaM_freearray(L, f->k, f->sizek, TValue);
-  luaM_freearray(L, f->lineinfo, f->sizelineinfo, int);
-  luaM_freearray(L, f->locvars, f->sizelocvars, struct LocVar);
-  luaM_freearray(L, f->upvalues, f->sizeupvalues, TString *);
+  luaM_freearray(L, f->code, f->sizecode);
+  luaM_freearray(L, f->p, f->sizep);
+  luaM_freearray(L, f->k, f->sizek);
+  luaM_freearray(L, f->lineinfo, f->sizelineinfo);
+  luaM_freearray(L, f->locvars, f->sizelocvars);
+  luaM_freearray(L, f->upvalues, f->sizeupvalues);
   luaM_free(L, f);
 }
 
diff --git a/src/lfunc.h b/src/lfunc.h
index a68cf51..da18923 100644..100755
--- a/src/lfunc.h
+++ b/src/lfunc.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lfunc.h,v 2.4.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lfunc.h,v 2.6 2010/06/04 13:06:15 roberto Exp $
 ** Auxiliary functions to manipulate prototypes and closures
 ** See Copyright Notice in lua.h
 */
@@ -19,8 +19,8 @@
 
 
 LUAI_FUNC Proto *luaF_newproto (lua_State *L);
-LUAI_FUNC Closure *luaF_newCclosure (lua_State *L, int nelems, Table *e);
-LUAI_FUNC Closure *luaF_newLclosure (lua_State *L, int nelems, Table *e);
+LUAI_FUNC Closure *luaF_newCclosure (lua_State *L, int nelems);
+LUAI_FUNC Closure *luaF_newLclosure (lua_State *L, Proto *p);
 LUAI_FUNC UpVal *luaF_newupval (lua_State *L);
 LUAI_FUNC UpVal *luaF_findupval (lua_State *L, StkId level);
 LUAI_FUNC void luaF_close (lua_State *L, StkId level);
diff --git a/src/lgc.c b/src/lgc.c
index d9e0b78..598cc71 100644..100755
--- a/src/lgc.c
+++ b/src/lgc.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lgc.c,v 2.38.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lgc.c,v 2.109 2011/05/05 19:42:25 roberto Exp $
 ** Garbage Collector
 ** See Copyright Notice in lua.h
 */
@@ -23,68 +23,240 @@
 #include "ltm.h"
 
 
-#define GCSTEPSIZE	1024u
+
+/* how much to allocate before next GC step */
+#define GCSTEPSIZE	1024
+
+/* maximum number of elements to sweep in each single step */
 #define GCSWEEPMAX	40
-#define GCSWEEPCOST	10
-#define GCFINALIZECOST	100
 
+/* cost of sweeping one element */
+#define GCSWEEPCOST	1
+
+/* maximum number of finalizers to call in each GC step */
+#define GCFINALIZENUM	4
+
+/* cost of marking the root set */
+#define GCROOTCOST	10
+
+/* cost of atomic step */
+#define GCATOMICCOST	1000
+
+/* basic cost to traverse one object (to be added to the links the
+   object may have) */
+#define TRAVCOST	5
+
+
+/*
+** standard negative debt for GC; a reasonable "time" to wait before
+** starting a new cycle
+*/
+#define stddebt(g)	(-cast(l_mem, gettotalbytes(g)/100) * g->gcpause)
 
-#define maskmarks	cast_byte(~(bitmask(BLACKBIT)|WHITEBITS))
 
+/*
+** 'makewhite' erases all color bits plus the old bit and then
+** sets only the current white bit
+*/
+#define maskcolors	(~(bit2mask(BLACKBIT, OLDBIT) | WHITEBITS))
 #define makewhite(g,x)	\
-   ((x)->gch.marked = cast_byte(((x)->gch.marked & maskmarks) | luaC_white(g)))
+ (gch(x)->marked = cast_byte((gch(x)->marked & maskcolors) | luaC_white(g)))
 
-#define white2gray(x)	reset2bits((x)->gch.marked, WHITE0BIT, WHITE1BIT)
-#define black2gray(x)	resetbit((x)->gch.marked, BLACKBIT)
+#define white2gray(x)	resetbits(gch(x)->marked, WHITEBITS)
+#define black2gray(x)	resetbit(gch(x)->marked, BLACKBIT)
 
-#define stringmark(s)	reset2bits((s)->tsv.marked, WHITE0BIT, WHITE1BIT)
+#define stringmark(s)	((void)((s) && resetbits((s)->tsv.marked, WHITEBITS)))
 
 
-#define isfinalized(u)		testbit((u)->marked, FINALIZEDBIT)
-#define markfinalized(u)	l_setbit((u)->marked, FINALIZEDBIT)
+#define isfinalized(x)		testbit(gch(x)->marked, FINALIZEDBIT)
 
+#define checkdeadkey(n)	lua_assert(!ttisdeadkey(gkey(n)) || ttisnil(gval(n)))
 
-#define KEYWEAK         bitmask(KEYWEAKBIT)
-#define VALUEWEAK       bitmask(VALUEWEAKBIT)
 
+#define checkconsistency(obj)  \
+  lua_longassert(!iscollectable(obj) || righttt(obj))
 
 
 #define markvalue(g,o) { checkconsistency(o); \
-  if (iscollectable(o) && iswhite(gcvalue(o))) reallymarkobject(g,gcvalue(o)); }
+  if (valiswhite(o)) reallymarkobject(g,gcvalue(o)); }
 
-#define markobject(g,t) { if (iswhite(obj2gco(t))) \
+#define markobject(g,t) { if ((t) && iswhite(obj2gco(t))) \
 		reallymarkobject(g, obj2gco(t)); }
 
+static void reallymarkobject (global_State *g, GCObject *o);
+
+
+/*
+** {======================================================
+** Generic functions
+** =======================================================
+*/
+
 
-#define setthreshold(g)  (g->GCthreshold = (g->estimate/100) * g->gcpause)
+/*
+** link table 'h' into list pointed by 'p'
+*/
+#define linktable(h,p)	((h)->gclist = *(p), *(p) = obj2gco(h))
 
 
+/*
+** mark a table entry as dead (therefore removing it from the table)
+*/
 static void removeentry (Node *n) {
   lua_assert(ttisnil(gval(n)));
   if (iscollectable(gkey(n)))
-    setttype(gkey(n), LUA_TDEADKEY);  /* dead key; remove it */
+    setdeadvalue(gkey(n));  /* dead key; remove it */
+}
+
+
+/*
+** tells whether a key or value can be cleared from a weak
+** table. Non-collectable objects are never removed from weak
+** tables. Strings behave as `values', so are never removed too. for
+** other objects: if really collected, cannot keep them; for objects
+** being finalized, keep them in keys, but not in values
+*/
+static int iscleared (const TValue *o, int iskey) {
+  if (!iscollectable(o)) return 0;
+  else if (ttisstring(o)) {
+    stringmark(rawtsvalue(o));  /* strings are `values', so are never weak */
+    return 0;
+  }
+  else return iswhite(gcvalue(o)) || (!iskey && isfinalized(gcvalue(o)));
+}
+
+
+/*
+** barrier that moves collector forward, that is, mark the white object
+** being pointed by a black object.
+*/
+void luaC_barrier_ (lua_State *L, GCObject *o, GCObject *v) {
+  global_State *g = G(L);
+  lua_assert(isblack(o) && iswhite(v) && !isdead(g, v) && !isdead(g, o));
+  lua_assert(isgenerational(g) || g->gcstate != GCSpause);
+  lua_assert(gch(o)->tt != LUA_TTABLE);
+  if (keepinvariant(g))  /* must keep invariant? */
+    reallymarkobject(g, v);  /* restore invariant */
+  else {  /* sweep phase */
+    lua_assert(issweepphase(g));
+    makewhite(g, o);  /* mark main obj. as white to avoid other barriers */
+  }
+}
+
+
+/*
+** barrier that moves collector backward, that is, mark the black object
+** pointing to a white object as gray again. (Current implementation
+** only works for tables; access to 'gclist' is not uniform across
+** different types.)
+*/
+void luaC_barrierback_ (lua_State *L, GCObject *o) {
+  global_State *g = G(L);
+  lua_assert(isblack(o) && !isdead(g, o));
+  black2gray(o);  /* make object gray (again) */
+  gco2t(o)->gclist = g->grayagain;
+  g->grayagain = o;
+}
+
+
+/*
+** barrier for prototypes. When creating first closure (cache is
+** NULL), use a forward barrier; this may be the only closure of the
+** prototype (if it is a "regular" function, with a single instance)
+** and the prototype may be big, so it is better to avoid traversing
+** it again. Otherwise, use a backward barrier, to avoid marking all
+** possible instances.
+*/
+LUAI_FUNC void luaC_barrierproto_ (lua_State *L, Proto *p, Closure *c) {
+  global_State *g = G(L);
+  lua_assert(isblack(obj2gco(p)));
+  if (p->cache == NULL) {  /* first time? */
+    luaC_objbarrier(L, p, c);
+  }
+  else {  /* use a backward barrier */
+    black2gray(obj2gco(p));  /* make prototype gray (again) */
+    p->gclist = g->grayagain;
+    g->grayagain = obj2gco(p);
+  }
 }
 
 
+/*
+** check color (and invariants) for an upvalue that was closed,
+** i.e., moved into the 'allgc' list
+*/
+void luaC_checkupvalcolor (global_State *g, UpVal *uv) {
+  GCObject *o = obj2gco(uv);
+  lua_assert(!isblack(o));  /* open upvalues are never black */
+  if (isgray(o)) {
+    if (keepinvariant(g)) {
+      resetoldbit(o);  /* see MOVE OLD rule */
+      gray2black(o);  /* it is being visited now */
+      markvalue(g, uv->v);
+    }
+    else {
+      lua_assert(issweepphase(g));
+      makewhite(g, o);
+    }
+  }
+}
+
+
+/*
+** create a new collectable object (with given type and size) and link
+** it to '*list'. 'offset' tells how many bytes to allocate before the
+** object itself (used only by states).
+*/
+GCObject *luaC_newobj (lua_State *L, int tt, size_t sz, GCObject **list,
+                       int offset) {
+  global_State *g = G(L);
+  GCObject *o = obj2gco(cast(char *, luaM_newobject(L, tt, sz)) + offset);
+  if (list == NULL)
+    list = &g->allgc;  /* standard list for collectable objects */
+  gch(o)->marked = luaC_white(g);
+  gch(o)->tt = tt;
+  gch(o)->next = *list;
+  *list = o;
+  return o;
+}
+
+/* }====================================================== */
+
+
+
+/*
+** {======================================================
+** Mark functions
+** =======================================================
+*/
+
+
+/*
+** mark an object. Userdata and closed upvalues are visited and turned
+** black here. Strings remain gray (it is the same as making them
+** black). Other objects are marked gray and added to appropriate list
+** to be visited (and turned black) later. (Open upvalues are already
+** linked in 'headuv' list.)
+*/
 static void reallymarkobject (global_State *g, GCObject *o) {
   lua_assert(iswhite(o) && !isdead(g, o));
   white2gray(o);
-  switch (o->gch.tt) {
+  switch (gch(o)->tt) {
     case LUA_TSTRING: {
-      return;
+      return;  /* for strings, gray is as good as black */
     }
     case LUA_TUSERDATA: {
       Table *mt = gco2u(o)->metatable;
-      gray2black(o);  /* udata are never gray */
-      if (mt) markobject(g, mt);
+      markobject(g, mt);
       markobject(g, gco2u(o)->env);
+      gray2black(o);  /* all pointers marked */
       return;
     }
     case LUA_TUPVAL: {
       UpVal *uv = gco2uv(o);
       markvalue(g, uv->v);
-      if (uv->v == &uv->u.value)  /* closed? */
-        gray2black(o);  /* open upvalues are never black */
+      if (uv->v == &uv->u.value)  /* closed? (open upvalues remain gray) */
+        gray2black(o);  /* make it black */
       return;
     }
     case LUA_TFUNCTION: {
@@ -93,8 +265,7 @@ static void reallymarkobject (global_State *g, GCObject *o) {
       break;
     }
     case LUA_TTABLE: {
-      gco2h(o)->gclist = g->gray;
-      g->gray = o;
+      linktable(gco2t(o), &g->gray);
       break;
     }
     case LUA_TTHREAD: {
@@ -112,117 +283,175 @@ static void reallymarkobject (global_State *g, GCObject *o) {
 }
 
 
-static void marktmu (global_State *g) {
-  GCObject *u = g->tmudata;
-  if (u) {
-    do {
-      u = u->gch.next;
-      makewhite(g, u);  /* may be marked, if left from previous GC */
-      reallymarkobject(g, u);
-    } while (u != g->tmudata);
+/*
+** mark tag methods for basic types
+*/
+static void markmt (global_State *g) {
+  int i;
+  for (i=0; i < LUA_NUMTAGS; i++)
+    markobject(g, g->mt[i]);
+}
+
+
+/*
+** mark all objects in list of being-finalized
+*/
+static void markbeingfnz (global_State *g) {
+  GCObject *o;
+  for (o = g->tobefnz; o != NULL; o = gch(o)->next) {
+    makewhite(g, o);
+    reallymarkobject(g, o);
   }
 }
 
 
-/* move `dead' udata that need finalization to list `tmudata' */
-size_t luaC_separateudata (lua_State *L, int all) {
-  global_State *g = G(L);
-  size_t deadmem = 0;
-  GCObject **p = &g->mainthread->next;
-  GCObject *curr;
-  while ((curr = *p) != NULL) {
-    if (!(iswhite(curr) || all) || isfinalized(gco2u(curr)))
-      p = &curr->gch.next;  /* don't bother with them */
-    else if (fasttm(L, gco2u(curr)->metatable, TM_GC) == NULL) {
-      markfinalized(gco2u(curr));  /* don't need finalization */
-      p = &curr->gch.next;
-    }
-    else {  /* must call its gc method */
-      deadmem += sizeudata(gco2u(curr));
-      markfinalized(gco2u(curr));
-      *p = curr->gch.next;
-      /* link `curr' at the end of `tmudata' list */
-      if (g->tmudata == NULL)  /* list is empty? */
-        g->tmudata = curr->gch.next = curr;  /* creates a circular list */
-      else {
-        curr->gch.next = g->tmudata->gch.next;
-        g->tmudata->gch.next = curr;
-        g->tmudata = curr;
-      }
+/*
+** mark all values stored in marked open upvalues. (See comment in
+** 'lstate.h'.)
+*/
+static void remarkupvals (global_State *g) {
+  UpVal *uv;
+  for (uv = g->uvhead.u.l.next; uv != &g->uvhead; uv = uv->u.l.next) {
+    if (isgray(obj2gco(uv)))
+      markvalue(g, uv->v);
+  }
+}
+
+
+/*
+** mark root set and reset all gray lists, to start a new
+** incremental (or full) collection
+*/
+static void markroot (global_State *g) {
+  g->gray = g->grayagain = NULL;
+  g->weak = g->allweak = g->ephemeron = NULL;
+  markobject(g, g->mainthread);
+  markvalue(g, &g->l_registry);
+  markmt(g);
+  markbeingfnz(g);  /* mark any finalizing object left from previous cycle */
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Traverse functions
+** =======================================================
+*/
+
+static void traverseweakvalue (global_State *g, Table *h) {
+  Node *n, *limit = gnode(h, sizenode(h));
+  for (n = gnode(h, 0); n < limit; n++) {
+    checkdeadkey(n);
+    if (ttisnil(gval(n)))  /* entry is empty? */
+      removeentry(n);  /* remove it */
+    else {
+      lua_assert(!ttisnil(gkey(n)));
+      markvalue(g, gkey(n));  /* mark key */
     }
   }
-  return deadmem;
+  linktable(h, &g->weak);  /* link into appropriate list */
 }
 
 
-static int traversetable (global_State *g, Table *h) {
+static int traverseephemeron (global_State *g, Table *h) {
+  int marked = 0;  /* true if an object is marked in this traversal */
+  int hasclears = 0;  /* true if table has unmarked pairs */
+  Node *n, *limit = gnode(h, sizenode(h));
   int i;
-  int weakkey = 0;
-  int weakvalue = 0;
-  const TValue *mode;
-  if (h->metatable)
-    markobject(g, h->metatable);
-  mode = gfasttm(g, h->metatable, TM_MODE);
-  if (mode && ttisstring(mode)) {  /* is there a weak mode? */
-    weakkey = (strchr(svalue(mode), 'k') != NULL);
-    weakvalue = (strchr(svalue(mode), 'v') != NULL);
-    if (weakkey || weakvalue) {  /* is really weak? */
-      h->marked &= ~(KEYWEAK | VALUEWEAK);  /* clear bits */
-      h->marked |= cast_byte((weakkey << KEYWEAKBIT) |
-                             (weakvalue << VALUEWEAKBIT));
-      h->gclist = g->weak;  /* must be cleared after GC, ... */
-      g->weak = obj2gco(h);  /* ... so put in the appropriate list */
+  /* traverse array part (numeric keys are 'strong') */
+  for (i = 0; i < h->sizearray; i++) {
+    if (valiswhite(&h->array[i])) {
+      marked = 1;
+      reallymarkobject(g, gcvalue(&h->array[i]));
     }
   }
-  if (weakkey && weakvalue) return 1;
-  if (!weakvalue) {
-    i = h->sizearray;
-    while (i--)
-      markvalue(g, &h->array[i]);
-  }
-  i = sizenode(h);
-  while (i--) {
-    Node *n = gnode(h, i);
-    lua_assert(ttype(gkey(n)) != LUA_TDEADKEY || ttisnil(gval(n)));
-    if (ttisnil(gval(n)))
-      removeentry(n);  /* remove empty entries */
-    else {
-      lua_assert(!ttisnil(gkey(n)));
-      if (!weakkey) markvalue(g, gkey(n));
-      if (!weakvalue) markvalue(g, gval(n));
+  /* traverse hash part */
+  for (n = gnode(h, 0); n < limit; n++) {
+    checkdeadkey(n);
+    if (ttisnil(gval(n)))  /* entry is empty? */
+      removeentry(n);  /* remove it */
+    else if (valiswhite(gval(n))) {  /* value not marked yet? */
+      if (iscleared(gkey(n), 1))  /* key is not marked (yet)? */
+        hasclears = 1;  /* may have to propagate mark from key to value */
+      else {  /* key is marked, so mark value */
+        marked = 1;  /* value was not marked */
+        reallymarkobject(g, gcvalue(gval(n)));
+      }
     }
   }
-  return weakkey || weakvalue;
+  if (hasclears)  /* does table have unmarked pairs? */
+    linktable(h, &g->ephemeron);  /* will have to propagate again */
+  else  /* nothing to propagate */
+    linktable(h, &g->weak);  /* avoid convergence phase  */
+  return marked;
 }
 
 
-/*
-** All marks are conditional because a GC may happen while the
-** prototype is still being created
-*/
-static void traverseproto (global_State *g, Proto *f) {
+static void traversestrongtable (global_State *g, Table *h) {
+  Node *n, *limit = gnode(h, sizenode(h));
   int i;
-  if (f->source) stringmark(f->source);
-  for (i=0; i<f->sizek; i++)  /* mark literals */
-    markvalue(g, &f->k[i]);
-  for (i=0; i<f->sizeupvalues; i++) {  /* mark upvalue names */
-    if (f->upvalues[i])
-      stringmark(f->upvalues[i]);
-  }
-  for (i=0; i<f->sizep; i++) {  /* mark nested protos */
-    if (f->p[i])
-      markobject(g, f->p[i]);
+  for (i = 0; i < h->sizearray; i++)  /* traverse array part */
+    markvalue(g, &h->array[i]);
+  for (n = gnode(h, 0); n < limit; n++) {  /* traverse hash part */
+    checkdeadkey(n);
+    if (ttisnil(gval(n)))  /* entry is empty? */
+      removeentry(n);  /* remove it */
+    else {
+      lua_assert(!ttisnil(gkey(n)));
+      markvalue(g, gkey(n));  /* mark key */
+      markvalue(g, gval(n));  /* mark value */
+    }
   }
-  for (i=0; i<f->sizelocvars; i++) {  /* mark local-variable names */
-    if (f->locvars[i].varname)
-      stringmark(f->locvars[i].varname);
+}
+
+
+static int traversetable (global_State *g, Table *h) {
+  const TValue *mode = gfasttm(g, h->metatable, TM_MODE);
+  markobject(g, h->metatable);
+  if (mode && ttisstring(mode)) {  /* is there a weak mode? */
+    int weakkey = (strchr(svalue(mode), 'k') != NULL);
+    int weakvalue = (strchr(svalue(mode), 'v') != NULL);
+    if (weakkey || weakvalue) {  /* is really weak? */
+      black2gray(obj2gco(h));  /* keep table gray */
+      if (!weakkey) {  /* strong keys? */
+        traverseweakvalue(g, h);
+        return TRAVCOST + sizenode(h);
+      }
+      else if (!weakvalue) {  /* strong values? */
+        traverseephemeron(g, h);
+        return TRAVCOST + h->sizearray + sizenode(h);
+      }
+      else {
+        linktable(h, &g->allweak);  /* nothing to traverse now */
+        return TRAVCOST;
+      }
+    }  /* else go through */
   }
+  traversestrongtable(g, h);
+  return TRAVCOST + h->sizearray + (2 * sizenode(h));
 }
 
 
+static int traverseproto (global_State *g, Proto *f) {
+  int i;
+  if (f->cache && iswhite(obj2gco(f->cache)))
+    f->cache = NULL;  /* allow cache to be collected */
+  stringmark(f->source);
+  for (i = 0; i < f->sizek; i++)  /* mark literals */
+    markvalue(g, &f->k[i]);
+  for (i = 0; i < f->sizeupvalues; i++)  /* mark upvalue names */
+    stringmark(f->upvalues[i].name);
+  for (i = 0; i < f->sizep; i++)  /* mark nested protos */
+    markobject(g, f->p[i]);
+  for (i = 0; i < f->sizelocvars; i++)  /* mark local-variable names */
+    stringmark(f->locvars[i].varname);
+  return TRAVCOST + f->sizek + f->sizeupvalues + f->sizep + f->sizelocvars;
+}
 
-static void traverseclosure (global_State *g, Closure *cl) {
-  markobject(g, cl->c.env);
+
+static int traverseclosure (global_State *g, Closure *cl) {
   if (cl->c.isC) {
     int i;
     for (i=0; i<cl->c.nupvalues; i++)  /* mark its upvalues */
@@ -230,69 +459,49 @@ static void traverseclosure (global_State *g, Closure *cl) {
   }
   else {
     int i;
-    lua_assert(cl->l.nupvalues == cl->l.p->nups);
-    markobject(g, cl->l.p);
+    lua_assert(cl->l.nupvalues == cl->l.p->sizeupvalues);
+    markobject(g, cl->l.p);  /* mark its prototype */
     for (i=0; i<cl->l.nupvalues; i++)  /* mark its upvalues */
       markobject(g, cl->l.upvals[i]);
   }
+  return TRAVCOST + cl->c.nupvalues;
 }
 
 
-static void checkstacksizes (lua_State *L, StkId max) {
-  int ci_used = cast_int(L->ci - L->base_ci);  /* number of `ci' in use */
-  int s_used = cast_int(max - L->stack);  /* part of stack in use */
-  if (L->size_ci > LUAI_MAXCALLS)  /* handling overflow? */
-    return;  /* do not touch the stacks */
-  if (4*ci_used < L->size_ci && 2*BASIC_CI_SIZE < L->size_ci)
-    luaD_reallocCI(L, L->size_ci/2);  /* still big enough... */
-  condhardstacktests(luaD_reallocCI(L, ci_used + 1));
-  if (4*s_used < L->stacksize &&
-      2*(BASIC_STACK_SIZE+EXTRA_STACK) < L->stacksize)
-    luaD_reallocstack(L, L->stacksize/2);  /* still big enough... */
-  condhardstacktests(luaD_reallocstack(L, s_used));
-}
-
-
-static void traversestack (global_State *g, lua_State *l) {
-  StkId o, lim;
-  CallInfo *ci;
-  markvalue(g, gt(l));
-  lim = l->top;
-  for (ci = l->base_ci; ci <= l->ci; ci++) {
-    lua_assert(ci->top <= l->stack_last);
-    if (lim < ci->top) lim = ci->top;
-  }
-  for (o = l->stack; o < l->top; o++)
+static int traversestack (global_State *g, lua_State *L) {
+  StkId o = L->stack;
+  if (o == NULL)
+    return 1;  /* stack not completely built yet */
+  for (; o < L->top; o++)
     markvalue(g, o);
-  for (; o <= lim; o++)
-    setnilvalue(o);
-  checkstacksizes(l, lim);
+  if (g->gcstate == GCSatomic) {  /* final traversal? */
+    StkId lim = L->stack + L->stacksize;  /* real end of stack */
+    for (; o < lim; o++)  /* clear not-marked stack slice */
+      setnilvalue(o);
+  }
+  return TRAVCOST + cast_int(o - L->stack);
 }
 
 
 /*
-** traverse one gray object, turning it to black.
-** Returns `quantity' traversed.
+** traverse one gray object, turning it to black (except for threads,
+** which are always gray).
+** Returns number of values traversed.
 */
-static l_mem propagatemark (global_State *g) {
+static int propagatemark (global_State *g) {
   GCObject *o = g->gray;
   lua_assert(isgray(o));
   gray2black(o);
-  switch (o->gch.tt) {
+  switch (gch(o)->tt) {
     case LUA_TTABLE: {
-      Table *h = gco2h(o);
+      Table *h = gco2t(o);
       g->gray = h->gclist;
-      if (traversetable(g, h))  /* table is weak? */
-        black2gray(o);  /* keep it gray */
-      return sizeof(Table) + sizeof(TValue) * h->sizearray +
-                             sizeof(Node) * sizenode(h);
+      return traversetable(g, h);
     }
     case LUA_TFUNCTION: {
       Closure *cl = gco2cl(o);
       g->gray = cl->c.gclist;
-      traverseclosure(g, cl);
-      return (cl->c.isC) ? sizeCclosure(cl->c.nupvalues) :
-                           sizeLclosure(cl->l.nupvalues);
+      return traverseclosure(g, cl);
     }
     case LUA_TTHREAD: {
       lua_State *th = gco2th(o);
@@ -300,306 +509,439 @@ static l_mem propagatemark (global_State *g) {
       th->gclist = g->grayagain;
       g->grayagain = o;
       black2gray(o);
-      traversestack(g, th);
-      return sizeof(lua_State) + sizeof(TValue) * th->stacksize +
-                                 sizeof(CallInfo) * th->size_ci;
+      return traversestack(g, th);
     }
     case LUA_TPROTO: {
       Proto *p = gco2p(o);
       g->gray = p->gclist;
-      traverseproto(g, p);
-      return sizeof(Proto) + sizeof(Instruction) * p->sizecode +
-                             sizeof(Proto *) * p->sizep +
-                             sizeof(TValue) * p->sizek + 
-                             sizeof(int) * p->sizelineinfo +
-                             sizeof(LocVar) * p->sizelocvars +
-                             sizeof(TString *) * p->sizeupvalues;
+      return traverseproto(g, p);
     }
     default: lua_assert(0); return 0;
   }
 }
 
 
-static size_t propagateall (global_State *g) {
-  size_t m = 0;
-  while (g->gray) m += propagatemark(g);
-  return m;
+static void propagateall (global_State *g) {
+  while (g->gray) propagatemark(g);
 }
 
 
+static void traverselistofgrays (global_State *g, GCObject **l) {
+  lua_assert(g->gray == NULL);  /* no grays left */
+  g->gray = *l;  /* now 'l' is new gray list */
+  *l = NULL;
+  propagateall(g);
+}
+
+
+static void convergeephemerons (global_State *g) {
+  int changed;
+  do {
+    GCObject *w;
+    GCObject *next = g->ephemeron;  /* get ephemeron list */
+    g->ephemeron = NULL;  /* tables will return to this list when traversed */
+    changed = 0;
+    while ((w = next) != NULL) {
+      next = gco2t(w)->gclist;
+      if (traverseephemeron(g, gco2t(w))) {  /* traverse marked some value? */
+        propagateall(g);  /* propagate changes */
+        changed = 1;  /* will have to revisit all ephemeron tables */
+      }
+    }
+  } while (changed);
+}
+
+/* }====================================================== */
+
+
 /*
-** The next function tells whether a key or value can be cleared from
-** a weak table. Non-collectable objects are never removed from weak
-** tables. Strings behave as `values', so are never removed too. for
-** other objects: if really collected, cannot keep them; for userdata
-** being finalized, keep them in keys, but not in values
+** {======================================================
+** Sweep Functions
+** =======================================================
 */
-static int iscleared (const TValue *o, int iskey) {
-  if (!iscollectable(o)) return 0;
-  if (ttisstring(o)) {
-    stringmark(rawtsvalue(o));  /* strings are `values', so are never weak */
-    return 0;
-  }
-  return iswhite(gcvalue(o)) ||
-    (ttisuserdata(o) && (!iskey && isfinalized(uvalue(o))));
-}
 
 
 /*
-** clear collected entries from weaktables
+** clear collected entries from all weaktables in list 'l'
 */
 static void cleartable (GCObject *l) {
-  while (l) {
-    Table *h = gco2h(l);
-    int i = h->sizearray;
-    lua_assert(testbit(h->marked, VALUEWEAKBIT) ||
-               testbit(h->marked, KEYWEAKBIT));
-    if (testbit(h->marked, VALUEWEAKBIT)) {
-      while (i--) {
-        TValue *o = &h->array[i];
-        if (iscleared(o, 0))  /* value was collected? */
-          setnilvalue(o);  /* remove value */
-      }
+  for (; l != NULL; l = gco2t(l)->gclist) {
+    Table *h = gco2t(l);
+    Node *n, *limit = gnode(h, sizenode(h));
+    int i;
+    for (i = 0; i < h->sizearray; i++) {
+      TValue *o = &h->array[i];
+      if (iscleared(o, 0))  /* value was collected? */
+        setnilvalue(o);  /* remove value */
     }
-    i = sizenode(h);
-    while (i--) {
-      Node *n = gnode(h, i);
+    for (n = gnode(h, 0); n < limit; n++) {
       if (!ttisnil(gval(n)) &&  /* non-empty entry? */
-          (iscleared(key2tval(n), 1) || iscleared(gval(n), 0))) {
+          (iscleared(gkey(n), 1) || iscleared(gval(n), 0))) {
         setnilvalue(gval(n));  /* remove value ... */
-        removeentry(n);  /* remove entry from table */
+        removeentry(n);  /* and remove entry from table */
       }
     }
-    l = h->gclist;
   }
 }
 
 
 static void freeobj (lua_State *L, GCObject *o) {
-  switch (o->gch.tt) {
+  switch (gch(o)->tt) {
     case LUA_TPROTO: luaF_freeproto(L, gco2p(o)); break;
     case LUA_TFUNCTION: luaF_freeclosure(L, gco2cl(o)); break;
     case LUA_TUPVAL: luaF_freeupval(L, gco2uv(o)); break;
-    case LUA_TTABLE: luaH_free(L, gco2h(o)); break;
-    case LUA_TTHREAD: {
-      lua_assert(gco2th(o) != L && gco2th(o) != G(L)->mainthread);
-      luaE_freethread(L, gco2th(o));
-      break;
-    }
+    case LUA_TTABLE: luaH_free(L, gco2t(o)); break;
+    case LUA_TTHREAD: luaE_freethread(L, gco2th(o)); break;
+    case LUA_TUSERDATA: luaM_freemem(L, o, sizeudata(gco2u(o))); break;
     case LUA_TSTRING: {
       G(L)->strt.nuse--;
       luaM_freemem(L, o, sizestring(gco2ts(o)));
       break;
     }
-    case LUA_TUSERDATA: {
-      luaM_freemem(L, o, sizeudata(gco2u(o)));
-      break;
-    }
     default: lua_assert(0);
   }
 }
 
 
-
 #define sweepwholelist(L,p)	sweeplist(L,p,MAX_LUMEM)
+static GCObject **sweeplist (lua_State *L, GCObject **p, lu_mem count);
 
 
+/*
+** sweep the (open) upvalues of a thread and resize its stack and
+** list of call-info structures.
+*/
+static void sweepthread (lua_State *L, lua_State *L1) {
+  if (L1->stack == NULL) return;  /* stack not completely built yet */
+  sweepwholelist(L, &L1->openupval);  /* sweep open upvalues */
+  luaE_freeCI(L1);  /* free extra CallInfo slots */
+  /* should not change the stack during an emergency gc cycle */
+  if (G(L)->gckind != KGC_EMERGENCY)
+    luaD_shrinkstack(L1);
+}
+
+
+/*
+** sweep at most 'count' elements from a list of GCObjects erasing dead
+** objects, where a dead (not alive) object is one marked with the "old"
+** (non current) white and not fixed.
+** In non-generational mode, change all non-dead objects back to white,
+** preparing for next collection cycle.
+** In generational mode, keep black objects black, and also mark them as
+** old; stop when hitting an old object, as all objects after that
+** one will be old too.
+** When object is a thread, sweep its list of open upvalues too.
+*/
 static GCObject **sweeplist (lua_State *L, GCObject **p, lu_mem count) {
-  GCObject *curr;
   global_State *g = G(L);
-  int deadmask = otherwhite(g);
-  while ((curr = *p) != NULL && count-- > 0) {
-    if (curr->gch.tt == LUA_TTHREAD)  /* sweep open upvalues of each thread */
-      sweepwholelist(L, &gco2th(curr)->openupval);
-    if ((curr->gch.marked ^ WHITEBITS) & deadmask) {  /* not dead? */
-      lua_assert(!isdead(g, curr) || testbit(curr->gch.marked, FIXEDBIT));
-      makewhite(g, curr);  /* make it white (for next cycle) */
-      p = &curr->gch.next;
+  int ow = otherwhite(g);
+  int toclear, toset;  /* bits to clear and to set in all live objects */
+  int tostop;  /* stop sweep when this is true */
+  l_mem debt = g->GCdebt;  /* current debt */
+  if (isgenerational(g)) {  /* generational mode? */
+    toclear = ~0;  /* clear nothing */
+    toset = bitmask(OLDBIT);  /* set the old bit of all surviving objects */
+    tostop = bitmask(OLDBIT);  /* do not sweep old generation */
+  }
+  else {  /* normal mode */
+    toclear = maskcolors;  /* clear all color bits + old bit */
+    toset = luaC_white(g);  /* make object white */
+    tostop = 0;  /* do not stop */
+  }
+  while (*p != NULL && count-- > 0) {
+    GCObject *curr = *p;
+    int marked = gch(curr)->marked;
+    if (isdeadm(ow, marked)) {  /* is 'curr' dead? */
+      *p = gch(curr)->next;  /* remove 'curr' from list */
+      freeobj(L, curr);  /* erase 'curr' */
     }
-    else {  /* must erase `curr' */
-      lua_assert(isdead(g, curr) || deadmask == bitmask(SFIXEDBIT));
-      *p = curr->gch.next;
-      if (curr == g->rootgc)  /* is the first element of the list? */
-        g->rootgc = curr->gch.next;  /* adjust first */
-      freeobj(L, curr);
+    else {
+      if (gch(curr)->tt == LUA_TTHREAD)
+        sweepthread(L, gco2th(curr));  /* sweep thread's upvalues */
+      if (testbits(marked, tostop)) {
+        static GCObject *nullp = NULL;
+        p = &nullp;  /* stop sweeping this list */
+        break;
+      }
+      /* update marks */
+      gch(curr)->marked = cast_byte((marked & toclear) | toset);
+      p = &gch(curr)->next;  /* go to next element */
     }
   }
+  luaE_setdebt(g, debt);  /* sweeping should not change debt */
   return p;
 }
 
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Finalization
+** =======================================================
+*/
 
 static void checkSizes (lua_State *L) {
   global_State *g = G(L);
-  /* check size of string hash */
-  if (g->strt.nuse < cast(lu_int32, g->strt.size/4) &&
-      g->strt.size > MINSTRTABSIZE*2)
-    luaS_resize(L, g->strt.size/2);  /* table is too big */
-  /* check size of buffer */
-  if (luaZ_sizebuffer(&g->buff) > LUA_MINBUFFER*2) {  /* buffer too big? */
-    size_t newsize = luaZ_sizebuffer(&g->buff) / 2;
-    luaZ_resizebuffer(L, &g->buff, newsize);
+  if (g->gckind != KGC_EMERGENCY) {  /* do not change sizes in emergency */
+    int hs = g->strt.size / 2;  /* half the size of the string table */
+    if (g->strt.nuse < cast(lu_int32, hs))  /* using less than that half? */
+      luaS_resize(L, hs);  /* halve its size */
+    luaZ_freebuffer(L, &g->buff);  /* free concatenation buffer */
   }
 }
 
 
-static void GCTM (lua_State *L) {
+static GCObject *udata2finalize (global_State *g) {
+  GCObject *o = g->tobefnz;  /* get first element */
+  lua_assert(isfinalized(o));
+  g->tobefnz = gch(o)->next;  /* remove it from 'tobefnz' list */
+  gch(o)->next = g->allgc;  /* return it to 'allgc' list */
+  g->allgc = o;
+  resetbit(gch(o)->marked, SEPARATED);  /* mark that it is not in 'tobefnz' */
+  lua_assert(!isold(o));  /* see MOVE OLD rule */
+  if (!keepinvariant(g))  /* not keeping invariant? */
+    makewhite(g, o);  /* "sweep" object */
+  return o;
+}
+
+
+static void dothecall (lua_State *L, void *ud) {
+  UNUSED(ud);
+  luaD_call(L, L->top - 2, 0, 0);
+}
+
+
+static void GCTM (lua_State *L, int propagateerrors) {
   global_State *g = G(L);
-  GCObject *o = g->tmudata->gch.next;  /* get first element */
-  Udata *udata = rawgco2u(o);
   const TValue *tm;
-  /* remove udata from `tmudata' */
-  if (o == g->tmudata)  /* last element? */
-    g->tmudata = NULL;
-  else
-    g->tmudata->gch.next = udata->uv.next;
-  udata->uv.next = g->mainthread->next;  /* return it to `root' list */
-  g->mainthread->next = o;
-  makewhite(g, o);
-  tm = fasttm(L, udata->uv.metatable, TM_GC);
-  if (tm != NULL) {
+  TValue v;
+  setgcovalue(L, &v, udata2finalize(g));
+  tm = luaT_gettmbyobj(L, &v, TM_GC);
+  if (tm != NULL && ttisfunction(tm)) {  /* is there a finalizer? */
+    int status;
     lu_byte oldah = L->allowhook;
-    lu_mem oldt = g->GCthreshold;
+    int running  = g->gcrunning;
     L->allowhook = 0;  /* stop debug hooks during GC tag method */
-    g->GCthreshold = 2*g->totalbytes;  /* avoid GC steps */
-    setobj2s(L, L->top, tm);
-    setuvalue(L, L->top+1, udata);
-    L->top += 2;
-    luaD_call(L, L->top - 2, 0);
+    g->gcrunning = 0;  /* avoid GC steps */
+    setobj2s(L, L->top, tm);  /* push finalizer... */
+    setobj2s(L, L->top + 1, &v);  /* ... and its argument */
+    L->top += 2;  /* and (next line) call the finalizer */
+    status = luaD_pcall(L, dothecall, NULL, savestack(L, L->top - 2), 0);
     L->allowhook = oldah;  /* restore hooks */
-    g->GCthreshold = oldt;  /* restore threshold */
+    g->gcrunning = running;  /* restore state */
+    if (status != LUA_OK && propagateerrors) {  /* error while running __gc? */
+      if (status == LUA_ERRRUN) {  /* is there an error msg.? */
+        luaO_pushfstring(L, "error in __gc tag method (%s)",
+                                        lua_tostring(L, -1));
+        status = LUA_ERRGCMM;  /* error in __gc metamethod */
+      }
+      luaD_throw(L, status);  /* re-send error */
+    }
   }
 }
 
 
 /*
-** Call all GC tag methods
+** move all unreachable objects that need finalization from list 'finobj'
+** to list 'tobefnz'
 */
-void luaC_callGCTM (lua_State *L) {
-  while (G(L)->tmudata)
-    GCTM(L);
+void luaC_separateudata (lua_State *L, int all) {
+  global_State *g = G(L);
+  GCObject **p = &g->finobj;
+  GCObject *curr;
+  GCObject **lastnext = &g->tobefnz;
+  /* find last 'next' field in 'tobefnz' list (to add elements in its end) */
+  while (*lastnext != NULL)
+    lastnext = &gch(*lastnext)->next;
+  while ((curr = *p) != NULL) {  /* traverse all finalizable objects */
+    lua_assert(!isfinalized(curr));
+    lua_assert(testbit(gch(curr)->marked, SEPARATED));
+    if (!(all || iswhite(curr)))  /* not being collected? */
+      p = &gch(curr)->next;  /* don't bother with it */
+    else {
+      l_setbit(gch(curr)->marked, FINALIZEDBIT); /* won't be finalized again */
+      *p = gch(curr)->next;  /* remove 'curr' from 'finobj' list */
+      gch(curr)->next = *lastnext;  /* link at the end of 'tobefnz' list */
+      *lastnext = curr;
+      lastnext = &gch(curr)->next;
+    }
+  }
 }
 
 
-void luaC_freeall (lua_State *L) {
+/*
+** if object 'o' has a finalizer, remove it from 'allgc' list (must
+** search the list to find it) and link it in 'finobj' list.
+*/
+void luaC_checkfinalizer (lua_State *L, GCObject *o, Table *mt) {
   global_State *g = G(L);
-  int i;
-  g->currentwhite = WHITEBITS | bitmask(SFIXEDBIT);  /* mask to collect all elements */
-  sweepwholelist(L, &g->rootgc);
-  for (i = 0; i < g->strt.size; i++)  /* free all string lists */
-    sweepwholelist(L, &g->strt.hash[i]);
+  if (testbit(gch(o)->marked, SEPARATED) || /* obj. is already separated... */
+      isfinalized(o) ||                           /* ... or is finalized... */
+      gfasttm(g, mt, TM_GC) == NULL)                /* or has no finalizer? */
+    return;  /* nothing to be done */
+  else {  /* move 'o' to 'finobj' list */
+    GCObject **p;
+    for (p = &g->allgc; *p != o; p = &gch(*p)->next) ;
+    *p = gch(o)->next;  /* remove 'o' from root list */
+    gch(o)->next = g->finobj;  /* link it in list 'finobj' */
+    g->finobj = o;
+    l_setbit(gch(o)->marked, SEPARATED);  /* mark it as such */
+    resetoldbit(o);  /* see MOVE OLD rule */
+  }
 }
 
+/* }====================================================== */
 
-static void markmt (global_State *g) {
-  int i;
-  for (i=0; i<NUM_TAGS; i++)
-    if (g->mt[i]) markobject(g, g->mt[i]);
-}
 
+/*
+** {======================================================
+** GC control
+** =======================================================
+*/
 
-/* mark root set */
-static void markroot (lua_State *L) {
+
+#define sweepphases  \
+	(bitmask(GCSsweepstring) | bitmask(GCSsweepudata) | bitmask(GCSsweep))
+
+/*
+** change GC mode
+*/
+void luaC_changemode (lua_State *L, int mode) {
   global_State *g = G(L);
-  g->gray = NULL;
-  g->grayagain = NULL;
-  g->weak = NULL;
-  markobject(g, g->mainthread);
-  /* make global table be traversed before main stack */
-  markvalue(g, gt(g->mainthread));
-  markvalue(g, registry(L));
-  markmt(g);
-  g->gcstate = GCSpropagate;
+  if (mode == g->gckind) return;  /* nothing to change */
+  if (mode == KGC_GEN) {  /* change to generational mode */
+    /* make sure gray lists are consistent */
+    luaC_runtilstate(L, bitmask(GCSpropagate));
+    g->lastmajormem = gettotalbytes(g);
+    g->gckind = KGC_GEN;
+  }
+  else {  /* change to incremental mode */
+    /* sweep all objects to turn them back to white
+       (as white has not changed, nothing extra will be collected) */
+    g->sweepstrgc = 0;
+    g->gcstate = GCSsweepstring;
+    g->gckind = KGC_NORMAL;
+    luaC_runtilstate(L, ~sweepphases);
+  }
 }
 
 
-static void remarkupvals (global_State *g) {
-  UpVal *uv;
-  for (uv = g->uvhead.u.l.next; uv != &g->uvhead; uv = uv->u.l.next) {
-    lua_assert(uv->u.l.next->u.l.prev == uv && uv->u.l.prev->u.l.next == uv);
-    if (isgray(obj2gco(uv)))
-      markvalue(g, uv->v);
+/*
+** call all pending finalizers
+*/
+static void callallpendingfinalizers (lua_State *L, int propagateerrors) {
+  global_State *g = G(L);
+  while (g->tobefnz) {
+    resetoldbit(g->tobefnz);
+    GCTM(L, propagateerrors);
   }
 }
 
 
+void luaC_freeallobjects (lua_State *L) {
+  global_State *g = G(L);
+  int i;
+  callallpendingfinalizers(L, 0);
+  /* following "white" makes all objects look dead */
+  g->currentwhite = WHITEBITS;
+  g->gckind = KGC_NORMAL;
+  sweepwholelist(L, &g->finobj);
+  lua_assert(g->finobj == NULL);
+  sweepwholelist(L, &g->allgc);
+  lua_assert(g->allgc == NULL);
+  for (i = 0; i < g->strt.size; i++)  /* free all string lists */
+    sweepwholelist(L, &g->strt.hash[i]);
+  lua_assert(g->strt.nuse == 0);
+}
+
+
 static void atomic (lua_State *L) {
   global_State *g = G(L);
-  size_t udsize;  /* total size of userdata to be finalized */
-  /* remark occasional upvalues of (maybe) dead threads */
-  remarkupvals(g);
-  /* traverse objects cautch by write barrier and by 'remarkupvals' */
-  propagateall(g);
-  /* remark weak tables */
-  g->gray = g->weak;
-  g->weak = NULL;
   lua_assert(!iswhite(obj2gco(g->mainthread)));
   markobject(g, L);  /* mark running thread */
-  markmt(g);  /* mark basic metatables (again) */
-  propagateall(g);
-  /* remark gray again */
-  g->gray = g->grayagain;
-  g->grayagain = NULL;
+  /* registry and global metatables may be changed by API */
+  markvalue(g, &g->l_registry);
+  markmt(g);  /* mark basic metatables */
+  /* remark occasional upvalues of (maybe) dead threads */
+  remarkupvals(g);
+  /* traverse objects caught by write barrier and by 'remarkupvals' */
   propagateall(g);
-  udsize = luaC_separateudata(L, 0);  /* separate userdata to be finalized */
-  marktmu(g);  /* mark `preserved' userdata */
-  udsize += propagateall(g);  /* remark, to propagate `preserveness' */
-  cleartable(g->weak);  /* remove collected objects from weak tables */
-  /* flip current white */
-  g->currentwhite = cast_byte(otherwhite(g));
-  g->sweepstrgc = 0;
-  g->sweepgc = &g->rootgc;
+  traverselistofgrays(g, &g->weak);  /* remark weak tables */
+  traverselistofgrays(g, &g->ephemeron);  /* remark ephemeron tables */
+  traverselistofgrays(g, &g->grayagain);  /* remark gray again */
+  convergeephemerons(g);
+  /* at this point, all strongly accessible objects are marked. */
+  luaC_separateudata(L, 0);  /* separate userdata to be finalized */
+  markbeingfnz(g);  /* mark userdata that will be finalized */
+  propagateall(g);  /* remark, to propagate `preserveness' */
+  convergeephemerons(g);
+  /* remove collected objects from weak tables */
+  cleartable(g->weak);
+  cleartable(g->ephemeron);
+  cleartable(g->allweak);
+  g->sweepstrgc = 0;  /* prepare to sweep strings */
   g->gcstate = GCSsweepstring;
-  g->estimate = g->totalbytes - udsize;  /* first estimate */
+  g->currentwhite = cast_byte(otherwhite(g));  /* flip current white */
+  /*lua_checkmemory(L);*/
 }
 
 
 static l_mem singlestep (lua_State *L) {
   global_State *g = G(L);
-  /*lua_checkmemory(L);*/
   switch (g->gcstate) {
     case GCSpause: {
-      markroot(L);  /* start a new collection */
-      return 0;
+      if (!isgenerational(g))
+        markroot(g);  /* start a new collection */
+      /* in any case, root must be marked */
+      lua_assert(!iswhite(obj2gco(g->mainthread))
+              && !iswhite(gcvalue(&g->l_registry)));
+      g->gcstate = GCSpropagate;
+      return GCROOTCOST;
     }
     case GCSpropagate: {
       if (g->gray)
         return propagatemark(g);
       else {  /* no more `gray' objects */
-        atomic(L);  /* finish mark phase */
-        return 0;
+        g->gcstate = GCSatomic;  /* finish mark phase */
+        atomic(L);
+        return GCATOMICCOST;
       }
     }
     case GCSsweepstring: {
-      lu_mem old = g->totalbytes;
-      sweepwholelist(L, &g->strt.hash[g->sweepstrgc++]);
-      if (g->sweepstrgc >= g->strt.size)  /* nothing more to sweep? */
-        g->gcstate = GCSsweep;  /* end sweep-string phase */
-      lua_assert(old >= g->totalbytes);
-      g->estimate -= old - g->totalbytes;
-      return GCSWEEPCOST;
+      if (g->sweepstrgc < g->strt.size) {
+        sweepwholelist(L, &g->strt.hash[g->sweepstrgc++]);
+        return GCSWEEPCOST;
+      }
+      else {  /* no more strings to sweep */
+        g->sweepgc = &g->finobj;  /* prepare to sweep finalizable objects */
+        g->gcstate = GCSsweepudata;
+        return 0;
+      }
     }
-    case GCSsweep: {
-      lu_mem old = g->totalbytes;
-      g->sweepgc = sweeplist(L, g->sweepgc, GCSWEEPMAX);
-      if (*g->sweepgc == NULL) {  /* nothing more to sweep? */
-        checkSizes(L);
-        g->gcstate = GCSfinalize;  /* end sweep phase */
+    case GCSsweepudata: {
+      if (*g->sweepgc) {
+        g->sweepgc = sweeplist(L, g->sweepgc, GCSWEEPMAX);
+        return GCSWEEPMAX*GCSWEEPCOST;
+      }
+      else {
+        g->sweepgc = &g->allgc;  /* go to next phase */
+        g->gcstate = GCSsweep;
+        return GCSWEEPCOST;
       }
-      lua_assert(old >= g->totalbytes);
-      g->estimate -= old - g->totalbytes;
-      return GCSWEEPMAX*GCSWEEPCOST;
     }
-    case GCSfinalize: {
-      if (g->tmudata) {
-        GCTM(L);
-        if (g->estimate > GCFINALIZECOST)
-          g->estimate -= GCFINALIZECOST;
-        return GCFINALIZECOST;
+    case GCSsweep: {
+      if (*g->sweepgc) {
+        g->sweepgc = sweeplist(L, g->sweepgc, GCSWEEPMAX);
+        return GCSWEEPMAX*GCSWEEPCOST;
       }
       else {
-        g->gcstate = GCSpause;  /* end collection */
-        g->gcdept = 0;
-        return 0;
+        /* sweep main thread */
+        GCObject *mt = obj2gco(g->mainthread);
+        sweeplist(L, &mt, 1);
+        checkSizes(L);
+        g->gcstate = GCSpause;  /* finish collection */
+        return GCSWEEPCOST;
       }
     }
     default: lua_assert(0); return 0;
@@ -607,105 +949,99 @@ static l_mem singlestep (lua_State *L) {
 }
 
 
-void luaC_step (lua_State *L) {
+/*
+** advances the garbage collector until it reaches a state allowed
+** by 'statemask'
+*/
+void luaC_runtilstate (lua_State *L, int statesmask) {
   global_State *g = G(L);
-  l_mem lim = (GCSTEPSIZE/100) * g->gcstepmul;
-  if (lim == 0)
-    lim = (MAX_LUMEM-1)/2;  /* no limit */
-  g->gcdept += g->totalbytes - g->GCthreshold;
-  do {
-    lim -= singlestep(L);
-    if (g->gcstate == GCSpause)
-      break;
-  } while (lim > 0);
-  if (g->gcstate != GCSpause) {
-    if (g->gcdept < GCSTEPSIZE)
-      g->GCthreshold = g->totalbytes + GCSTEPSIZE;  /* - lim/g->gcstepmul;*/
-    else {
-      g->gcdept -= GCSTEPSIZE;
-      g->GCthreshold = g->totalbytes;
-    }
-  }
-  else {
-    lua_assert(g->totalbytes >= g->estimate);
-    setthreshold(g);
-  }
+  while (!testbit(statesmask, g->gcstate))
+    singlestep(L);
 }
 
 
-void luaC_fullgc (lua_State *L) {
+static void generationalcollection (lua_State *L) {
   global_State *g = G(L);
-  if (g->gcstate <= GCSpropagate) {
-    /* reset sweep marks to sweep all elements (returning them to white) */
-    g->sweepstrgc = 0;
-    g->sweepgc = &g->rootgc;
-    /* reset other collector lists */
-    g->gray = NULL;
-    g->grayagain = NULL;
-    g->weak = NULL;
-    g->gcstate = GCSsweepstring;
+  if (g->lastmajormem == 0) {  /* signal for another major collection? */
+    luaC_fullgc(L, 0);  /* perform a full regular collection */
+    g->lastmajormem = gettotalbytes(g);  /* update control */
   }
-  lua_assert(g->gcstate != GCSpause && g->gcstate != GCSpropagate);
-  /* finish any pending sweep phase */
-  while (g->gcstate != GCSfinalize) {
-    lua_assert(g->gcstate == GCSsweepstring || g->gcstate == GCSsweep);
-    singlestep(L);
-  }
-  markroot(L);
-  while (g->gcstate != GCSpause) {
-    singlestep(L);
+  else {
+    luaC_runtilstate(L, ~bitmask(GCSpause));  /* run complete cycle */
+    luaC_runtilstate(L, bitmask(GCSpause));
+    if (gettotalbytes(g) > g->lastmajormem/100 * g->gcmajorinc)
+      g->lastmajormem = 0;  /* signal for a major collection */
   }
-  setthreshold(g);
+  luaE_setdebt(g, stddebt(g));
 }
 
 
-void luaC_barrierf (lua_State *L, GCObject *o, GCObject *v) {
+static void step (lua_State *L) {
   global_State *g = G(L);
-  lua_assert(isblack(o) && iswhite(v) && !isdead(g, v) && !isdead(g, o));
-  lua_assert(g->gcstate != GCSfinalize && g->gcstate != GCSpause);
-  lua_assert(ttype(&o->gch) != LUA_TTABLE);
-  /* must keep invariant? */
-  if (g->gcstate == GCSpropagate)
-    reallymarkobject(g, v);  /* restore invariant */
-  else  /* don't mind */
-    makewhite(g, o);  /* mark as white just to avoid other barriers */
+  l_mem lim = g->gcstepmul;  /* how much to work */
+  do {  /* always perform at least one single step */
+    lim -= singlestep(L);
+  } while (lim > 0 && g->gcstate != GCSpause);
+  if (g->gcstate != GCSpause)
+    luaE_setdebt(g, g->GCdebt - GCSTEPSIZE);
+  else
+    luaE_setdebt(g, stddebt(g));
 }
 
 
-void luaC_barrierback (lua_State *L, Table *t) {
+/*
+** performs a basic GC step even if the collector is stopped
+*/
+void luaC_forcestep (lua_State *L) {
   global_State *g = G(L);
-  GCObject *o = obj2gco(t);
-  lua_assert(isblack(o) && !isdead(g, o));
-  lua_assert(g->gcstate != GCSfinalize && g->gcstate != GCSpause);
-  black2gray(o);  /* make table gray (again) */
-  t->gclist = g->grayagain;
-  g->grayagain = o;
+  int i;
+  if (isgenerational(g)) generationalcollection(L);
+  else step(L);
+  for (i = 0; i < GCFINALIZENUM && g->tobefnz; i++)
+    GCTM(L, 1);  /* Call a few pending finalizers */
 }
 
 
-void luaC_link (lua_State *L, GCObject *o, lu_byte tt) {
-  global_State *g = G(L);
-  o->gch.next = g->rootgc;
-  g->rootgc = o;
-  o->gch.marked = luaC_white(g);
-  o->gch.tt = tt;
+/*
+** performs a basic GC step only if collector is running
+*/
+void luaC_step (lua_State *L) {
+  if (G(L)->gcrunning) luaC_forcestep(L);
 }
 
 
-void luaC_linkupval (lua_State *L, UpVal *uv) {
+/*
+** performs a full GC cycle; if "isemergency", does not call
+** finalizers (which could change stack positions)
+*/
+void luaC_fullgc (lua_State *L, int isemergency) {
   global_State *g = G(L);
-  GCObject *o = obj2gco(uv);
-  o->gch.next = g->rootgc;  /* link upvalue into `rootgc' list */
-  g->rootgc = o;
-  if (isgray(o)) { 
-    if (g->gcstate == GCSpropagate) {
-      gray2black(o);  /* closed upvalues need barrier */
-      luaC_barrier(L, uv, uv->v);
-    }
-    else {  /* sweep phase: sweep it (turning it into white) */
-      makewhite(g, o);
-      lua_assert(g->gcstate != GCSfinalize && g->gcstate != GCSpause);
-    }
+  int origkind = g->gckind;
+  lua_assert(origkind != KGC_EMERGENCY);
+  if (!isemergency)   /* do not run finalizers during emergency GC */
+    callallpendingfinalizers(L, 1);
+  if (keepinvariant(g)) {  /* marking phase? */
+    /* must sweep all objects to turn them back to white
+       (as white has not changed, nothing will be collected) */
+    g->sweepstrgc = 0;
+    g->gcstate = GCSsweepstring;
+  }
+  g->gckind = isemergency ? KGC_EMERGENCY : KGC_NORMAL;
+  /* finish any pending sweep phase to start a new cycle */
+  luaC_runtilstate(L, bitmask(GCSpause));
+  /* run entire collector */
+  luaC_runtilstate(L, ~bitmask(GCSpause));
+  luaC_runtilstate(L, bitmask(GCSpause));
+  if (origkind == KGC_GEN) {  /* generational mode? */
+    /* generational mode must always start in propagate phase */
+    luaC_runtilstate(L, bitmask(GCSpropagate));
   }
+  g->gckind = origkind;
+  luaE_setdebt(g, stddebt(g));
+  if (!isemergency)   /* do not run finalizers during emergency GC */
+    callallpendingfinalizers(L, 1);
 }
 
+/* }====================================================== */
+
+
diff --git a/src/lgc.h b/src/lgc.h
index 5a8dc60..0fae4dd 100644..100755
--- a/src/lgc.h
+++ b/src/lgc.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lgc.h,v 2.15.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lgc.h,v 2.50 2011/01/26 16:30:02 roberto Exp $
 ** Garbage Collector
 ** See Copyright Notice in lua.h
 */
@@ -9,65 +9,92 @@
 
 
 #include "lobject.h"
+#include "lstate.h"
+
+/*
+** Collectable objects may have one of three colors: white, which
+** means the object is not marked; gray, which means the
+** object is marked, but its references may be not marked; and
+** black, which means that the object and all its references are marked.
+** The main invariant of the garbage collector, while marking objects,
+** is that a black object can never point to a white one. Moreover,
+** any gray object must be in a "gray list" (gray, grayagain, weak,
+** allweak, ephemeron) so that it can be visited again before finishing
+** the collection cycle. These lists have no meaning when the invariant
+** is not being enforced (e.g., sweep phase).
+*/
 
 
 /*
 ** Possible states of the Garbage Collector
 */
-#define GCSpause	0
-#define GCSpropagate	1
+#define GCSpropagate	0
+#define GCSatomic	1
 #define GCSsweepstring	2
-#define GCSsweep	3
-#define GCSfinalize	4
+#define GCSsweepudata	3
+#define GCSsweep	4
+#define GCSpause	5
+
 
+#define issweepphase(g)  \
+	(GCSsweepstring <= (g)->gcstate && (g)->gcstate <= GCSsweep)
+
+#define isgenerational(g)	((g)->gckind == KGC_GEN)
 
 /*
-** some userful bit tricks
+** macro to tell when main invariant (white objects cannot point to black
+** ones) must be kept. During a non-generational collection, the sweep
+** phase may break the invariant, as objects turned white may point to
+** still-black objects. The invariant is restored when sweep ends and
+** all objects are white again. During a generational collection, the
+** invariant must be kept all times.
 */
-#define resetbits(x,m)	((x) &= cast(lu_byte, ~(m)))
-#define setbits(x,m)	((x) |= (m))
-#define testbits(x,m)	((x) & (m))
-#define bitmask(b)	(1<<(b))
-#define bit2mask(b1,b2)	(bitmask(b1) | bitmask(b2))
-#define l_setbit(x,b)	setbits(x, bitmask(b))
-#define resetbit(x,b)	resetbits(x, bitmask(b))
-#define testbit(x,b)	testbits(x, bitmask(b))
-#define set2bits(x,b1,b2)	setbits(x, (bit2mask(b1, b2)))
-#define reset2bits(x,b1,b2)	resetbits(x, (bit2mask(b1, b2)))
-#define test2bits(x,b1,b2)	testbits(x, (bit2mask(b1, b2)))
-
+#define keepinvariant(g)  (isgenerational(g) || g->gcstate <= GCSatomic)
 
 
 /*
-** Layout for bit use in `marked' field:
-** bit 0 - object is white (type 0)
-** bit 1 - object is white (type 1)
-** bit 2 - object is black
-** bit 3 - for userdata: has been finalized
-** bit 3 - for tables: has weak keys
-** bit 4 - for tables: has weak values
-** bit 5 - object is fixed (should not be collected)
-** bit 6 - object is "super" fixed (only the main thread)
+** some useful bit tricks
 */
+#define resetbits(x,m)		((x) &= cast(lu_byte, ~(m)))
+#define setbits(x,m)		((x) |= (m))
+#define testbits(x,m)		((x) & (m))
+#define bitmask(b)		(1<<(b))
+#define bit2mask(b1,b2)		(bitmask(b1) | bitmask(b2))
+#define l_setbit(x,b)		setbits(x, bitmask(b))
+#define resetbit(x,b)		resetbits(x, bitmask(b))
+#define testbit(x,b)		testbits(x, bitmask(b))
+#define set2bits(x,b1,b2)	setbits(x, (bit2mask(b1, b2)))
+#define reset2bits(x,b1,b2)	resetbits(x, (bit2mask(b1, b2)))
+
+
 
+/* Layout for bit use in `marked' field: */
+#define WHITE0BIT	0  /* object is white (type 0) */
+#define WHITE1BIT	1  /* object is white (type 1) */
+#define BLACKBIT	2  /* object is black */
+#define FINALIZEDBIT	3  /* object has been separated for finalization */
+#define SEPARATED	4  /* object is in 'finobj' list or in 'tobefnz' */
+#define FIXEDBIT	5  /* object is fixed (should not be collected) */
+#define OLDBIT		6  /* object is old (only in generational mode) */
+/* bit 7 is currently used by tests (luaL_checkmemory) */
 
-#define WHITE0BIT	0
-#define WHITE1BIT	1
-#define BLACKBIT	2
-#define FINALIZEDBIT	3
-#define KEYWEAKBIT	3
-#define VALUEWEAKBIT	4
-#define FIXEDBIT	5
-#define SFIXEDBIT	6
 #define WHITEBITS	bit2mask(WHITE0BIT, WHITE1BIT)
 
 
-#define iswhite(x)      test2bits((x)->gch.marked, WHITE0BIT, WHITE1BIT)
+#define iswhite(x)      testbits((x)->gch.marked, WHITEBITS)
 #define isblack(x)      testbit((x)->gch.marked, BLACKBIT)
-#define isgray(x)	(!isblack(x) && !iswhite(x))
+#define isgray(x)  /* neither white nor black */  \
+	(!testbits((x)->gch.marked, WHITEBITS | bitmask(BLACKBIT)))
+
+#define isold(x)	testbit((x)->gch.marked, OLDBIT)
+
+/* MOVE OLD rule: whenever an object is moved to the beginning of
+   a GC list, its old bit must be cleared */
+#define resetoldbit(o)	resetbit((o)->gch.marked, OLDBIT)
 
 #define otherwhite(g)	(g->currentwhite ^ WHITEBITS)
-#define isdead(g,v)	((v)->gch.marked & otherwhite(g) & WHITEBITS)
+#define isdeadm(ow,m)	(!(((m) ^ WHITEBITS) & (ow)))
+#define isdead(g,v)	isdeadm(otherwhite(g), (v)->gch.marked)
 
 #define changewhite(x)	((x)->gch.marked ^= WHITEBITS)
 #define gray2black(x)	l_setbit((x)->gch.marked, BLACKBIT)
@@ -77,34 +104,40 @@
 #define luaC_white(g)	cast(lu_byte, (g)->currentwhite & WHITEBITS)
 
 
-#define luaC_checkGC(L) { \
-  condhardstacktests(luaD_reallocstack(L, L->stacksize - EXTRA_STACK - 1)); \
-  if (G(L)->totalbytes >= G(L)->GCthreshold) \
-	luaC_step(L); }
+#define luaC_condGC(L,c) \
+	{if (G(L)->GCdebt > 0) {c;}; condchangemem(L);}
+#define luaC_checkGC(L)		luaC_condGC(L, luaC_step(L);)
 
 
 #define luaC_barrier(L,p,v) { if (valiswhite(v) && isblack(obj2gco(p)))  \
-	luaC_barrierf(L,obj2gco(p),gcvalue(v)); }
+	luaC_barrier_(L,obj2gco(p),gcvalue(v)); }
 
-#define luaC_barriert(L,t,v) { if (valiswhite(v) && isblack(obj2gco(t)))  \
-	luaC_barrierback(L,t); }
+#define luaC_barrierback(L,p,v) { if (valiswhite(v) && isblack(obj2gco(p)))  \
+	luaC_barrierback_(L,p); }
 
 #define luaC_objbarrier(L,p,o)  \
 	{ if (iswhite(obj2gco(o)) && isblack(obj2gco(p))) \
-		luaC_barrierf(L,obj2gco(p),obj2gco(o)); }
+		luaC_barrier_(L,obj2gco(p),obj2gco(o)); }
 
-#define luaC_objbarriert(L,t,o)  \
-   { if (iswhite(obj2gco(o)) && isblack(obj2gco(t))) luaC_barrierback(L,t); }
+#define luaC_objbarrierback(L,p,o)  \
+   { if (iswhite(obj2gco(o)) && isblack(obj2gco(p))) luaC_barrierback_(L,p); }
 
-LUAI_FUNC size_t luaC_separateudata (lua_State *L, int all);
-LUAI_FUNC void luaC_callGCTM (lua_State *L);
-LUAI_FUNC void luaC_freeall (lua_State *L);
-LUAI_FUNC void luaC_step (lua_State *L);
-LUAI_FUNC void luaC_fullgc (lua_State *L);
-LUAI_FUNC void luaC_link (lua_State *L, GCObject *o, lu_byte tt);
-LUAI_FUNC void luaC_linkupval (lua_State *L, UpVal *uv);
-LUAI_FUNC void luaC_barrierf (lua_State *L, GCObject *o, GCObject *v);
-LUAI_FUNC void luaC_barrierback (lua_State *L, Table *t);
+#define luaC_barrierproto(L,p,c) \
+   { if (isblack(obj2gco(p))) luaC_barrierproto_(L,p,c); }
 
+LUAI_FUNC void luaC_separateudata (lua_State *L, int all);
+LUAI_FUNC void luaC_freeallobjects (lua_State *L);
+LUAI_FUNC void luaC_step (lua_State *L);
+LUAI_FUNC void luaC_forcestep (lua_State *L);
+LUAI_FUNC void luaC_runtilstate (lua_State *L, int statesmask);
+LUAI_FUNC void luaC_fullgc (lua_State *L, int isemergency);
+LUAI_FUNC GCObject *luaC_newobj (lua_State *L, int tt, size_t sz,
+                                 GCObject **list, int offset);
+LUAI_FUNC void luaC_barrier_ (lua_State *L, GCObject *o, GCObject *v);
+LUAI_FUNC void luaC_barrierback_ (lua_State *L, GCObject *o);
+LUAI_FUNC void luaC_barrierproto_ (lua_State *L, Proto *p, Closure *c);
+LUAI_FUNC void luaC_checkfinalizer (lua_State *L, GCObject *o, Table *mt);
+LUAI_FUNC void luaC_checkupvalcolor (global_State *g, UpVal *uv);
+LUAI_FUNC void luaC_changemode (lua_State *L, int mode);
 
 #endif
diff --git a/src/linit.c b/src/linit.c
index c1f90df..8d3aa65 100644..100755
--- a/src/linit.c
+++ b/src/linit.c
@@ -1,10 +1,18 @@
 /*
-** $Id: linit.c,v 1.14.1.1 2007/12/27 13:02:25 roberto Exp $
-** Initialization of libraries for lua.c
+** $Id: linit.c,v 1.32 2011/04/08 19:17:36 roberto Exp $
+** Initialization of libraries for lua.c and other clients
 ** See Copyright Notice in lua.h
 */
 
 
+/*
+** If you embed Lua in your program and need to open the standard
+** libraries, call luaL_openlibs in your program. If you need a
+** different set of libraries, copy this file to your project and edit
+** it to suit your needs.
+*/
+
+
 #define linit_c
 #define LUA_LIB
 
@@ -14,25 +22,46 @@
 #include "lauxlib.h"
 
 
-static const luaL_Reg lualibs[] = {
-  {"", luaopen_base},
+/*
+** these libs are loaded by lua.c and are readily available to any Lua
+** program
+*/
+static const luaL_Reg loadedlibs[] = {
+  {"_G", luaopen_base},
   {LUA_LOADLIBNAME, luaopen_package},
+  {LUA_COLIBNAME, luaopen_coroutine},
   {LUA_TABLIBNAME, luaopen_table},
   {LUA_IOLIBNAME, luaopen_io},
   {LUA_OSLIBNAME, luaopen_os},
   {LUA_STRLIBNAME, luaopen_string},
+  {LUA_BITLIBNAME, luaopen_bit32},
   {LUA_MATHLIBNAME, luaopen_math},
   {LUA_DBLIBNAME, luaopen_debug},
   {NULL, NULL}
 };
 
 
+/*
+** these libs are preloaded and must be required before used
+*/
+static const luaL_Reg preloadedlibs[] = {
+  {NULL, NULL}
+};
+
+
 LUALIB_API void luaL_openlibs (lua_State *L) {
-  const luaL_Reg *lib = lualibs;
-  for (; lib->func; lib++) {
+  const luaL_Reg *lib;
+  /* call open functions from 'loadedlibs' and set results to global table */
+  for (lib = loadedlibs; lib->func; lib++) {
+    luaL_requiref(L, lib->name, lib->func, 1);
+    lua_pop(L, 1);  /* remove lib */
+  }
+  /* add open functions from 'preloadedlibs' into 'package.preload' table */
+  luaL_getsubtable(L, LUA_REGISTRYINDEX, "_PRELOAD");
+  for (lib = preloadedlibs; lib->func; lib++) {
     lua_pushcfunction(L, lib->func);
-    lua_pushstring(L, lib->name);
-    lua_call(L, 1, 0);
+    lua_setfield(L, -2, lib->name);
   }
+  lua_pop(L, 1);  /* remove _PRELOAD table */
 }
 
diff --git a/src/liolib.c b/src/liolib.c
index 649f9a5..41e7ec5 100644..100755
--- a/src/liolib.c
+++ b/src/liolib.c
@@ -1,5 +1,5 @@
 /*
-** $Id: liolib.c,v 2.73.1.4 2010/05/14 15:33:51 roberto Exp $
+** $Id: liolib.c,v 2.101 2011/06/27 19:42:31 roberto Exp $
 ** Standard I/O (and system) library
 ** See Copyright Notice in lua.h
 */
@@ -20,29 +20,44 @@
 
 
 
-#define IO_INPUT	1
-#define IO_OUTPUT	2
+/*
+** lua_popen spawns a new process connected to the current one through
+** the file streams.
+*/
+#if !defined(lua_popen)	/* { */
 
+#if defined(LUA_USE_POPEN)	/* { */
 
-static const char *const fnames[] = {"input", "output"};
+#define lua_popen(L,c,m)	((void)L, fflush(NULL), popen(c,m))
+#define lua_pclose(L,file)	((void)L, pclose(file))
 
+#elif defined(LUA_WIN)		/* }{ */
 
-static int pushresult (lua_State *L, int i, const char *filename) {
-  int en = errno;  /* calls to Lua API may change this value */
-  if (i) {
-    lua_pushboolean(L, 1);
-    return 1;
-  }
-  else {
-    lua_pushnil(L);
-    if (filename)
-      lua_pushfstring(L, "%s: %s", filename, strerror(en));
-    else
-      lua_pushfstring(L, "%s", strerror(en));
-    lua_pushinteger(L, en);
-    return 3;
-  }
-}
+#define lua_popen(L,c,m)		((void)L, _popen(c,m))
+#define lua_pclose(L,file)		((void)L, _pclose(file))
+
+
+#else				/* }{ */
+
+#define lua_popen(L,c,m)		((void)((void)c, m),  \
+		luaL_error(L, LUA_QL("popen") " not supported"), (FILE*)0)
+#define lua_pclose(L,file)		((void)((void)L, file), -1)
+
+
+#endif				/* } */
+
+#endif			/* } */
+
+
+#define IO_PREFIX	"_IO_"
+#define IO_INPUT	(IO_PREFIX "input")
+#define IO_OUTPUT	(IO_PREFIX "output")
+
+
+typedef struct LStream {
+  FILE *f;  /* stream */
+  lua_CFunction closef;  /* to close stream (NULL for closed streams) */
+} LStream;
 
 
 static void fileerror (lua_State *L, int arg, const char *filename) {
@@ -51,17 +66,18 @@ static void fileerror (lua_State *L, int arg, const char *filename) {
 }
 
 
-#define tofilep(L)	((FILE **)luaL_checkudata(L, 1, LUA_FILEHANDLE))
+#define tolstream(L)	((LStream *)luaL_checkudata(L, 1, LUA_FILEHANDLE))
+
+#define isclosed(p)	((p)->closef == NULL)
 
 
 static int io_type (lua_State *L) {
-  void *ud;
+  LStream *p;
   luaL_checkany(L, 1);
-  ud = lua_touserdata(L, 1);
-  lua_getfield(L, LUA_REGISTRYINDEX, LUA_FILEHANDLE);
-  if (ud == NULL || !lua_getmetatable(L, 1) || !lua_rawequal(L, -2, -1))
+  p = (LStream *)luaL_testudata(L, 1, LUA_FILEHANDLE);
+  if (p == NULL)
     lua_pushnil(L);  /* not a file */
-  else if (*((FILE **)ud) == NULL)
+  else if (isclosed(p))
     lua_pushliteral(L, "closed file");
   else
     lua_pushliteral(L, "file");
@@ -69,151 +85,150 @@ static int io_type (lua_State *L) {
 }
 
 
+static int f_tostring (lua_State *L) {
+  LStream *p = tolstream(L);
+  if (isclosed(p))
+    lua_pushliteral(L, "file (closed)");
+  else
+    lua_pushfstring(L, "file (%p)", p->f);
+  return 1;
+}
+
+
 static FILE *tofile (lua_State *L) {
-  FILE **f = tofilep(L);
-  if (*f == NULL)
+  LStream *p = tolstream(L);
+  if (isclosed(p))
     luaL_error(L, "attempt to use a closed file");
-  return *f;
+  lua_assert(p->f);
+  return p->f;
 }
 
 
-
 /*
 ** When creating file handles, always creates a `closed' file handle
 ** before opening the actual file; so, if there is a memory error, the
 ** file is not left opened.
 */
-static FILE **newfile (lua_State *L) {
-  FILE **pf = (FILE **)lua_newuserdata(L, sizeof(FILE *));
-  *pf = NULL;  /* file handle is currently `closed' */
-  luaL_getmetatable(L, LUA_FILEHANDLE);
-  lua_setmetatable(L, -2);
-  return pf;
-}
-
-
-/*
-** function to (not) close the standard files stdin, stdout, and stderr
-*/
-static int io_noclose (lua_State *L) {
-  lua_pushnil(L);
-  lua_pushliteral(L, "cannot close standard file");
-  return 2;
-}
-
-
-/*
-** function to close 'popen' files
-*/
-static int io_pclose (lua_State *L) {
-  FILE **p = tofilep(L);
-  int ok = lua_pclose(L, *p);
-  *p = NULL;
-  return pushresult(L, ok, NULL);
-}
-
-
-/*
-** function to close regular files
-*/
-static int io_fclose (lua_State *L) {
-  FILE **p = tofilep(L);
-  int ok = (fclose(*p) == 0);
-  *p = NULL;
-  return pushresult(L, ok, NULL);
+static LStream *newprefile (lua_State *L) {
+  LStream *p = (LStream *)lua_newuserdata(L, sizeof(LStream));
+  p->closef = NULL;  /* mark file handle as 'closed' */
+  luaL_setmetatable(L, LUA_FILEHANDLE);
+  return p;
 }
 
 
 static int aux_close (lua_State *L) {
-  lua_getfenv(L, 1);
-  lua_getfield(L, -1, "__close");
-  return (lua_tocfunction(L, -1))(L);
+  LStream *p = tolstream(L);
+  lua_CFunction cf = p->closef;
+  p->closef = NULL;  /* mark stream as closed */
+  return (*cf)(L);  /* close it */
 }
 
 
 static int io_close (lua_State *L) {
-  if (lua_isnone(L, 1))
-    lua_rawgeti(L, LUA_ENVIRONINDEX, IO_OUTPUT);
-  tofile(L);  /* make sure argument is a file */
+  if (lua_isnone(L, 1))  /* no argument? */
+    lua_getfield(L, LUA_REGISTRYINDEX, IO_OUTPUT);  /* use standard output */
+  tofile(L);  /* make sure argument is an open stream */
   return aux_close(L);
 }
 
 
-static int io_gc (lua_State *L) {
-  FILE *f = *tofilep(L);
-  /* ignore closed files */
-  if (f != NULL)
-    aux_close(L);
+static int f_gc (lua_State *L) {
+  LStream *p = tolstream(L);
+  if (!isclosed(p) && p->f != NULL)
+    aux_close(L);  /* ignore closed and incompletely open files */
   return 0;
 }
 
 
-static int io_tostring (lua_State *L) {
-  FILE *f = *tofilep(L);
-  if (f == NULL)
-    lua_pushliteral(L, "file (closed)");
-  else
-    lua_pushfstring(L, "file (%p)", f);
-  return 1;
+/*
+** function to close regular files
+*/
+static int io_fclose (lua_State *L) {
+  LStream *p = tolstream(L);
+  int res = fclose(p->f);
+  return luaL_fileresult(L, (res == 0), NULL);
+}
+
+
+static LStream *newfile (lua_State *L) {
+  LStream *p = newprefile(L);
+  p->f = NULL;
+  p->closef = &io_fclose;
+  return p;
 }
 
 
 static int io_open (lua_State *L) {
   const char *filename = luaL_checkstring(L, 1);
   const char *mode = luaL_optstring(L, 2, "r");
-  FILE **pf = newfile(L);
-  *pf = fopen(filename, mode);
-  return (*pf == NULL) ? pushresult(L, 0, filename) : 1;
+  LStream *p = newfile(L);
+  int i = 0;
+  /* check whether 'mode' matches '[rwa]%+?b?' */
+  if (!(mode[i] != '\0' && strchr("rwa", mode[i++]) != NULL &&
+       (mode[i] != '+' || ++i) &&  /* skip if char is '+' */
+       (mode[i] != 'b' || ++i) &&  /* skip if char is 'b' */
+       (mode[i] == '\0')))
+    return luaL_error(L, "invalid mode " LUA_QL("%s")
+                         " (should match " LUA_QL("[rwa]%%+?b?") ")", mode);
+  p->f = fopen(filename, mode);
+  return (p->f == NULL) ? luaL_fileresult(L, 0, filename) : 1;
 }
 
 
 /*
-** this function has a separated environment, which defines the
-** correct __close for 'popen' files
+** function to close 'popen' files
 */
+static int io_pclose (lua_State *L) {
+  LStream *p = tolstream(L);
+  return luaL_execresult(L, lua_pclose(L, p->f));
+}
+
+
 static int io_popen (lua_State *L) {
   const char *filename = luaL_checkstring(L, 1);
   const char *mode = luaL_optstring(L, 2, "r");
-  FILE **pf = newfile(L);
-  *pf = lua_popen(L, filename, mode);
-  return (*pf == NULL) ? pushresult(L, 0, filename) : 1;
+  LStream *p = newprefile(L);
+  p->f = lua_popen(L, filename, mode);
+  p->closef = &io_pclose;
+  return (p->f == NULL) ? luaL_fileresult(L, 0, filename) : 1;
 }
 
 
 static int io_tmpfile (lua_State *L) {
-  FILE **pf = newfile(L);
-  *pf = tmpfile();
-  return (*pf == NULL) ? pushresult(L, 0, NULL) : 1;
+  LStream *p = newfile(L);
+  p->f = tmpfile();
+  return (p->f == NULL) ? luaL_fileresult(L, 0, NULL) : 1;
 }
 
 
-static FILE *getiofile (lua_State *L, int findex) {
-  FILE *f;
-  lua_rawgeti(L, LUA_ENVIRONINDEX, findex);
-  f = *(FILE **)lua_touserdata(L, -1);
-  if (f == NULL)
-    luaL_error(L, "standard %s file is closed", fnames[findex - 1]);
-  return f;
+static FILE *getiofile (lua_State *L, const char *findex) {
+  LStream *p;
+  lua_getfield(L, LUA_REGISTRYINDEX, findex);
+  p = (LStream *)lua_touserdata(L, -1);
+  if (isclosed(p))
+    luaL_error(L, "standard %s file is closed", findex + strlen(IO_PREFIX));
+  return p->f;
 }
 
 
-static int g_iofile (lua_State *L, int f, const char *mode) {
+static int g_iofile (lua_State *L, const char *f, const char *mode) {
   if (!lua_isnoneornil(L, 1)) {
     const char *filename = lua_tostring(L, 1);
     if (filename) {
-      FILE **pf = newfile(L);
-      *pf = fopen(filename, mode);
-      if (*pf == NULL)
+      LStream *p = newfile(L);
+      p->f = fopen(filename, mode);
+      if (p->f == NULL)
         fileerror(L, 1, filename);
     }
     else {
       tofile(L);  /* check that it's a valid file handle */
       lua_pushvalue(L, 1);
     }
-    lua_rawseti(L, LUA_ENVIRONINDEX, f);
+    lua_setfield(L, LUA_REGISTRYINDEX, f);
   }
   /* return current value */
-  lua_rawgeti(L, LUA_ENVIRONINDEX, f);
+  lua_getfield(L, LUA_REGISTRYINDEX, f);
   return 1;
 }
 
@@ -231,35 +246,46 @@ static int io_output (lua_State *L) {
 static int io_readline (lua_State *L);
 
 
-static void aux_lines (lua_State *L, int idx, int toclose) {
-  lua_pushvalue(L, idx);
+static void aux_lines (lua_State *L, int toclose) {
+  int i;
+  int n = lua_gettop(L) - 1;  /* number of arguments to read */
+  /* ensure that arguments will fit here and into 'io_readline' stack */
+  luaL_argcheck(L, n <= LUA_MINSTACK - 3, LUA_MINSTACK - 3, "too many options");
+  lua_pushvalue(L, 1);  /* file handle */
+  lua_pushinteger(L, n);  /* number of arguments to read */
   lua_pushboolean(L, toclose);  /* close/not close file when finished */
-  lua_pushcclosure(L, io_readline, 2);
+  for (i = 1; i <= n; i++) lua_pushvalue(L, i + 1);  /* copy arguments */
+  lua_pushcclosure(L, io_readline, 3 + n);
 }
 
 
 static int f_lines (lua_State *L) {
   tofile(L);  /* check that it's a valid file handle */
-  aux_lines(L, 1, 0);
+  aux_lines(L, 0);
   return 1;
 }
 
 
 static int io_lines (lua_State *L) {
-  if (lua_isnoneornil(L, 1)) {  /* no arguments? */
-    /* will iterate over default input */
-    lua_rawgeti(L, LUA_ENVIRONINDEX, IO_INPUT);
-    return f_lines(L);
+  int toclose;
+  if (lua_isnone(L, 1)) lua_pushnil(L);  /* at least one argument */
+  if (lua_isnil(L, 1)) {  /* no file name? */
+    lua_getfield(L, LUA_REGISTRYINDEX, IO_INPUT);  /* get default input */
+    lua_replace(L, 1);  /* put it at index 1 */
+    tofile(L);  /* check that it's a valid file handle */
+    toclose = 0;  /* do not close it after iteration */
   }
-  else {
+  else {  /* open a new file */
     const char *filename = luaL_checkstring(L, 1);
-    FILE **pf = newfile(L);
-    *pf = fopen(filename, "r");
-    if (*pf == NULL)
+    LStream *p = newfile(L);
+    p->f = fopen(filename, "r");
+    if (p->f == NULL)
       fileerror(L, 1, filename);
-    aux_lines(L, lua_gettop(L), 1);
-    return 1;
+    lua_replace(L, 1);  /* put file at index 1 */
+    toclose = 1;  /* close it after iteration */
   }
+  aux_lines(L, toclose);
+  return 1;
 }
 
 
@@ -277,8 +303,8 @@ static int read_number (lua_State *L, FILE *f) {
     return 1;
   }
   else {
-    lua_pushnil(L);  /* "result" to be removed */
-    return 0;  /* read fails */
+   lua_pushnil(L);  /* "result" to be removed */
+   return 0;  /* read fails */
   }
 }
 
@@ -291,7 +317,7 @@ static int test_eof (lua_State *L, FILE *f) {
 }
 
 
-static int read_line (lua_State *L, FILE *f) {
+static int read_line (lua_State *L, FILE *f, int chop) {
   luaL_Buffer b;
   luaL_buffinit(L, &b);
   for (;;) {
@@ -299,13 +325,13 @@ static int read_line (lua_State *L, FILE *f) {
     char *p = luaL_prepbuffer(&b);
     if (fgets(p, LUAL_BUFFERSIZE, f) == NULL) {  /* eof? */
       luaL_pushresult(&b);  /* close buffer */
-      return (lua_objlen(L, -1) > 0);  /* check whether read something */
+      return (lua_rawlen(L, -1) > 0);  /* check whether read something */
     }
     l = strlen(p);
     if (l == 0 || p[l-1] != '\n')
       luaL_addsize(&b, l);
     else {
-      luaL_addsize(&b, l - 1);  /* do not include `eol' */
+      luaL_addsize(&b, l - chop);  /* chop 'eol' if needed */
       luaL_pushresult(&b);  /* close buffer */
       return 1;  /* read at least an `eol' */
     }
@@ -313,21 +339,34 @@ static int read_line (lua_State *L, FILE *f) {
 }
 
 
+#define MAX_SIZE_T	(~(size_t)0)
+
+static void read_all (lua_State *L, FILE *f) {
+  size_t rlen = LUAL_BUFFERSIZE;  /* how much to read in each cycle */
+  luaL_Buffer b;
+  luaL_buffinit(L, &b);
+  for (;;) {
+    char *p = luaL_prepbuffsize(&b, rlen);
+    size_t nr = fread(p, sizeof(char), rlen, f);
+    luaL_addsize(&b, nr);
+    if (nr < rlen) break;  /* eof? */
+    else if (rlen <= (MAX_SIZE_T / 4))  /* avoid buffers too large */
+      rlen *= 2;  /* double buffer size at each iteration */
+  }
+  luaL_pushresult(&b);  /* close buffer */
+}
+
+
 static int read_chars (lua_State *L, FILE *f, size_t n) {
-  size_t rlen;  /* how much to read */
   size_t nr;  /* number of chars actually read */
+  char *p;
   luaL_Buffer b;
   luaL_buffinit(L, &b);
-  rlen = LUAL_BUFFERSIZE;  /* try to read that much each time */
-  do {
-    char *p = luaL_prepbuffer(&b);
-    if (rlen > n) rlen = n;  /* cannot read more than asked */
-    nr = fread(p, sizeof(char), rlen, f);
-    luaL_addsize(&b, nr);
-    n -= nr;  /* still have to read `n' chars */
-  } while (n > 0 && nr == rlen);  /* until end of count or eof */
+  p = luaL_prepbuffsize(&b, n);  /* prepare buffer to read whole block */
+  nr = fread(p, sizeof(char), n, f);  /* try to read 'n' chars */
+  luaL_addsize(&b, nr);
   luaL_pushresult(&b);  /* close buffer */
-  return (n == 0 || lua_objlen(L, -1) > 0);
+  return (nr > 0);  /* true iff read something */
 }
 
 
@@ -337,7 +376,7 @@ static int g_read (lua_State *L, FILE *f, int first) {
   int n;
   clearerr(f);
   if (nargs == 0) {  /* no arguments? */
-    success = read_line(L, f);
+    success = read_line(L, f, 1);
     n = first+1;  /* to return 1 result */
   }
   else {  /* ensure stack space for all results and for auxlib's buffer */
@@ -356,10 +395,13 @@ static int g_read (lua_State *L, FILE *f, int first) {
             success = read_number(L, f);
             break;
           case 'l':  /* line */
-            success = read_line(L, f);
+            success = read_line(L, f, 1);
+            break;
+          case 'L':  /* line with end-of-line */
+            success = read_line(L, f, 0);
             break;
           case 'a':  /* file */
-            read_chars(L, f, ~((size_t)0));  /* read MAX_SIZE_T chars */
+            read_all(L, f);  /* read entire file */
             success = 1; /* always success */
             break;
           default:
@@ -369,7 +411,7 @@ static int g_read (lua_State *L, FILE *f, int first) {
     }
   }
   if (ferror(f))
-    return pushresult(L, 0, NULL);
+    return luaL_fileresult(L, 0, NULL);
   if (!success) {
     lua_pop(L, 1);  /* remove last result */
     lua_pushnil(L);  /* push nil instead */
@@ -389,16 +431,23 @@ static int f_read (lua_State *L) {
 
 
 static int io_readline (lua_State *L) {
-  FILE *f = *(FILE **)lua_touserdata(L, lua_upvalueindex(1));
-  int sucess;
-  if (f == NULL)  /* file is already closed? */
-    luaL_error(L, "file is already closed");
-  sucess = read_line(L, f);
-  if (ferror(f))
-    return luaL_error(L, "%s", strerror(errno));
-  if (sucess) return 1;
-  else {  /* EOF */
-    if (lua_toboolean(L, lua_upvalueindex(2))) {  /* generator created file? */
+  LStream *p = (LStream *)lua_touserdata(L, lua_upvalueindex(1));
+  int i;
+  int n = (int)lua_tointeger(L, lua_upvalueindex(2));
+  if (isclosed(p))  /* file is already closed? */
+    return luaL_error(L, "file is already closed");
+  lua_settop(L , 1);
+  for (i = 1; i <= n; i++)  /* push arguments to 'g_read' */
+    lua_pushvalue(L, lua_upvalueindex(3 + i));
+  n = g_read(L, p->f, 2);  /* 'n' is number of results */
+  lua_assert(n > 0);  /* should return at least a nil */
+  if (!lua_isnil(L, -n))  /* read at least one value? */
+    return n;  /* return them */
+  else {  /* first result is nil: EOF or error */
+    if (!lua_isnil(L, -1))  /* is there error information? */
+      return luaL_error(L, "%s", lua_tostring(L, -1));  /* error */
+    /* else EOF */
+    if (lua_toboolean(L, lua_upvalueindex(3))) {  /* generator created file? */
       lua_settop(L, 0);
       lua_pushvalue(L, lua_upvalueindex(1));
       aux_close(L);  /* close it */
@@ -411,7 +460,7 @@ static int io_readline (lua_State *L) {
 
 
 static int g_write (lua_State *L, FILE *f, int arg) {
-  int nargs = lua_gettop(L) - 1;
+  int nargs = lua_gettop(L) - arg;
   int status = 1;
   for (; nargs--; arg++) {
     if (lua_type(L, arg) == LUA_TNUMBER) {
@@ -425,7 +474,8 @@ static int g_write (lua_State *L, FILE *f, int arg) {
       status = status && (fwrite(s, sizeof(char), l, f) == l);
     }
   }
-  return pushresult(L, status, NULL);
+  if (status) return 1;  /* file handle already on stack top */
+  else return luaL_fileresult(L, status, NULL);
 }
 
 
@@ -435,7 +485,9 @@ static int io_write (lua_State *L) {
 
 
 static int f_write (lua_State *L) {
-  return g_write(L, tofile(L), 2);
+  FILE *f = tofile(L);
+  lua_pushvalue(L, 1);  /* push file at the stack top (to be returned) */
+  return g_write(L, f, 2);
 }
 
 
@@ -447,7 +499,7 @@ static int f_seek (lua_State *L) {
   long offset = luaL_optlong(L, 3, 0);
   op = fseek(f, offset, mode[op]);
   if (op)
-    return pushresult(L, 0, NULL);  /* error */
+    return luaL_fileresult(L, 0, NULL);  /* error */
   else {
     lua_pushinteger(L, ftell(f));
     return 1;
@@ -462,21 +514,24 @@ static int f_setvbuf (lua_State *L) {
   int op = luaL_checkoption(L, 2, NULL, modenames);
   lua_Integer sz = luaL_optinteger(L, 3, LUAL_BUFFERSIZE);
   int res = setvbuf(f, NULL, mode[op], sz);
-  return pushresult(L, res == 0, NULL);
+  return luaL_fileresult(L, res == 0, NULL);
 }
 
 
 
 static int io_flush (lua_State *L) {
-  return pushresult(L, fflush(getiofile(L, IO_OUTPUT)) == 0, NULL);
+  return luaL_fileresult(L, fflush(getiofile(L, IO_OUTPUT)) == 0, NULL);
 }
 
 
 static int f_flush (lua_State *L) {
-  return pushresult(L, fflush(tofile(L)) == 0, NULL);
+  return luaL_fileresult(L, fflush(tofile(L)) == 0, NULL);
 }
 
 
+/*
+** functions for 'io' library
+*/
 static const luaL_Reg iolib[] = {
   {"close", io_close},
   {"flush", io_flush},
@@ -493,6 +548,9 @@ static const luaL_Reg iolib[] = {
 };
 
 
+/*
+** methods for file handles
+*/
 static const luaL_Reg flib[] = {
   {"close", io_close},
   {"flush", f_flush},
@@ -501,8 +559,8 @@ static const luaL_Reg flib[] = {
   {"seek", f_seek},
   {"setvbuf", f_setvbuf},
   {"write", f_write},
-  {"__gc", io_gc},
-  {"__tostring", io_tostring},
+  {"__gc", f_gc},
+  {"__tostring", f_tostring},
   {NULL, NULL}
 };
 
@@ -511,46 +569,43 @@ static void createmeta (lua_State *L) {
   luaL_newmetatable(L, LUA_FILEHANDLE);  /* create metatable for file handles */
   lua_pushvalue(L, -1);  /* push metatable */
   lua_setfield(L, -2, "__index");  /* metatable.__index = metatable */
-  luaL_register(L, NULL, flib);  /* file methods */
+  luaL_setfuncs(L, flib, 0);  /* add file methods to new metatable */
+  lua_pop(L, 1);  /* pop new metatable */
 }
 
 
-static void createstdfile (lua_State *L, FILE *f, int k, const char *fname) {
-  *newfile(L) = f;
-  if (k > 0) {
-    lua_pushvalue(L, -1);
-    lua_rawseti(L, LUA_ENVIRONINDEX, k);
-  }
-  lua_pushvalue(L, -2);  /* copy environment */
-  lua_setfenv(L, -2);  /* set it */
-  lua_setfield(L, -3, fname);
+/*
+** function to (not) close the standard files stdin, stdout, and stderr
+*/
+static int io_noclose (lua_State *L) {
+  LStream *p = tolstream(L);
+  p->closef = &io_noclose;  /* keep file opened */
+  lua_pushnil(L);
+  lua_pushliteral(L, "cannot close standard file");
+  return 2;
 }
 
 
-static void newfenv (lua_State *L, lua_CFunction cls) {
-  lua_createtable(L, 0, 1);
-  lua_pushcfunction(L, cls);
-  lua_setfield(L, -2, "__close");
+static void createstdfile (lua_State *L, FILE *f, const char *k,
+                           const char *fname) {
+  LStream *p = newprefile(L);
+  p->f = f;
+  p->closef = &io_noclose;
+  if (k != NULL) {
+    lua_pushvalue(L, -1);
+    lua_setfield(L, LUA_REGISTRYINDEX, k);  /* add file to registry */
+  }
+  lua_setfield(L, -2, fname);  /* add file to module */
 }
 
 
-LUALIB_API int luaopen_io (lua_State *L) {
+LUAMOD_API int luaopen_io (lua_State *L) {
+  luaL_newlib(L, iolib);  /* new module */
   createmeta(L);
-  /* create (private) environment (with fields IO_INPUT, IO_OUTPUT, __close) */
-  newfenv(L, io_fclose);
-  lua_replace(L, LUA_ENVIRONINDEX);
-  /* open library */
-  luaL_register(L, LUA_IOLIBNAME, iolib);
   /* create (and set) default files */
-  newfenv(L, io_noclose);  /* close function for default files */
   createstdfile(L, stdin, IO_INPUT, "stdin");
   createstdfile(L, stdout, IO_OUTPUT, "stdout");
-  createstdfile(L, stderr, 0, "stderr");
-  lua_pop(L, 1);  /* pop environment for default files */
-  lua_getfield(L, -1, "popen");
-  newfenv(L, io_pclose);  /* create environment for 'popen' */
-  lua_setfenv(L, -2);  /* set fenv for 'popen' */
-  lua_pop(L, 1);  /* pop 'popen' */
+  createstdfile(L, stderr, NULL, "stderr");
   return 1;
 }
 
diff --git a/src/llex.c b/src/llex.c
index 88c6790..289abfd 100644..100755
--- a/src/llex.c
+++ b/src/llex.c
@@ -1,11 +1,10 @@
 /*
-** $Id: llex.c,v 2.20.1.2 2009/11/23 14:58:22 roberto Exp $
+** $Id: llex.c,v 2.53 2011/07/08 20:01:38 roberto Exp $
 ** Lexical Analyzer
 ** See Copyright Notice in lua.h
 */
 
 
-#include <ctype.h>
 #include <locale.h>
 #include <string.h>
 
@@ -14,6 +13,7 @@
 
 #include "lua.h"
 
+#include "lctype.h"
 #include "ldo.h"
 #include "llex.h"
 #include "lobject.h"
@@ -29,35 +29,36 @@
 
 
 
-
 #define currIsNewline(ls)	(ls->current == '\n' || ls->current == '\r')
 
 
 /* ORDER RESERVED */
-const char *const luaX_tokens [] = {
+static const char *const luaX_tokens [] = {
     "and", "break", "do", "else", "elseif",
-    "end", "false", "for", "function", "if",
+    "end", "false", "for", "function", "goto", "if",
     "in", "local", "nil", "not", "or", "repeat",
     "return", "then", "true", "until", "while",
-    "..", "...", "==", ">=", "<=", "~=",
-    "<number>", "<name>", "<string>", "<eof>",
-    NULL
+    "..", "...", "==", ">=", "<=", "~=", "::", "<eof>",
+    "<number>", "<name>", "<string>"
 };
 
 
 #define save_and_next(ls) (save(ls, ls->current), next(ls))
 
 
+static void lexerror (LexState *ls, const char *msg, int token);
+
+
 static void save (LexState *ls, int c) {
   Mbuffer *b = ls->buff;
-  if (b->n + 1 > b->buffsize) {
+  if (luaZ_bufflen(b) + 1 > luaZ_sizebuffer(b)) {
     size_t newsize;
-    if (b->buffsize >= MAX_SIZET/2)
-      luaX_lexerror(ls, "lexical element too long", 0);
-    newsize = b->buffsize * 2;
+    if (luaZ_sizebuffer(b) >= MAX_SIZET/2)
+      lexerror(ls, "lexical element too long", 0);
+    newsize = luaZ_sizebuffer(b) * 2;
     luaZ_resizebuffer(ls->L, b, newsize);
   }
-  b->buffer[b->n++] = cast(char, c);
+  b->buffer[luaZ_bufflen(b)++] = cast(char, c);
 }
 
 
@@ -66,23 +67,24 @@ void luaX_init (lua_State *L) {
   for (i=0; i<NUM_RESERVED; i++) {
     TString *ts = luaS_new(L, luaX_tokens[i]);
     luaS_fix(ts);  /* reserved words are never collected */
-    lua_assert(strlen(luaX_tokens[i])+1 <= TOKEN_LEN);
     ts->tsv.reserved = cast_byte(i+1);  /* reserved word */
   }
 }
 
 
-#define MAXSRC          80
-
-
 const char *luaX_token2str (LexState *ls, int token) {
   if (token < FIRST_RESERVED) {
     lua_assert(token == cast(unsigned char, token));
-    return (iscntrl(token)) ? luaO_pushfstring(ls->L, "char(%d)", token) :
-                              luaO_pushfstring(ls->L, "%c", token);
+    return (lisprint(token)) ? luaO_pushfstring(ls->L, LUA_QL("%c"), token) :
+                              luaO_pushfstring(ls->L, "char(%d)", token);
+  }
+  else {
+    const char *s = luaX_tokens[token - FIRST_RESERVED];
+    if (token < TK_EOS)
+      return luaO_pushfstring(ls->L, LUA_QS, s);
+    else
+      return s;
   }
-  else
-    return luaX_tokens[token-FIRST_RESERVED];
 }
 
 
@@ -92,40 +94,52 @@ static const char *txtToken (LexState *ls, int token) {
     case TK_STRING:
     case TK_NUMBER:
       save(ls, '\0');
-      return luaZ_buffer(ls->buff);
+      return luaO_pushfstring(ls->L, LUA_QS, luaZ_buffer(ls->buff));
     default:
       return luaX_token2str(ls, token);
   }
 }
 
 
-void luaX_lexerror (LexState *ls, const char *msg, int token) {
-  char buff[MAXSRC];
-  luaO_chunkid(buff, getstr(ls->source), MAXSRC);
+static void lexerror (LexState *ls, const char *msg, int token) {
+  char buff[LUA_IDSIZE];
+  luaO_chunkid(buff, getstr(ls->source), LUA_IDSIZE);
   msg = luaO_pushfstring(ls->L, "%s:%d: %s", buff, ls->linenumber, msg);
   if (token)
-    luaO_pushfstring(ls->L, "%s near " LUA_QS, msg, txtToken(ls, token));
+    luaO_pushfstring(ls->L, "%s near %s", msg, txtToken(ls, token));
   luaD_throw(ls->L, LUA_ERRSYNTAX);
 }
 
 
 void luaX_syntaxerror (LexState *ls, const char *msg) {
-  luaX_lexerror(ls, msg, ls->t.token);
+  lexerror(ls, msg, ls->t.token);
 }
 
 
+/*
+** creates a new string and anchors it in function's table so that
+** it will not be collected until the end of the function's compilation
+** (by that time it should be anchored in function's prototype)
+*/
 TString *luaX_newstring (LexState *ls, const char *str, size_t l) {
   lua_State *L = ls->L;
-  TString *ts = luaS_newlstr(L, str, l);
-  TValue *o = luaH_setstr(L, ls->fs->h, ts);  /* entry for `str' */
+  TValue *o;  /* entry for `str' */
+  TString *ts = luaS_newlstr(L, str, l);  /* create new string */
+  setsvalue2s(L, L->top++, ts);  /* temporarily anchor it in stack */
+  o = luaH_setstr(L, ls->fs->h, ts);
   if (ttisnil(o)) {
-    setbvalue(o, 1);  /* make sure `str' will not be collected */
+    setbvalue(o, 1);  /* t[string] = true */
     luaC_checkGC(L);
   }
+  L->top--;  /* remove string from stack */
   return ts;
 }
 
 
+/*
+** increment line number and skips newline sequence (any of
+** \n, \r, \n\r, or \r\n)
+*/
 static void inclinenumber (LexState *ls) {
   int old = ls->current;
   lua_assert(currIsNewline(ls));
@@ -137,17 +151,20 @@ static void inclinenumber (LexState *ls) {
 }
 
 
-void luaX_setinput (lua_State *L, LexState *ls, ZIO *z, TString *source) {
+void luaX_setinput (lua_State *L, LexState *ls, ZIO *z, TString *source,
+                    int firstchar) {
   ls->decpoint = '.';
   ls->L = L;
+  ls->current = firstchar;
   ls->lookahead.token = TK_EOS;  /* no look-ahead token */
   ls->z = z;
   ls->fs = NULL;
   ls->linenumber = 1;
   ls->lastline = 1;
   ls->source = source;
+  ls->envn = luaS_new(L, LUA_ENV);  /* create env name */
+  luaS_fix(ls->envn);  /* never collect this name */
   luaZ_resizebuffer(ls->L, ls->buff, LUA_MINBUFFER);  /* initialize buffer */
-  next(ls);  /* read first char */
 }
 
 
@@ -161,13 +178,16 @@ void luaX_setinput (lua_State *L, LexState *ls, ZIO *z, TString *source) {
 
 
 static int check_next (LexState *ls, const char *set) {
-  if (!strchr(set, ls->current))
+  if (ls->current == '\0' || !strchr(set, ls->current))
     return 0;
   save_and_next(ls);
   return 1;
 }
 
 
+/*
+** change all characters 'from' in buffer to 'to'
+*/
 static void buffreplace (LexState *ls, char from, char to) {
   size_t n = luaZ_bufflen(ls->buff);
   char *p = luaZ_buffer(ls->buff);
@@ -176,37 +196,48 @@ static void buffreplace (LexState *ls, char from, char to) {
 }
 
 
+#if !defined(getlocaledecpoint)
+#define getlocaledecpoint()	(localeconv()->decimal_point[0])
+#endif
+
+
+#define buff2d(b,e)	luaO_str2d(luaZ_buffer(b), luaZ_bufflen(b) - 1, e)
+
+/*
+** in case of format error, try to change decimal point separator to
+** the one defined in the current locale and check again
+*/
 static void trydecpoint (LexState *ls, SemInfo *seminfo) {
-  /* format error: try to update decimal point separator */
-  struct lconv *cv = localeconv();
   char old = ls->decpoint;
-  ls->decpoint = (cv ? cv->decimal_point[0] : '.');
-  buffreplace(ls, old, ls->decpoint);  /* try updated decimal separator */
-  if (!luaO_str2d(luaZ_buffer(ls->buff), &seminfo->r)) {
+  ls->decpoint = getlocaledecpoint();
+  buffreplace(ls, old, ls->decpoint);  /* try new decimal separator */
+  if (!buff2d(ls->buff, &seminfo->r)) {
     /* format error with correct decimal point: no more options */
     buffreplace(ls, ls->decpoint, '.');  /* undo change (for error message) */
-    luaX_lexerror(ls, "malformed number", TK_NUMBER);
+    lexerror(ls, "malformed number", TK_NUMBER);
   }
 }
 
 
 /* LUA_NUMBER */
 static void read_numeral (LexState *ls, SemInfo *seminfo) {
-  lua_assert(isdigit(ls->current));
+  lua_assert(lisdigit(ls->current));
   do {
     save_and_next(ls);
-  } while (isdigit(ls->current) || ls->current == '.');
-  if (check_next(ls, "Ee"))  /* `E'? */
-    check_next(ls, "+-");  /* optional exponent sign */
-  while (isalnum(ls->current) || ls->current == '_')
-    save_and_next(ls);
+    if (check_next(ls, "EePp"))  /* exponent part? */
+      check_next(ls, "+-");  /* optional exponent sign */
+  } while (lislalnum(ls->current) || ls->current == '.');
   save(ls, '\0');
   buffreplace(ls, '.', ls->decpoint);  /* follow locale for decimal point */
-  if (!luaO_str2d(luaZ_buffer(ls->buff), &seminfo->r))  /* format error? */
+  if (!buff2d(ls->buff, &seminfo->r))  /* format error? */
     trydecpoint(ls, seminfo); /* try to update decimal point separator */
 }
 
 
+/*
+** skip a sequence '[=*[' or ']=*]' and return its number of '='s or
+** -1 if sequence is malformed
+*/
 static int skip_sep (LexState *ls) {
   int count = 0;
   int s = ls->current;
@@ -221,43 +252,23 @@ static int skip_sep (LexState *ls) {
 
 
 static void read_long_string (LexState *ls, SemInfo *seminfo, int sep) {
-  int cont = 0;
-  (void)(cont);  /* avoid warnings when `cont' is not used */
   save_and_next(ls);  /* skip 2nd `[' */
   if (currIsNewline(ls))  /* string starts with a newline? */
     inclinenumber(ls);  /* skip it */
   for (;;) {
     switch (ls->current) {
       case EOZ:
-        luaX_lexerror(ls, (seminfo) ? "unfinished long string" :
-                                   "unfinished long comment", TK_EOS);
+        lexerror(ls, (seminfo) ? "unfinished long string" :
+                                 "unfinished long comment", TK_EOS);
         break;  /* to avoid warnings */
-#if defined(LUA_COMPAT_LSTR)
-      case '[': {
-        if (skip_sep(ls) == sep) {
-          save_and_next(ls);  /* skip 2nd `[' */
-          cont++;
-#if LUA_COMPAT_LSTR == 1
-          if (sep == 0)
-            luaX_lexerror(ls, "nesting of [[...]] is deprecated", '[');
-#endif
-        }
-        break;
-      }
-#endif
       case ']': {
         if (skip_sep(ls) == sep) {
           save_and_next(ls);  /* skip 2nd `]' */
-#if defined(LUA_COMPAT_LSTR) && LUA_COMPAT_LSTR == 2
-          cont--;
-          if (sep == 0 && cont >= 0) break;
-#endif
           goto endloop;
         }
         break;
       }
-      case '\n':
-      case '\r': {
+      case '\n': case '\r': {
         save(ls, '\n');
         inclinenumber(ls);
         if (!seminfo) luaZ_resetbuffer(ls->buff);  /* avoid wasting space */
@@ -275,19 +286,67 @@ static void read_long_string (LexState *ls, SemInfo *seminfo, int sep) {
 }
 
 
+static void escerror (LexState *ls, int *c, int n, const char *msg) {
+  int i;
+  luaZ_resetbuffer(ls->buff);  /* prepare error message */
+  save(ls, '\\');
+  for (i = 0; i < n && c[i] != EOZ; i++)
+    save(ls, c[i]);
+  lexerror(ls, msg, TK_STRING);
+}
+
+
+static int readhexaesc (LexState *ls) {
+  int c[3];  /* keep input for error message */
+  int i = 2;  /* at least 'x?' will go to error message */
+  c[0] = 'x';
+  c[1] = next(ls);  /* first hexa digit */
+  if (lisxdigit(c[1])) {
+    c[i++] = next(ls);  /* second hexa digit */
+    if (lisxdigit(c[2]))
+      return (luaO_hexavalue(c[1]) << 4) + luaO_hexavalue(c[2]);
+    /* else go through to error */
+  }
+  escerror(ls, c, i, "hexadecimal digit expected");
+  return 0;  /* to avoid warnings */
+}
+
+
+static int readdecesc (LexState *ls) {
+  int c[3], r;
+  int i = 2;  /* at least two chars will be read */
+  c[0] = ls->current;  /* first char must be a digit */
+  c[1] = next(ls);  /* read second char */
+  r = c[0] - '0';  /* partial result */
+  if (lisdigit(c[1])) {
+    c[i++] = next(ls);  /* read third char */
+    r = 10*r + c[1] - '0';  /* update result */
+    if (lisdigit(c[2])) {
+      r = 10*r + c[2] - '0';  /* update result */
+      if (r > UCHAR_MAX)
+        escerror(ls, c, i, "decimal escape too large");
+      return r;
+    }
+  }
+  /* else, has read one character that was not a digit */
+  zungetc(ls->z);  /* return it to input stream */
+  return r;
+}
+
+
 static void read_string (LexState *ls, int del, SemInfo *seminfo) {
-  save_and_next(ls);
+  save_and_next(ls);  /* keep delimiter (for error messages) */
   while (ls->current != del) {
     switch (ls->current) {
       case EOZ:
-        luaX_lexerror(ls, "unfinished string", TK_EOS);
-        continue;  /* to avoid warnings */
+        lexerror(ls, "unfinished string", TK_EOS);
+        break;  /* to avoid warnings */
       case '\n':
       case '\r':
-        luaX_lexerror(ls, "unfinished string", TK_STRING);
-        continue;  /* to avoid warnings */
-      case '\\': {
-        int c;
+        lexerror(ls, "unfinished string", TK_STRING);
+        break;  /* to avoid warnings */
+      case '\\': {  /* escape sequences */
+        int c;  /* final character to be saved */
         next(ls);  /* do not save the `\' */
         switch (ls->current) {
           case 'a': c = '\a'; break;
@@ -297,29 +356,30 @@ static void read_string (LexState *ls, int del, SemInfo *seminfo) {
           case 'r': c = '\r'; break;
           case 't': c = '\t'; break;
           case 'v': c = '\v'; break;
-          case '\n':  /* go through */
+          case 'x': c = readhexaesc(ls); break;
+          case '\n':
           case '\r': save(ls, '\n'); inclinenumber(ls); continue;
+          case '\\': case '\"': case '\'': c = ls->current; break;
           case EOZ: continue;  /* will raise an error next loop */
-          default: {
-            if (!isdigit(ls->current))
-              save_and_next(ls);  /* handles \\, \", \', and \? */
-            else {  /* \xxx */
-              int i = 0;
-              c = 0;
-              do {
-                c = 10*c + (ls->current-'0');
-                next(ls);
-              } while (++i<3 && isdigit(ls->current));
-              if (c > UCHAR_MAX)
-                luaX_lexerror(ls, "escape sequence too large", TK_STRING);
-              save(ls, c);
+          case 'z': {  /* zap following span of spaces */
+            next(ls);  /* skip the 'z' */
+            while (lisspace(ls->current)) {
+              if (currIsNewline(ls)) inclinenumber(ls);
+              else next(ls);
             }
-            continue;
+            continue;  /* do not save 'c' */
+          }
+          default: {
+            if (!lisdigit(ls->current))
+              escerror(ls, &ls->current, 1, "invalid escape sequence");
+            /* digital escape \ddd */
+            c = readdecesc(ls);
+            break;
           }
         }
-        save(ls, c);
         next(ls);
-        continue;
+        save(ls, c);
+        break;
       }
       default:
         save_and_next(ls);
@@ -335,38 +395,41 @@ static int llex (LexState *ls, SemInfo *seminfo) {
   luaZ_resetbuffer(ls->buff);
   for (;;) {
     switch (ls->current) {
-      case '\n':
-      case '\r': {
+      case '\n': case '\r': {  /* line breaks */
         inclinenumber(ls);
-        continue;
+        break;
       }
-      case '-': {
+      case ' ': case '\f': case '\t': case '\v': {  /* spaces */
+        next(ls);
+        break;
+      }
+      case '-': {  /* '-' or '--' (comment) */
         next(ls);
         if (ls->current != '-') return '-';
         /* else is a comment */
         next(ls);
-        if (ls->current == '[') {
+        if (ls->current == '[') {  /* long comment? */
           int sep = skip_sep(ls);
           luaZ_resetbuffer(ls->buff);  /* `skip_sep' may dirty the buffer */
           if (sep >= 0) {
-            read_long_string(ls, NULL, sep);  /* long comment */
-            luaZ_resetbuffer(ls->buff);
-            continue;
+            read_long_string(ls, NULL, sep);  /* skip long comment */
+            luaZ_resetbuffer(ls->buff);  /* previous call may dirty the buff. */
+            break;
           }
         }
         /* else short comment */
         while (!currIsNewline(ls) && ls->current != EOZ)
-          next(ls);
-        continue;
+          next(ls);  /* skip until end of line (or end of file) */
+        break;
       }
-      case '[': {
+      case '[': {  /* long string or simply '[' */
         int sep = skip_sep(ls);
         if (sep >= 0) {
           read_long_string(ls, seminfo, sep);
           return TK_STRING;
         }
         else if (sep == -1) return '[';
-        else luaX_lexerror(ls, "invalid long string delimiter", TK_STRING);
+        else lexerror(ls, "invalid long string delimiter", TK_STRING);
       }
       case '=': {
         next(ls);
@@ -388,56 +451,52 @@ static int llex (LexState *ls, SemInfo *seminfo) {
         if (ls->current != '=') return '~';
         else { next(ls); return TK_NE; }
       }
-      case '"':
-      case '\'': {
+      case ':': {
+        next(ls);
+        if (ls->current != ':') return ':';
+        else { next(ls); return TK_DBCOLON; }
+      }
+      case '"': case '\'': {  /* short literal strings */
         read_string(ls, ls->current, seminfo);
         return TK_STRING;
       }
-      case '.': {
+      case '.': {  /* '.', '..', '...', or number */
         save_and_next(ls);
         if (check_next(ls, ".")) {
           if (check_next(ls, "."))
-            return TK_DOTS;   /* ... */
-          else return TK_CONCAT;   /* .. */
-        }
-        else if (!isdigit(ls->current)) return '.';
-        else {
-          read_numeral(ls, seminfo);
-          return TK_NUMBER;
+            return TK_DOTS;   /* '...' */
+          else return TK_CONCAT;   /* '..' */
         }
+        else if (!lisdigit(ls->current)) return '.';
+        /* else go through */
+      }
+      case '0': case '1': case '2': case '3': case '4':
+      case '5': case '6': case '7': case '8': case '9': {
+        read_numeral(ls, seminfo);
+        return TK_NUMBER;
       }
       case EOZ: {
         return TK_EOS;
       }
       default: {
-        if (isspace(ls->current)) {
-          lua_assert(!currIsNewline(ls));
-          next(ls);
-          continue;
-        }
-        else if (isdigit(ls->current)) {
-          read_numeral(ls, seminfo);
-          return TK_NUMBER;
-        }
-        else if (isalpha(ls->current) || ls->current == '_') {
-          /* identifier or reserved word */
+        if (lislalpha(ls->current)) {  /* identifier or reserved word? */
           TString *ts;
           do {
             save_and_next(ls);
-          } while (isalnum(ls->current) || ls->current == '_');
+          } while (lislalnum(ls->current));
           ts = luaX_newstring(ls, luaZ_buffer(ls->buff),
                                   luaZ_bufflen(ls->buff));
+          seminfo->ts = ts;
           if (ts->tsv.reserved > 0)  /* reserved word? */
             return ts->tsv.reserved - 1 + FIRST_RESERVED;
           else {
-            seminfo->ts = ts;
             return TK_NAME;
           }
         }
-        else {
+        else {  /* single-char tokens (+ - / ...) */
           int c = ls->current;
           next(ls);
-          return c;  /* single-char tokens (+ - / ...) */
+          return c;
         }
       }
     }
@@ -456,8 +515,9 @@ void luaX_next (LexState *ls) {
 }
 
 
-void luaX_lookahead (LexState *ls) {
+int luaX_lookahead (LexState *ls) {
   lua_assert(ls->lookahead.token == TK_EOS);
   ls->lookahead.token = llex(ls, &ls->lookahead.seminfo);
+  return ls->lookahead.token;
 }
 
diff --git a/src/llex.h b/src/llex.h
index a9201ce..ce0bad4 100644..100755
--- a/src/llex.h
+++ b/src/llex.h
@@ -1,5 +1,5 @@
 /*
-** $Id: llex.h,v 1.58.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: llex.h,v 1.71 2011/06/20 16:52:48 roberto Exp $
 ** Lexical Analyzer
 ** See Copyright Notice in lua.h
 */
@@ -13,8 +13,6 @@
 
 #define FIRST_RESERVED	257
 
-/* maximum length of a reserved word */
-#define TOKEN_LEN	(sizeof("function")/sizeof(char))
 
 
 /*
@@ -25,21 +23,17 @@ enum RESERVED {
   /* terminal symbols denoted by reserved words */
   TK_AND = FIRST_RESERVED, TK_BREAK,
   TK_DO, TK_ELSE, TK_ELSEIF, TK_END, TK_FALSE, TK_FOR, TK_FUNCTION,
-  TK_IF, TK_IN, TK_LOCAL, TK_NIL, TK_NOT, TK_OR, TK_REPEAT,
+  TK_GOTO, TK_IF, TK_IN, TK_LOCAL, TK_NIL, TK_NOT, TK_OR, TK_REPEAT,
   TK_RETURN, TK_THEN, TK_TRUE, TK_UNTIL, TK_WHILE,
   /* other terminal symbols */
-  TK_CONCAT, TK_DOTS, TK_EQ, TK_GE, TK_LE, TK_NE, TK_NUMBER,
-  TK_NAME, TK_STRING, TK_EOS
+  TK_CONCAT, TK_DOTS, TK_EQ, TK_GE, TK_LE, TK_NE, TK_DBCOLON, TK_EOS,
+  TK_NUMBER, TK_NAME, TK_STRING
 };
 
 /* number of reserved words */
 #define NUM_RESERVED	(cast(int, TK_WHILE-FIRST_RESERVED+1))
 
 
-/* array with token `names' */
-LUAI_DATA const char *const luaX_tokens [];
-
-
 typedef union {
   lua_Number r;
   TString *ts;
@@ -52,28 +46,31 @@ typedef struct Token {
 } Token;
 
 
+/* state of the lexer plus state of the parser when shared by all
+   functions */
 typedef struct LexState {
   int current;  /* current character (charint) */
   int linenumber;  /* input line counter */
   int lastline;  /* line of last token `consumed' */
   Token t;  /* current token */
   Token lookahead;  /* look ahead token */
-  struct FuncState *fs;  /* `FuncState' is private to the parser */
+  struct FuncState *fs;  /* current function (parser) */
   struct lua_State *L;
   ZIO *z;  /* input stream */
   Mbuffer *buff;  /* buffer for tokens */
+  struct Dyndata *dyd;  /* dynamic structures used by the parser */
   TString *source;  /* current source name */
+  TString *envn;  /* environment variable name */
   char decpoint;  /* locale decimal point */
 } LexState;
 
 
 LUAI_FUNC void luaX_init (lua_State *L);
 LUAI_FUNC void luaX_setinput (lua_State *L, LexState *ls, ZIO *z,
-                              TString *source);
+                              TString *source, int firstchar);
 LUAI_FUNC TString *luaX_newstring (LexState *ls, const char *str, size_t l);
 LUAI_FUNC void luaX_next (LexState *ls);
-LUAI_FUNC void luaX_lookahead (LexState *ls);
-LUAI_FUNC void luaX_lexerror (LexState *ls, const char *msg, int token);
+LUAI_FUNC int luaX_lookahead (LexState *ls);
 LUAI_FUNC void luaX_syntaxerror (LexState *ls, const char *s);
 LUAI_FUNC const char *luaX_token2str (LexState *ls, int token);
 
diff --git a/src/llimits.h b/src/llimits.h
index ca8dcb7..b64c7b7 100644..100755
--- a/src/llimits.h
+++ b/src/llimits.h
@@ -1,5 +1,5 @@
 /*
-** $Id: llimits.h,v 1.69.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: llimits.h,v 1.90 2011/07/02 15:57:25 roberto Exp $
 ** Limits, basic types, and some other `installation-dependent' definitions
 ** See Copyright Notice in lua.h
 */
@@ -15,7 +15,7 @@
 #include "lua.h"
 
 
-typedef LUAI_UINT32 lu_int32;
+typedef unsigned LUA_INT32 lu_int32;
 
 typedef LUAI_UMEM lu_mem;
 
@@ -30,6 +30,7 @@ typedef unsigned char lu_byte;
 #define MAX_SIZET	((size_t)(~(size_t)0)-2)
 
 #define MAX_LUMEM	((lu_mem)(~(lu_mem)0)-2)
+#define MIN_LMEM	((l_mem)~((~(lu_mem)0)>>1))
 
 
 #define MAX_INT (INT_MAX-2)  /* maximum value of an int (-2 for safety) */
@@ -44,6 +45,10 @@ typedef unsigned char lu_byte;
 
 
 /* type to ensure maximum alignment */
+#if !defined(LUAI_USER_ALIGNMENT_T)
+#define LUAI_USER_ALIGNMENT_T	union { double u; void *s; long l; }
+#endif
+
 typedef LUAI_USER_ALIGNMENT_T L_Umaxalign;
 
 
@@ -52,34 +57,60 @@ typedef LUAI_UACNUMBER l_uacNumber;
 
 
 /* internal assertions for in-house debugging */
-#ifdef lua_assert
-
+#if defined(lua_assert)
 #define check_exp(c,e)		(lua_assert(c), (e))
-#define api_check(l,e)		lua_assert(e)
-
+/* to avoid problems with conditions too long */
+#define lua_longassert(c)	{ if (!(c)) lua_assert(0); }
 #else
-
-#define lua_assert(c)		((void)0)
+#define lua_assert(c)		/* empty */
 #define check_exp(c,e)		(e)
-#define api_check		luai_apicheck
+#define lua_longassert(c)	/* empty */
+#endif
 
+/*
+** assertion for checking API calls
+*/
+#if !defined(luai_apicheck)
+
+#if defined(LUA_USE_APICHECK)
+#include <assert.h>
+#define luai_apicheck(L,e)	assert(e)
+#else
+#define luai_apicheck(L,e)	lua_assert(e)
 #endif
 
+#endif
+
+#define api_check(l,e,msg)	luai_apicheck(l,(e) && msg)
+
 
-#ifndef UNUSED
+#if !defined(UNUSED)
 #define UNUSED(x)	((void)(x))	/* to avoid warnings */
 #endif
 
 
-#ifndef cast
 #define cast(t, exp)	((t)(exp))
-#endif
 
 #define cast_byte(i)	cast(lu_byte, (i))
 #define cast_num(i)	cast(lua_Number, (i))
 #define cast_int(i)	cast(int, (i))
+#define cast_uchar(i)	cast(unsigned char, (i))
 
 
+/*
+** maximum depth for nested C calls and syntactical nested non-terminals
+** in a program. (Value must fit in an unsigned short int.)
+*/
+#if !defined(LUAI_MAXCCALLS)
+#define LUAI_MAXCCALLS		200
+#endif
+
+/*
+** maximum number of upvalues in a closure (both C and Lua). (Value
+** must fit in an unsigned char.)
+*/
+#define MAXUPVAL	UCHAR_MAX
+
 
 /*
 ** type for virtual-machine instructions
@@ -95,34 +126,165 @@ typedef lu_int32 Instruction;
 
 
 /* minimum size for the string table (must be power of 2) */
-#ifndef MINSTRTABSIZE
+#if !defined(MINSTRTABSIZE)
 #define MINSTRTABSIZE	32
 #endif
 
 
 /* minimum size for string buffer */
-#ifndef LUA_MINBUFFER
+#if !defined(LUA_MINBUFFER)
 #define LUA_MINBUFFER	32
 #endif
 
 
-#ifndef lua_lock
-#define lua_lock(L)     ((void) 0) 
+#if !defined(lua_lock)
+#define lua_lock(L)     ((void) 0)
 #define lua_unlock(L)   ((void) 0)
 #endif
 
-#ifndef luai_threadyield
+#if !defined(luai_threadyield)
 #define luai_threadyield(L)     {lua_unlock(L); lua_lock(L);}
 #endif
 
 
 /*
+** these macros allow user-specific actions on threads when you defined
+** LUAI_EXTRASPACE and need to do something extra when a thread is
+** created/deleted/resumed/yielded.
+*/
+#if !defined(luai_userstateopen)
+#define luai_userstateopen(L)		((void)L)
+#endif
+
+#if !defined(luai_userstateclose)
+#define luai_userstateclose(L)		((void)L)
+#endif
+
+#if !defined(luai_userstatethread)
+#define luai_userstatethread(L,L1)	((void)L)
+#endif
+
+#if !defined(luai_userstatefree)
+#define luai_userstatefree(L,L1)	((void)L)
+#endif
+
+#if !defined(luai_userstateresume)
+#define luai_userstateresume(L,n)       ((void)L)
+#endif
+
+#if !defined(luai_userstateyield)
+#define luai_userstateyield(L,n)        ((void)L)
+#endif
+
+/*
+** lua_number2int is a macro to convert lua_Number to int.
+** lua_number2integer is a macro to convert lua_Number to lua_Integer.
+** lua_number2unsigned is a macro to convert a lua_Number to a lua_Unsigned.
+** lua_unsigned2number is a macro to convert a lua_Unsigned to a lua_Number.
+** luai_hashnum is a macro to hash a lua_Number value into an integer.
+** The hash must be deterministic and give reasonable values for
+** both small and large values (outside the range of integers).
+*/
+
+#if defined(MS_ASMTRICK)	/* { */
+/* trick with Microsoft assembler for X86 */
+
+#define lua_number2int(i,n)  __asm {__asm fld n   __asm fistp i}
+#define lua_number2integer(i,n)		lua_number2int(i, n)
+#define lua_number2unsigned(i,n)  \
+  {__int64 l; __asm {__asm fld n   __asm fistp l} i = (unsigned int)l;}
+
+
+#elif defined(LUA_IEEE754TRICK)		/* }{ */
+/* the next trick should work on any machine using IEEE754 with
+   a 32-bit integer type */
+
+union luai_Cast { double l_d; LUA_INT32 l_p[2]; };
+
+#if !defined(LUA_IEEEENDIAN)	/* { */
+#define LUAI_EXTRAIEEE	\
+  static const union luai_Cast ieeeendian = {-(33.0 + 6755399441055744.0)};
+#define LUA_IEEEENDIAN		(ieeeendian.l_p[1] == 33)
+#else
+#define LUAI_EXTRAIEEE		/* empty */
+#endif				/* } */
+
+#define lua_number2int32(i,n,t) \
+  { LUAI_EXTRAIEEE \
+    volatile union luai_Cast u; u.l_d = (n) + 6755399441055744.0; \
+    (i) = (t)u.l_p[LUA_IEEEENDIAN]; }
+
+#define luai_hashnum(i,n)  \
+  { volatile union luai_Cast u; u.l_d = (n) + 1.0;  /* avoid -0 */ \
+    (i) = u.l_p[0] + u.l_p[1]; }  /* add double bits for his hash */
+
+#define lua_number2int(i,n)		lua_number2int32(i, n, int)
+#define lua_number2integer(i,n)		lua_number2int32(i, n, lua_Integer)
+#define lua_number2unsigned(i,n)	lua_number2int32(i, n, lua_Unsigned)
+
+#endif				/* } */
+
+
+/* the following definitions always work, but may be slow */
+
+#if !defined(lua_number2int)
+#define lua_number2int(i,n)	((i)=(int)(n))
+#endif
+
+#if !defined(lua_number2integer)
+#define lua_number2integer(i,n)	((i)=(lua_Integer)(n))
+#endif
+
+#if !defined(lua_number2unsigned)	/* { */
+/* the following definition assures proper modulo behavior */
+#if defined(LUA_NUMBER_DOUBLE)
+#include <math.h>
+#define SUPUNSIGNED	((lua_Number)(~(lua_Unsigned)0) + 1)
+#define lua_number2unsigned(i,n)  \
+	((i)=(lua_Unsigned)((n) - floor((n)/SUPUNSIGNED)*SUPUNSIGNED))
+#else
+#define lua_number2unsigned(i,n)	((i)=(lua_Unsigned)(n))
+#endif
+#endif				/* } */
+
+
+#if !defined(lua_unsigned2number)
+/* on several machines, coercion from unsigned to double is slow,
+   so it may be worth to avoid */
+#define lua_unsigned2number(u)  \
+    (((u) <= (lua_Unsigned)INT_MAX) ? (lua_Number)(int)(u) : (lua_Number)(u))
+#endif
+
+
+
+#if (defined(ltable_c) || defined(luaall_c)) && !defined(luai_hashnum)
+
+#include <float.h>
+#include <math.h>
+
+#define luai_hashnum(i,n) { int e;  \
+  n = frexp(n, &e) * (lua_Number)(INT_MAX - DBL_MAX_EXP);  \
+  lua_number2int(i, n); i += e; }
+
+#endif
+
+
+
+/*
 ** macro to control inclusion of some hard tests on stack reallocation
-*/ 
-#ifndef HARDSTACKTESTS
-#define condhardstacktests(x)	((void)0)
+*/
+#if !defined(HARDSTACKTESTS)
+#define condmovestack(L)	((void)0)
+#else
+/* realloc stack keeping its size */
+#define condmovestack(L)	luaD_reallocstack((L), (L)->stacksize)
+#endif
+
+#if !defined(HARDMEMTESTS)
+#define condchangemem(L)	condmovestack(L)
 #else
-#define condhardstacktests(x)	x
+#define condchangemem(L)  \
+	((void)(!(G(L)->gcrunning) || (luaC_fullgc(L, 0), 1)))
 #endif
 
 #endif
diff --git a/src/lmathlib.c b/src/lmathlib.c
index 441fbf7..b17237f 100644..100755
--- a/src/lmathlib.c
+++ b/src/lmathlib.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lmathlib.c,v 1.67.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lmathlib.c,v 1.80 2011/07/05 12:49:35 roberto Exp $
 ** Standard mathematical library
 ** See Copyright Notice in lua.h
 */
@@ -22,107 +22,127 @@
 #define RADIANS_PER_DEGREE (PI/180.0)
 
 
+/* macro 'l_tg' allows the addition of an 'l' or 'f' to all math operations */
+#if !defined(l_tg)
+#define l_tg(x)		(x)
+#endif
+
+
 
 static int math_abs (lua_State *L) {
-  lua_pushnumber(L, fabs(luaL_checknumber(L, 1)));
+  lua_pushnumber(L, l_tg(fabs)(luaL_checknumber(L, 1)));
   return 1;
 }
 
 static int math_sin (lua_State *L) {
-  lua_pushnumber(L, sin(luaL_checknumber(L, 1)));
+  lua_pushnumber(L, l_tg(sin)(luaL_checknumber(L, 1)));
   return 1;
 }
 
 static int math_sinh (lua_State *L) {
-  lua_pushnumber(L, sinh(luaL_checknumber(L, 1)));
+  lua_pushnumber(L, l_tg(sinh)(luaL_checknumber(L, 1)));
   return 1;
 }
 
 static int math_cos (lua_State *L) {
-  lua_pushnumber(L, cos(luaL_checknumber(L, 1)));
+  lua_pushnumber(L, l_tg(cos)(luaL_checknumber(L, 1)));
   return 1;
 }
 
 static int math_cosh (lua_State *L) {
-  lua_pushnumber(L, cosh(luaL_checknumber(L, 1)));
+  lua_pushnumber(L, l_tg(cosh)(luaL_checknumber(L, 1)));
   return 1;
 }
 
 static int math_tan (lua_State *L) {
-  lua_pushnumber(L, tan(luaL_checknumber(L, 1)));
+  lua_pushnumber(L, l_tg(tan)(luaL_checknumber(L, 1)));
   return 1;
 }
 
 static int math_tanh (lua_State *L) {
-  lua_pushnumber(L, tanh(luaL_checknumber(L, 1)));
+  lua_pushnumber(L, l_tg(tanh)(luaL_checknumber(L, 1)));
   return 1;
 }
 
 static int math_asin (lua_State *L) {
-  lua_pushnumber(L, asin(luaL_checknumber(L, 1)));
+  lua_pushnumber(L, l_tg(asin)(luaL_checknumber(L, 1)));
   return 1;
 }
 
 static int math_acos (lua_State *L) {
-  lua_pushnumber(L, acos(luaL_checknumber(L, 1)));
+  lua_pushnumber(L, l_tg(acos)(luaL_checknumber(L, 1)));
   return 1;
 }
 
 static int math_atan (lua_State *L) {
-  lua_pushnumber(L, atan(luaL_checknumber(L, 1)));
+  lua_pushnumber(L, l_tg(atan)(luaL_checknumber(L, 1)));
   return 1;
 }
 
 static int math_atan2 (lua_State *L) {
-  lua_pushnumber(L, atan2(luaL_checknumber(L, 1), luaL_checknumber(L, 2)));
+  lua_pushnumber(L, l_tg(atan2)(luaL_checknumber(L, 1),
+                                luaL_checknumber(L, 2)));
   return 1;
 }
 
 static int math_ceil (lua_State *L) {
-  lua_pushnumber(L, ceil(luaL_checknumber(L, 1)));
+  lua_pushnumber(L, l_tg(ceil)(luaL_checknumber(L, 1)));
   return 1;
 }
 
 static int math_floor (lua_State *L) {
-  lua_pushnumber(L, floor(luaL_checknumber(L, 1)));
+  lua_pushnumber(L, l_tg(floor)(luaL_checknumber(L, 1)));
   return 1;
 }
 
 static int math_fmod (lua_State *L) {
-  lua_pushnumber(L, fmod(luaL_checknumber(L, 1), luaL_checknumber(L, 2)));
+  lua_pushnumber(L, l_tg(fmod)(luaL_checknumber(L, 1),
+                               luaL_checknumber(L, 2)));
   return 1;
 }
 
 static int math_modf (lua_State *L) {
-  double ip;
-  double fp = modf(luaL_checknumber(L, 1), &ip);
+  lua_Number ip;
+  lua_Number fp = l_tg(modf)(luaL_checknumber(L, 1), &ip);
   lua_pushnumber(L, ip);
   lua_pushnumber(L, fp);
   return 2;
 }
 
 static int math_sqrt (lua_State *L) {
-  lua_pushnumber(L, sqrt(luaL_checknumber(L, 1)));
+  lua_pushnumber(L, l_tg(sqrt)(luaL_checknumber(L, 1)));
   return 1;
 }
 
 static int math_pow (lua_State *L) {
-  lua_pushnumber(L, pow(luaL_checknumber(L, 1), luaL_checknumber(L, 2)));
+  lua_pushnumber(L, l_tg(pow)(luaL_checknumber(L, 1),
+                              luaL_checknumber(L, 2)));
   return 1;
 }
 
 static int math_log (lua_State *L) {
-  lua_pushnumber(L, log(luaL_checknumber(L, 1)));
+  lua_Number x = luaL_checknumber(L, 1);
+  lua_Number res;
+  if (lua_isnoneornil(L, 2))
+    res = l_tg(log)(x);
+  else {
+    lua_Number base = luaL_checknumber(L, 2);
+    if (base == 10.0) res = l_tg(log10)(x);
+    else res = l_tg(log)(x)/l_tg(log)(base);
+  }
+  lua_pushnumber(L, res);
   return 1;
 }
 
+#if defined(LUA_COMPAT_LOG10)
 static int math_log10 (lua_State *L) {
-  lua_pushnumber(L, log10(luaL_checknumber(L, 1)));
+  lua_pushnumber(L, l_tg(log10)(luaL_checknumber(L, 1)));
   return 1;
 }
+#endif
 
 static int math_exp (lua_State *L) {
-  lua_pushnumber(L, exp(luaL_checknumber(L, 1)));
+  lua_pushnumber(L, l_tg(exp)(luaL_checknumber(L, 1)));
   return 1;
 }
 
@@ -138,13 +158,14 @@ static int math_rad (lua_State *L) {
 
 static int math_frexp (lua_State *L) {
   int e;
-  lua_pushnumber(L, frexp(luaL_checknumber(L, 1), &e));
+  lua_pushnumber(L, l_tg(frexp)(luaL_checknumber(L, 1), &e));
   lua_pushinteger(L, e);
   return 2;
 }
 
 static int math_ldexp (lua_State *L) {
-  lua_pushnumber(L, ldexp(luaL_checknumber(L, 1), luaL_checkint(L, 2)));
+  lua_pushnumber(L, l_tg(ldexp)(luaL_checknumber(L, 1),
+                                luaL_checkint(L, 2)));
   return 1;
 }
 
@@ -188,16 +209,16 @@ static int math_random (lua_State *L) {
       break;
     }
     case 1: {  /* only upper limit */
-      int u = luaL_checkint(L, 1);
-      luaL_argcheck(L, 1<=u, 1, "interval is empty");
-      lua_pushnumber(L, floor(r*u)+1);  /* int between 1 and `u' */
+      lua_Number u = luaL_checknumber(L, 1);
+      luaL_argcheck(L, 1.0 <= u, 1, "interval is empty");
+      lua_pushnumber(L, l_tg(floor)(r*u) + 1.0);  /* int in [1, u] */
       break;
     }
     case 2: {  /* lower and upper limits */
-      int l = luaL_checkint(L, 1);
-      int u = luaL_checkint(L, 2);
-      luaL_argcheck(L, l<=u, 2, "interval is empty");
-      lua_pushnumber(L, floor(r*(u-l+1))+l);  /* int between `l' and `u' */
+      lua_Number l = luaL_checknumber(L, 1);
+      lua_Number u = luaL_checknumber(L, 2);
+      luaL_argcheck(L, l <= u, 2, "interval is empty");
+      lua_pushnumber(L, l_tg(floor)(r*(u-l+1)) + l);  /* int in [l, u] */
       break;
     }
     default: return luaL_error(L, "wrong number of arguments");
@@ -207,7 +228,8 @@ static int math_random (lua_State *L) {
 
 
 static int math_randomseed (lua_State *L) {
-  srand(luaL_checkint(L, 1));
+  srand(luaL_checkunsigned(L, 1));
+  (void)rand(); /* discard first value to avoid undesirable correlations */
   return 0;
 }
 
@@ -227,7 +249,9 @@ static const luaL_Reg mathlib[] = {
   {"fmod",   math_fmod},
   {"frexp", math_frexp},
   {"ldexp", math_ldexp},
+#if defined(LUA_COMPAT_LOG10)
   {"log10", math_log10},
+#endif
   {"log",   math_log},
   {"max",   math_max},
   {"min",   math_min},
@@ -248,16 +272,12 @@ static const luaL_Reg mathlib[] = {
 /*
 ** Open math library
 */
-LUALIB_API int luaopen_math (lua_State *L) {
-  luaL_register(L, LUA_MATHLIBNAME, mathlib);
+LUAMOD_API int luaopen_math (lua_State *L) {
+  luaL_newlib(L, mathlib);
   lua_pushnumber(L, PI);
   lua_setfield(L, -2, "pi");
   lua_pushnumber(L, HUGE_VAL);
   lua_setfield(L, -2, "huge");
-#if defined(LUA_COMPAT_MOD)
-  lua_getfield(L, -1, "fmod");
-  lua_setfield(L, -2, "mod");
-#endif
   return 1;
 }
 
diff --git a/src/lmem.c b/src/lmem.c
index ae7d8c9..c3775df 100644..100755
--- a/src/lmem.c
+++ b/src/lmem.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lmem.c,v 1.70.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lmem.c,v 1.81 2010/12/20 19:40:07 roberto Exp $
 ** Interface to Memory Manager
 ** See Copyright Notice in lua.h
 */
@@ -14,6 +14,7 @@
 
 #include "ldebug.h"
 #include "ldo.h"
+#include "lgc.h"
 #include "lmem.h"
 #include "lobject.h"
 #include "lstate.h"
@@ -25,12 +26,11 @@
 ** void * frealloc (void *ud, void *ptr, size_t osize, size_t nsize);
 ** (`osize' is the old size, `nsize' is the new size)
 **
-** Lua ensures that (ptr == NULL) iff (osize == 0).
-**
-** * frealloc(ud, NULL, 0, x) creates a new block of size `x'
+** * frealloc(ud, NULL, x, s) creates a new block of size `s' (no
+** matter 'x').
 **
 ** * frealloc(ud, p, x, 0) frees the block `p'
-** (in this specific case, frealloc must return NULL).
+** (in this specific case, frealloc must return NULL);
 ** particularly, frealloc(ud, NULL, 0, 0) does nothing
 ** (which is equivalent to free(NULL) in ANSI C)
 **
@@ -44,12 +44,12 @@
 
 
 void *luaM_growaux_ (lua_State *L, void *block, int *size, size_t size_elems,
-                     int limit, const char *errormsg) {
+                     int limit, const char *what) {
   void *newblock;
   int newsize;
   if (*size >= limit/2) {  /* cannot double it? */
     if (*size >= limit)  /* cannot grow even a little? */
-      luaG_runerror(L, errormsg);
+      luaG_runerror(L, "too many %s (limit is %d)", what, limit);
     newsize = limit;  /* still have at least one free place */
   }
   else {
@@ -74,13 +74,43 @@ void *luaM_toobig (lua_State *L) {
 ** generic allocation routine.
 */
 void *luaM_realloc_ (lua_State *L, void *block, size_t osize, size_t nsize) {
+  void *newblock;
   global_State *g = G(L);
-  lua_assert((osize == 0) == (block == NULL));
-  block = (*g->frealloc)(g->ud, block, osize, nsize);
-  if (block == NULL && nsize > 0)
-    luaD_throw(L, LUA_ERRMEM);
-  lua_assert((nsize == 0) == (block == NULL));
-  g->totalbytes = (g->totalbytes - osize) + nsize;
-  return block;
+  size_t realosize = (block) ? osize : 0;
+  lua_assert((realosize == 0) == (block == NULL));
+#if defined(HARDMEMTESTS)
+  if (nsize > realosize && g->gcrunning)
+    luaC_fullgc(L, 1);  /* force a GC whenever possible */
+#endif
+  newblock = (*g->frealloc)(g->ud, block, osize, nsize);
+  if (newblock == NULL && nsize > 0) {
+    api_check(L, nsize > realosize,
+                 "realloc cannot fail when shrinking a block");
+    if (g->gcrunning) {
+      luaC_fullgc(L, 1);  /* try to free some memory... */
+      newblock = (*g->frealloc)(g->ud, block, osize, nsize);  /* try again */
+    }
+    if (newblock == NULL)
+      luaD_throw(L, LUA_ERRMEM);
+  }
+  lua_assert((nsize == 0) == (newblock == NULL));
+  g->GCdebt = (g->GCdebt + nsize) - realosize;
+#if defined(TRACEMEM)
+  { /* auxiliary patch to monitor garbage collection.
+    ** To plot, gnuplot with following command:
+    ** plot TRACEMEM using 1:2 with lines, TRACEMEM using 1:3 with lines
+    */
+    static unsigned long total = 0;  /* our "time" */
+    static FILE *f = NULL;  /* output file */
+    total++;  /* "time" always grows */
+    if ((total % 200) == 0) {
+      if (f == NULL) f = fopen(TRACEMEM, "w");
+      fprintf(f, "%lu %u %d %d\n", total,
+              g->totalbytes, g->GCdebt, g->gcstate * 1000);
+    }
+  }
+#endif
+
+  return newblock;
 }
 
diff --git a/src/lmem.h b/src/lmem.h
index 7c2dcb3..ff324f8 100644..100755
--- a/src/lmem.h
+++ b/src/lmem.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lmem.h,v 1.31.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lmem.h,v 1.36 2010/04/08 17:16:46 roberto Exp $
 ** Interface to Memory Manager
 ** See Copyright Notice in lua.h
 */
@@ -13,8 +13,6 @@
 #include "llimits.h"
 #include "lua.h"
 
-#define MEMERRMSG	"not enough memory"
-
 
 #define luaM_reallocv(L,b,on,n,e) \
 	((cast(size_t, (n)+1) <= MAX_SIZET/(e)) ?  /* +1 to avoid warnings */ \
@@ -23,13 +21,15 @@
 
 #define luaM_freemem(L, b, s)	luaM_realloc_(L, (b), (s), 0)
 #define luaM_free(L, b)		luaM_realloc_(L, (b), sizeof(*(b)), 0)
-#define luaM_freearray(L, b, n, t)   luaM_reallocv(L, (b), n, 0, sizeof(t))
+#define luaM_freearray(L, b, n)   luaM_reallocv(L, (b), n, 0, sizeof((b)[0]))
 
-#define luaM_malloc(L,t)	luaM_realloc_(L, NULL, 0, (t))
+#define luaM_malloc(L,s)	luaM_realloc_(L, NULL, 0, (s))
 #define luaM_new(L,t)		cast(t *, luaM_malloc(L, sizeof(t)))
 #define luaM_newvector(L,n,t) \
 		cast(t *, luaM_reallocv(L, NULL, 0, n, sizeof(t)))
 
+#define luaM_newobject(L,tag,s)	luaM_realloc_(L, NULL, tag, (s))
+
 #define luaM_growvector(L,v,nelems,size,t,limit,e) \
           if ((nelems)+1 > (size)) \
             ((v)=cast(t *, luaM_growaux_(L,v,&(size),sizeof(t),limit,e)))
@@ -37,13 +37,14 @@
 #define luaM_reallocvector(L, v,oldn,n,t) \
    ((v)=cast(t *, luaM_reallocv(L, v, oldn, n, sizeof(t))))
 
+LUAI_FUNC void *luaM_toobig (lua_State *L);
 
+/* not to be called directly */
 LUAI_FUNC void *luaM_realloc_ (lua_State *L, void *block, size_t oldsize,
                                                           size_t size);
-LUAI_FUNC void *luaM_toobig (lua_State *L);
 LUAI_FUNC void *luaM_growaux_ (lua_State *L, void *block, int *size,
                                size_t size_elem, int limit,
-                               const char *errormsg);
+                               const char *what);
 
 #endif
 
diff --git a/src/loadlib.c b/src/loadlib.c
index 6158c53..0313d8e 100644..100755
--- a/src/loadlib.c
+++ b/src/loadlib.c
@@ -1,11 +1,11 @@
 /*
-** $Id: loadlib.c,v 1.52.1.4 2009/09/09 13:17:16 roberto Exp $
+** $Id: loadlib.c,v 1.100 2011/07/05 12:49:35 roberto Exp $
 ** Dynamic library loader for Lua
 ** See Copyright Notice in lua.h
 **
 ** This module contains an implementation of loadlib for Unix systems
-** that have dlfcn, an implementation for Darwin (Mac OS X), an
-** implementation for Windows, and a stub for other systems.
+** that have dlfcn, an implementation for Windows, and a stub for other
+** systems.
 */
 
 
@@ -22,6 +22,47 @@
 #include "lualib.h"
 
 
+/*
+** LUA_PATH and LUA_CPATH are the names of the environment
+** variables that Lua check to set its paths.
+*/
+#if !defined(LUA_PATH)
+#define LUA_PATH	"LUA_PATH"
+#endif
+
+#if !defined(LUA_CPATH)
+#define LUA_CPATH	"LUA_CPATH"
+#endif
+
+#define LUA_PATHSUFFIX		"_" LUA_VERSION_MAJOR "_" LUA_VERSION_MINOR
+
+#define LUA_PATHVERSION		LUA_PATH LUA_PATHSUFFIX
+#define LUA_CPATHVERSION	LUA_CPATH LUA_PATHSUFFIX
+
+/*
+** LUA_PATH_SEP is the character that separates templates in a path.
+** LUA_PATH_MARK is the string that marks the substitution points in a
+** template.
+** LUA_EXEC_DIR in a Windows path is replaced by the executable's
+** directory.
+** LUA_IGMARK is a mark to ignore all before it when building the
+** luaopen_ function name.
+*/
+#if !defined (LUA_PATH_SEP)
+#define LUA_PATH_SEP		";"
+#endif
+#if !defined (LUA_PATH_MARK)
+#define LUA_PATH_MARK		"?"
+#endif
+#if !defined (LUA_EXEC_DIR)
+#define LUA_EXEC_DIR		"!"
+#endif
+#if !defined (LUA_IGMARK)
+#define LUA_IGMARK		"-"
+#endif
+
+
+
 /* prefix for open functions in C libraries */
 #define LUA_POF		"luaopen_"
 
@@ -42,13 +83,16 @@
 #define setprogdir(L)		((void)0)
 
 
+/*
+** system-dependent functions
+*/
 static void ll_unloadlib (void *lib);
-static void *ll_load (lua_State *L, const char *path);
+static void *ll_load (lua_State *L, const char *path, int seeglb);
 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym);
 
 
 
-#if defined(LUA_DL_DLOPEN)
+#if defined(LUA_USE_DLOPEN)
 /*
 ** {========================================================================
 ** This is an implementation of loadlib based on the dlfcn interface.
@@ -65,8 +109,8 @@ static void ll_unloadlib (void *lib) {
 }
 
 
-static void *ll_load (lua_State *L, const char *path) {
-  void *lib = dlopen(path, RTLD_NOW);
+static void *ll_load (lua_State *L, const char *path, int seeglb) {
+  void *lib = dlopen(path, RTLD_NOW | (seeglb ? RTLD_GLOBAL : 0));
   if (lib == NULL) lua_pushstring(L, dlerror());
   return lib;
 }
@@ -91,9 +135,16 @@ static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
 
 #include <windows.h>
 
-
 #undef setprogdir
 
+/*
+** optional flags for LoadLibraryEx
+*/
+#if !defined(LUA_LLE_FLAGS)
+#define LUA_LLE_FLAGS	0
+#endif
+
+
 static void setprogdir (lua_State *L) {
   char buff[MAX_PATH + 1];
   char *lb;
@@ -103,7 +154,7 @@ static void setprogdir (lua_State *L) {
     luaL_error(L, "unable to get ModuleFileName");
   else {
     *lb = '\0';
-    luaL_gsub(L, lua_tostring(L, -1), LUA_EXECDIR, buff);
+    luaL_gsub(L, lua_tostring(L, -1), LUA_EXEC_DIR, buff);
     lua_remove(L, -2);  /* remove original string */
   }
 }
@@ -113,26 +164,27 @@ static void pusherror (lua_State *L) {
   int error = GetLastError();
   char buffer[128];
   if (FormatMessageA(FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_FROM_SYSTEM,
-      NULL, error, 0, buffer, sizeof(buffer), NULL))
+      NULL, error, 0, buffer, sizeof(buffer)/sizeof(char), NULL))
     lua_pushstring(L, buffer);
   else
     lua_pushfstring(L, "system error %d\n", error);
 }
 
 static void ll_unloadlib (void *lib) {
-  FreeLibrary((HINSTANCE)lib);
+  FreeLibrary((HMODULE)lib);
 }
 
 
-static void *ll_load (lua_State *L, const char *path) {
-  HINSTANCE lib = LoadLibraryA(path);
+static void *ll_load (lua_State *L, const char *path, int seeglb) {
+  HMODULE lib = LoadLibraryExA(path, NULL, LUA_LLE_FLAGS);
+  (void)(seeglb);  /* symbols are 'global' by default */
   if (lib == NULL) pusherror(L);
   return lib;
 }
 
 
 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
-  lua_CFunction f = (lua_CFunction)GetProcAddress((HINSTANCE)lib, sym);
+  lua_CFunction f = (lua_CFunction)GetProcAddress((HMODULE)lib, sym);
   if (f == NULL) pusherror(L);
   return f;
 }
@@ -140,88 +192,6 @@ static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
 /* }====================================================== */
 
 
-
-#elif defined(LUA_DL_DYLD)
-/*
-** {======================================================================
-** Native Mac OS X / Darwin Implementation
-** =======================================================================
-*/
-
-#include <mach-o/dyld.h>
-
-
-/* Mac appends a `_' before C function names */
-#undef POF
-#define POF	"_" LUA_POF
-
-
-static void pusherror (lua_State *L) {
-  const char *err_str;
-  const char *err_file;
-  NSLinkEditErrors err;
-  int err_num;
-  NSLinkEditError(&err, &err_num, &err_file, &err_str);
-  lua_pushstring(L, err_str);
-}
-
-
-static const char *errorfromcode (NSObjectFileImageReturnCode ret) {
-  switch (ret) {
-    case NSObjectFileImageInappropriateFile:
-      return "file is not a bundle";
-    case NSObjectFileImageArch:
-      return "library is for wrong CPU type";
-    case NSObjectFileImageFormat:
-      return "bad format";
-    case NSObjectFileImageAccess:
-      return "cannot access file";
-    case NSObjectFileImageFailure:
-    default:
-      return "unable to load library";
-  }
-}
-
-
-static void ll_unloadlib (void *lib) {
-  NSUnLinkModule((NSModule)lib, NSUNLINKMODULE_OPTION_RESET_LAZY_REFERENCES);
-}
-
-
-static void *ll_load (lua_State *L, const char *path) {
-  NSObjectFileImage img;
-  NSObjectFileImageReturnCode ret;
-  /* this would be a rare case, but prevents crashing if it happens */
-  if(!_dyld_present()) {
-    lua_pushliteral(L, "dyld not present");
-    return NULL;
-  }
-  ret = NSCreateObjectFileImageFromFile(path, &img);
-  if (ret == NSObjectFileImageSuccess) {
-    NSModule mod = NSLinkModule(img, path, NSLINKMODULE_OPTION_PRIVATE |
-                       NSLINKMODULE_OPTION_RETURN_ON_ERROR);
-    NSDestroyObjectFileImage(img);
-    if (mod == NULL) pusherror(L);
-    return mod;
-  }
-  lua_pushstring(L, errorfromcode(ret));
-  return NULL;
-}
-
-
-static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
-  NSSymbol nss = NSLookupSymbolInModule((NSModule)lib, sym);
-  if (nss == NULL) {
-    lua_pushfstring(L, "symbol " LUA_QS " not found", sym);
-    return NULL;
-  }
-  return (lua_CFunction)NSAddressOfSymbol(nss);
-}
-
-/* }====================================================== */
-
-
-
 #else
 /*
 ** {======================================================
@@ -237,19 +207,19 @@ static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
 
 
 static void ll_unloadlib (void *lib) {
-  (void)lib;  /* to avoid warnings */
+  (void)(lib);  /* to avoid warnings */
 }
 
 
-static void *ll_load (lua_State *L, const char *path) {
-  (void)path;  /* to avoid warnings */
+static void *ll_load (lua_State *L, const char *path, int seeglb) {
+  (void)(path); (void)(seeglb);  /* to avoid warnings */
   lua_pushliteral(L, DLMSG);
   return NULL;
 }
 
 
 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
-  (void)lib; (void)sym;  /* to avoid warnings */
+  (void)(lib); (void)(sym);  /* to avoid warnings */
   lua_pushliteral(L, DLMSG);
   return NULL;
 }
@@ -266,11 +236,10 @@ static void **ll_register (lua_State *L, const char *path) {
   if (!lua_isnil(L, -1))  /* is there an entry? */
     plib = (void **)lua_touserdata(L, -1);
   else {  /* no entry yet; create one */
-    lua_pop(L, 1);
+    lua_pop(L, 1);  /* remove result from gettable */
     plib = (void **)lua_newuserdata(L, sizeof(const void *));
     *plib = NULL;
-    luaL_getmetatable(L, "_LOADLIB");
-    lua_setmetatable(L, -2);
+    luaL_setmetatable(L, "_LOADLIB");
     lua_pushfstring(L, "%s%s", LIBPREFIX, path);
     lua_pushvalue(L, -2);
     lua_settable(L, LUA_REGISTRYINDEX);
@@ -293,15 +262,18 @@ static int gctm (lua_State *L) {
 
 static int ll_loadfunc (lua_State *L, const char *path, const char *sym) {
   void **reg = ll_register(L, path);
-  if (*reg == NULL) *reg = ll_load(L, path);
-  if (*reg == NULL)
-    return ERRLIB;  /* unable to load library */
+  if (*reg == NULL) *reg = ll_load(L, path, *sym == '*');
+  if (*reg == NULL) return ERRLIB;  /* unable to load library */
+  if (*sym == '*') {  /* loading only library (no function)? */
+    lua_pushboolean(L, 1);  /* return 'true' */
+    return 0;  /* no errors */
+  }
   else {
     lua_CFunction f = ll_sym(L, *reg, sym);
     if (f == NULL)
       return ERRFUNC;  /* unable to find function */
-    lua_pushcfunction(L, f);
-    return 0;  /* return function */
+    lua_pushcfunction(L, f);  /* else create new function */
+    return 0;  /* no errors */
   }
 }
 
@@ -339,27 +311,24 @@ static int readable (const char *filename) {
 
 static const char *pushnexttemplate (lua_State *L, const char *path) {
   const char *l;
-  while (*path == *LUA_PATHSEP) path++;  /* skip separators */
+  while (*path == *LUA_PATH_SEP) path++;  /* skip separators */
   if (*path == '\0') return NULL;  /* no more templates */
-  l = strchr(path, *LUA_PATHSEP);  /* find next separator */
+  l = strchr(path, *LUA_PATH_SEP);  /* find next separator */
   if (l == NULL) l = path + strlen(path);
   lua_pushlstring(L, path, l - path);  /* template */
   return l;
 }
 
 
-static const char *findfile (lua_State *L, const char *name,
-                                           const char *pname) {
-  const char *path;
-  name = luaL_gsub(L, name, ".", LUA_DIRSEP);
-  lua_getfield(L, LUA_ENVIRONINDEX, pname);
-  path = lua_tostring(L, -1);
-  if (path == NULL)
-    luaL_error(L, LUA_QL("package.%s") " must be a string", pname);
+static const char *searchpath (lua_State *L, const char *name,
+                                             const char *path,
+                                             const char *sep) {
+  if (*sep != '\0')  /* non-empty separator? */
+    name = luaL_gsub(L, name, sep, LUA_DIRSEP);  /* replace it by proper one */
   lua_pushliteral(L, "");  /* error accumulator */
   while ((path = pushnexttemplate(L, path)) != NULL) {
-    const char *filename;
-    filename = luaL_gsub(L, lua_tostring(L, -1), LUA_PATH_MARK, name);
+    const char *filename = luaL_gsub(L, lua_tostring(L, -1),
+                                     LUA_PATH_MARK, name);
     lua_remove(L, -2);  /* remove path template */
     if (readable(filename))  /* does file exist and is readable? */
       return filename;  /* return that file name */
@@ -371,48 +340,78 @@ static const char *findfile (lua_State *L, const char *name,
 }
 
 
-static void loaderror (lua_State *L, const char *filename) {
-  luaL_error(L, "error loading module " LUA_QS " from file " LUA_QS ":\n\t%s",
-                lua_tostring(L, 1), filename, lua_tostring(L, -1));
+static int ll_searchpath (lua_State *L) {
+  const char *f = searchpath(L, luaL_checkstring(L, 1),
+                                luaL_checkstring(L, 2),
+                                luaL_optstring(L, 3, "."));
+  if (f != NULL) return 1;
+  else {  /* error message is on top of the stack */
+    lua_pushnil(L);
+    lua_insert(L, -2);
+    return 2;  /* return nil + error message */
+  }
 }
 
 
-static int loader_Lua (lua_State *L) {
+static const char *findfile (lua_State *L, const char *name,
+                                           const char *pname) {
+  const char *path;
+  lua_getfield(L, lua_upvalueindex(1), pname);
+  path = lua_tostring(L, -1);
+  if (path == NULL)
+    luaL_error(L, LUA_QL("package.%s") " must be a string", pname);
+  return searchpath(L, name, path, ".");
+}
+
+
+static int checkload (lua_State *L, int stat, const char *filename) {
+  if (stat) {  /* module loaded successfully? */
+    lua_pushstring(L, filename);  /* will be 2nd argument to module */
+    return 2;  /* return open function and file name */
+  }
+  else
+    return luaL_error(L, "error loading module " LUA_QS
+                         " from file " LUA_QS ":\n\t%s",
+                          lua_tostring(L, 1), filename, lua_tostring(L, -1));
+}
+
+
+static int searcher_Lua (lua_State *L) {
   const char *filename;
   const char *name = luaL_checkstring(L, 1);
   filename = findfile(L, name, "path");
-  if (filename == NULL) return 1;  /* library not found in this path */
-  if (luaL_loadfile(L, filename) != 0)
-    loaderror(L, filename);
-  return 1;  /* library loaded successfully */
+  if (filename == NULL) return 1;  /* module not found in this path */
+  return checkload(L, (luaL_loadfile(L, filename) == LUA_OK), filename);
 }
 
 
-static const char *mkfuncname (lua_State *L, const char *modname) {
+static int loadfunc (lua_State *L, const char *filename, const char *modname) {
   const char *funcname;
-  const char *mark = strchr(modname, *LUA_IGMARK);
-  if (mark) modname = mark + 1;
-  funcname = luaL_gsub(L, modname, ".", LUA_OFSEP);
-  funcname = lua_pushfstring(L, POF"%s", funcname);
-  lua_remove(L, -2);  /* remove 'gsub' result */
-  return funcname;
+  const char *mark;
+  modname = luaL_gsub(L, modname, ".", LUA_OFSEP);
+  mark = strchr(modname, *LUA_IGMARK);
+  if (mark) {
+    int stat;
+    funcname = lua_pushlstring(L, modname, mark - modname);
+    funcname = lua_pushfstring(L, POF"%s", funcname);
+    stat = ll_loadfunc(L, filename, funcname);
+    if (stat != ERRFUNC) return stat;
+    modname = mark + 1;  /* else go ahead and try old-style name */
+  }
+  funcname = lua_pushfstring(L, POF"%s", modname);
+  return ll_loadfunc(L, filename, funcname);
 }
 
 
-static int loader_C (lua_State *L) {
-  const char *funcname;
+static int searcher_C (lua_State *L) {
   const char *name = luaL_checkstring(L, 1);
   const char *filename = findfile(L, name, "cpath");
-  if (filename == NULL) return 1;  /* library not found in this path */
-  funcname = mkfuncname(L, name);
-  if (ll_loadfunc(L, filename, funcname) != 0)
-    loaderror(L, filename);
-  return 1;  /* library loaded successfully */
+  if (filename == NULL) return 1;  /* module not found in this path */
+  return checkload(L, (loadfunc(L, filename, name) == 0), filename);
 }
 
 
-static int loader_Croot (lua_State *L) {
-  const char *funcname;
+static int searcher_Croot (lua_State *L) {
   const char *filename;
   const char *name = luaL_checkstring(L, 1);
   const char *p = strchr(name, '.');
@@ -421,22 +420,23 @@ static int loader_Croot (lua_State *L) {
   lua_pushlstring(L, name, p - name);
   filename = findfile(L, lua_tostring(L, -1), "cpath");
   if (filename == NULL) return 1;  /* root not found */
-  funcname = mkfuncname(L, name);
-  if ((stat = ll_loadfunc(L, filename, funcname)) != 0) {
-    if (stat != ERRFUNC) loaderror(L, filename);  /* real error */
-    lua_pushfstring(L, "\n\tno module " LUA_QS " in file " LUA_QS,
-                       name, filename);
-    return 1;  /* function not found */
+  if ((stat = loadfunc(L, filename, name)) != 0) {
+    if (stat != ERRFUNC)
+      return checkload(L, 0, filename);  /* real error */
+    else {  /* open function not found */
+      lua_pushfstring(L, "\n\tno module " LUA_QS " in file " LUA_QS,
+                         name, filename);
+      return 1;
+    }
   }
-  return 1;
+  lua_pushstring(L, filename);  /* will be 2nd argument to module */
+  return 2;
 }
 
 
-static int loader_preload (lua_State *L) {
+static int searcher_preload (lua_State *L) {
   const char *name = luaL_checkstring(L, 1);
-  lua_getfield(L, LUA_ENVIRONINDEX, "preload");
-  if (!lua_istable(L, -1))
-    luaL_error(L, LUA_QL("package.preload") " must be a table");
+  lua_getfield(L, LUA_REGISTRYINDEX, "_PRELOAD");
   lua_getfield(L, -1, name);
   if (lua_isnil(L, -1))  /* not found? */
     lua_pushfstring(L, "\n\tno field package.preload['%s']", name);
@@ -444,48 +444,42 @@ static int loader_preload (lua_State *L) {
 }
 
 
-static const int sentinel_ = 0;
-#define sentinel	((void *)&sentinel_)
-
-
 static int ll_require (lua_State *L) {
   const char *name = luaL_checkstring(L, 1);
   int i;
   lua_settop(L, 1);  /* _LOADED table will be at index 2 */
   lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
   lua_getfield(L, 2, name);
-  if (lua_toboolean(L, -1)) {  /* is it there? */
-    if (lua_touserdata(L, -1) == sentinel)  /* check loops */
-      luaL_error(L, "loop or previous error loading module " LUA_QS, name);
+  if (lua_toboolean(L, -1))  /* is it there? */
     return 1;  /* package is already loaded */
-  }
-  /* else must load it; iterate over available loaders */
-  lua_getfield(L, LUA_ENVIRONINDEX, "loaders");
+  /* else must load it; iterate over available seachers to find a loader */
+  lua_getfield(L, lua_upvalueindex(1), "searchers");
   if (!lua_istable(L, -1))
-    luaL_error(L, LUA_QL("package.loaders") " must be a table");
+    luaL_error(L, LUA_QL("package.searchers") " must be a table");
   lua_pushliteral(L, "");  /* error message accumulator */
   for (i=1; ; i++) {
-    lua_rawgeti(L, -2, i);  /* get a loader */
-    if (lua_isnil(L, -1))
+    lua_rawgeti(L, -2, i);  /* get a seacher */
+    if (lua_isnil(L, -1))  /* no more searchers? */
       luaL_error(L, "module " LUA_QS " not found:%s",
                     name, lua_tostring(L, -2));
     lua_pushstring(L, name);
-    lua_call(L, 1, 1);  /* call it */
-    if (lua_isfunction(L, -1))  /* did it find module? */
-      break;  /* module loaded successfully */
-    else if (lua_isstring(L, -1))  /* loader returned error message? */
-      lua_concat(L, 2);  /* accumulate it */
+    lua_call(L, 1, 2);  /* call it */
+    if (lua_isfunction(L, -2))  /* did it find a loader? */
+      break;  /* module loader found */
+    else if (lua_isstring(L, -2)) {  /* searcher returned error message? */
+      lua_pop(L, 1);  /* remove extra return */
+      lua_concat(L, 2);  /* accumulate error message */
+    }
     else
-      lua_pop(L, 1);
+      lua_pop(L, 2);  /* remove both returns */
   }
-  lua_pushlightuserdata(L, sentinel);
-  lua_setfield(L, 2, name);  /* _LOADED[name] = sentinel */
-  lua_pushstring(L, name);  /* pass name as argument to module */
-  lua_call(L, 1, 1);  /* run loaded module */
+  lua_pushstring(L, name);  /* pass name as argument to module loader */
+  lua_insert(L, -2);  /* name is 1st argument (before search data) */
+  lua_call(L, 2, 1);  /* run loader to load module */
   if (!lua_isnil(L, -1))  /* non-nil return? */
     lua_setfield(L, 2, name);  /* _LOADED[name] = returned value */
   lua_getfield(L, 2, name);
-  if (lua_touserdata(L, -1) == sentinel) {   /* module did not set a value? */
+  if (lua_isnil(L, -1)) {   /* module did not set a value? */
     lua_pushboolean(L, 1);  /* use true as result */
     lua_pushvalue(L, -1);  /* extra copy to be returned */
     lua_setfield(L, 2, name);  /* _LOADED[name] = true */
@@ -502,17 +496,20 @@ static int ll_require (lua_State *L) {
 ** 'module' function
 ** =======================================================
 */
-  
+#if defined(LUA_COMPAT_MODULE)
 
-static void setfenv (lua_State *L) {
+/*
+** changes the environment variable of calling function
+*/
+static void set_env (lua_State *L) {
   lua_Debug ar;
   if (lua_getstack(L, 1, &ar) == 0 ||
       lua_getinfo(L, "f", &ar) == 0 ||  /* get calling function */
       lua_iscfunction(L, -1))
     luaL_error(L, LUA_QL("module") " not called from a Lua function");
-  lua_pushvalue(L, -2);
-  lua_setfenv(L, -2);
-  lua_pop(L, 1);
+  lua_pushvalue(L, -2);  /* copy new environment table to top */
+  lua_setupvalue(L, -2, 1);
+  lua_pop(L, 1);  /* remove function */
 }
 
 
@@ -543,17 +540,8 @@ static void modinit (lua_State *L, const char *modname) {
 
 static int ll_module (lua_State *L) {
   const char *modname = luaL_checkstring(L, 1);
-  int loaded = lua_gettop(L) + 1;  /* index of _LOADED table */
-  lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
-  lua_getfield(L, loaded, modname);  /* get _LOADED[modname] */
-  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, modname, 1) != NULL)
-      return luaL_error(L, "name conflict for module " LUA_QS, modname);
-    lua_pushvalue(L, -1);
-    lua_setfield(L, loaded, modname);  /* _LOADED[modname] = new table */
-  }
+  int lastarg = lua_gettop(L);  /* last parameter */
+  luaL_pushmodule(L, modname, 1);  /* get/create module table */
   /* check whether table already has a _NAME field */
   lua_getfield(L, -1, "_NAME");
   if (!lua_isnil(L, -1))  /* is table an initialized module? */
@@ -563,9 +551,9 @@ static int ll_module (lua_State *L) {
     modinit(L, modname);
   }
   lua_pushvalue(L, -1);
-  setfenv(L);
-  dooptions(L, loaded - 1);
-  return 0;
+  set_env(L);
+  dooptions(L, lastarg);
+  return 1;
 }
 
 
@@ -576,12 +564,12 @@ static int ll_seeall (lua_State *L) {
     lua_pushvalue(L, -1);
     lua_setmetatable(L, 1);
   }
-  lua_pushvalue(L, LUA_GLOBALSINDEX);
+  lua_pushglobaltable(L);
   lua_setfield(L, -2, "__index");  /* mt.__index = _G */
   return 0;
 }
 
-
+#endif
 /* }====================================================== */
 
 
@@ -589,15 +577,17 @@ static int ll_seeall (lua_State *L) {
 /* auxiliary mark (for internal use) */
 #define AUXMARK		"\1"
 
-static void setpath (lua_State *L, const char *fieldname, const char *envname,
-                                   const char *def) {
-  const char *path = getenv(envname);
+static void setpath (lua_State *L, const char *fieldname, const char *envname1,
+                                   const char *envname2, const char *def) {
+  const char *path = getenv(envname1);
+  if (path == NULL)  /* no environment variable? */
+    path = getenv(envname2);  /* try alternative name */
   if (path == NULL)  /* no environment variable? */
     lua_pushstring(L, def);  /* use default */
   else {
     /* replace ";;" by ";AUXMARK;" and then AUXMARK by default path */
-    path = luaL_gsub(L, path, LUA_PATHSEP LUA_PATHSEP,
-                              LUA_PATHSEP AUXMARK LUA_PATHSEP);
+    path = luaL_gsub(L, path, LUA_PATH_SEP LUA_PATH_SEP,
+                              LUA_PATH_SEP AUXMARK LUA_PATH_SEP);
     luaL_gsub(L, path, AUXMARK, def);
     lua_remove(L, -2);
   }
@@ -608,59 +598,66 @@ static void setpath (lua_State *L, const char *fieldname, const char *envname,
 
 static const luaL_Reg pk_funcs[] = {
   {"loadlib", ll_loadlib},
+  {"searchpath", ll_searchpath},
+#if defined(LUA_COMPAT_MODULE)
   {"seeall", ll_seeall},
+#endif
   {NULL, NULL}
 };
 
 
 static const luaL_Reg ll_funcs[] = {
+#if defined(LUA_COMPAT_MODULE)
   {"module", ll_module},
+#endif
   {"require", ll_require},
   {NULL, NULL}
 };
 
 
-static const lua_CFunction loaders[] =
-  {loader_preload, loader_Lua, loader_C, loader_Croot, NULL};
+static const lua_CFunction searchers[] =
+  {searcher_preload, searcher_Lua, searcher_C, searcher_Croot, NULL};
 
 
-LUALIB_API int luaopen_package (lua_State *L) {
+LUAMOD_API int luaopen_package (lua_State *L) {
   int i;
   /* create new type _LOADLIB */
   luaL_newmetatable(L, "_LOADLIB");
   lua_pushcfunction(L, gctm);
   lua_setfield(L, -2, "__gc");
   /* create `package' table */
-  luaL_register(L, LUA_LOADLIBNAME, pk_funcs);
-#if defined(LUA_COMPAT_LOADLIB) 
-  lua_getfield(L, -1, "loadlib");
-  lua_setfield(L, LUA_GLOBALSINDEX, "loadlib");
-#endif
-  lua_pushvalue(L, -1);
-  lua_replace(L, LUA_ENVIRONINDEX);
-  /* create `loaders' table */
-  lua_createtable(L, sizeof(loaders)/sizeof(loaders[0]) - 1, 0);
-  /* fill it with pre-defined loaders */
-  for (i=0; loaders[i] != NULL; i++) {
-    lua_pushcfunction(L, loaders[i]);
+  luaL_newlib(L, pk_funcs);
+  /* create 'searchers' table */
+  lua_createtable(L, sizeof(searchers)/sizeof(searchers[0]) - 1, 0);
+  /* fill it with pre-defined searchers */
+  for (i=0; searchers[i] != NULL; i++) {
+    lua_pushvalue(L, -2);  /* set 'package' as upvalue for all searchers */
+    lua_pushcclosure(L, searchers[i], 1);
     lua_rawseti(L, -2, i+1);
   }
-  lua_setfield(L, -2, "loaders");  /* put it in field `loaders' */
-  setpath(L, "path", LUA_PATH, LUA_PATH_DEFAULT);  /* set field `path' */
-  setpath(L, "cpath", LUA_CPATH, LUA_CPATH_DEFAULT); /* set field `cpath' */
+#if defined(LUA_COMPAT_LOADERS)
+  lua_pushvalue(L, -1);  /* make a copy of 'searchers' table */
+  lua_setfield(L, -3, "loaders");  /* put it in field `loaders' */
+#endif
+  lua_setfield(L, -2, "searchers");  /* put it in field 'searchers' */
+  /* set field 'path' */
+  setpath(L, "path", LUA_PATHVERSION, LUA_PATH, LUA_PATH_DEFAULT);
+  /* set field 'cpath' */
+  setpath(L, "cpath", LUA_CPATHVERSION, LUA_CPATH, LUA_CPATH_DEFAULT);
   /* store config information */
-  lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATHSEP "\n" LUA_PATH_MARK "\n"
-                     LUA_EXECDIR "\n" LUA_IGMARK);
+  lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATH_SEP "\n" LUA_PATH_MARK "\n"
+                     LUA_EXEC_DIR "\n" LUA_IGMARK "\n");
   lua_setfield(L, -2, "config");
   /* set field `loaded' */
-  luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 2);
+  luaL_getsubtable(L, LUA_REGISTRYINDEX, "_LOADED");
   lua_setfield(L, -2, "loaded");
   /* set field `preload' */
-  lua_newtable(L);
+  luaL_getsubtable(L, LUA_REGISTRYINDEX, "_PRELOAD");
   lua_setfield(L, -2, "preload");
-  lua_pushvalue(L, LUA_GLOBALSINDEX);
-  luaL_register(L, NULL, ll_funcs);  /* open lib into global table */
-  lua_pop(L, 1);
+  lua_pushglobaltable(L);
+  lua_pushvalue(L, -2);  /* set 'package' as upvalue for next lib */
+  luaL_setfuncs(L, ll_funcs, 1);  /* open lib into global table */
+  lua_pop(L, 1);  /* pop global table */
   return 1;  /* return 'package' table */
 }
 
diff --git a/src/loadlib_rel.c b/src/loadlib_rel.c
index 5ba8d23..9ebd8cc 100644
--- a/src/loadlib_rel.c
+++ b/src/loadlib_rel.c
@@ -1,11 +1,11 @@
 /*
-** $Id: loadlib.c,v 1.52.1.3 2008/08/06 13:29:28 roberto Exp $
+** $Id: loadlib.c,v 1.100 2011/07/05 12:49:35 roberto Exp $
 ** Dynamic library loader for Lua
 ** See Copyright Notice in lua.h
 **
 ** This module contains an implementation of loadlib for Unix systems
-** that have dlfcn, an implementation for Darwin (Mac OS X), an
-** implementation for Windows, and a stub for other systems.
+** that have dlfcn, an implementation for Windows, and a stub for other
+** systems.
 */
 
 
@@ -22,6 +22,47 @@
 #include "lualib.h"
 
 
+/*
+** LUA_PATH and LUA_CPATH are the names of the environment
+** variables that Lua check to set its paths.
+*/
+#if !defined(LUA_PATH)
+#define LUA_PATH	"LUA_PATH"
+#endif
+
+#if !defined(LUA_CPATH)
+#define LUA_CPATH	"LUA_CPATH"
+#endif
+
+#define LUA_PATHSUFFIX		"_" LUA_VERSION_MAJOR "_" LUA_VERSION_MINOR
+
+#define LUA_PATHVERSION		LUA_PATH LUA_PATHSUFFIX
+#define LUA_CPATHVERSION	LUA_CPATH LUA_PATHSUFFIX
+
+/*
+** LUA_PATH_SEP is the character that separates templates in a path.
+** LUA_PATH_MARK is the string that marks the substitution points in a
+** template.
+** LUA_EXEC_DIR in a Windows path is replaced by the executable's
+** directory.
+** LUA_IGMARK is a mark to ignore all before it when building the
+** luaopen_ function name.
+*/
+#if !defined (LUA_PATH_SEP)
+#define LUA_PATH_SEP		";"
+#endif
+#if !defined (LUA_PATH_MARK)
+#define LUA_PATH_MARK		"?"
+#endif
+#if !defined (LUA_EXEC_DIR)
+#define LUA_EXEC_DIR		"!"
+#endif
+#if !defined (LUA_IGMARK)
+#define LUA_IGMARK		"-"
+#endif
+
+
+
 /* prefix for open functions in C libraries */
 #define LUA_POF		"luaopen_"
 
@@ -39,8 +80,11 @@
 #define ERRLIB		1
 #define ERRFUNC		2
 
+/*
+** system-dependent functions
+*/
 static void ll_unloadlib (void *lib);
-static void *ll_load (lua_State *L, const char *path);
+static void *ll_load (lua_State *L, const char *path, int seeglb);
 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym);
 static void setprogdir (lua_State *L);
 
@@ -112,14 +156,13 @@ static void setprogdir (lua_State *L) {
     lua_setglobal(L, "_PROGDIR");
     
     // Replace the relative path placeholder
-    luaL_gsub(L, lua_tostring(L, -1), LUA_EXECDIR, progdir);
+    luaL_gsub(L, lua_tostring(L, -1), LUA_EXEC_DIR, progdir);
     lua_remove(L, -2);
   }
 }
 
-/* }====================================================== */
 
-#if defined(LUA_DL_DLOPEN)
+#if defined(LUA_USE_DLOPEN)
 /*
 ** {========================================================================
 ** This is an implementation of loadlib based on the dlfcn interface.
@@ -130,14 +173,14 @@ static void setprogdir (lua_State *L) {
 */
 
 #include <dlfcn.h>
-#include <sys/stat.h> 
 
 static void ll_unloadlib (void *lib) {
   dlclose(lib);
 }
 
-static void *ll_load (lua_State *L, const char *path) {
-  void *lib = dlopen(path, RTLD_NOW);
+
+static void *ll_load (lua_State *L, const char *path, int seeglb) {
+  void *lib = dlopen(path, RTLD_NOW | (seeglb ? RTLD_GLOBAL : 0));
   if (lib == NULL) lua_pushstring(L, dlerror());
   return lib;
 }
@@ -162,30 +205,38 @@ static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
 
 #include <windows.h>
 
+/*
+** optional flags for LoadLibraryEx
+*/
+#if !defined(LUA_LLE_FLAGS)
+#define LUA_LLE_FLAGS	0
+#endif
+
 static void pusherror (lua_State *L) {
   int error = GetLastError();
   char buffer[128];
   if (FormatMessageA(FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_FROM_SYSTEM,
-      NULL, error, 0, buffer, sizeof(buffer), NULL))
+      NULL, error, 0, buffer, sizeof(buffer)/sizeof(char), NULL))
     lua_pushstring(L, buffer);
   else
     lua_pushfstring(L, "system error %d\n", error);
 }
 
 static void ll_unloadlib (void *lib) {
-  FreeLibrary((HINSTANCE)lib);
+  FreeLibrary((HMODULE)lib);
 }
 
 
-static void *ll_load (lua_State *L, const char *path) {
-  HINSTANCE lib = LoadLibraryA(path);
+static void *ll_load (lua_State *L, const char *path, int seeglb) {
+  HMODULE lib = LoadLibraryExA(path, NULL, LUA_LLE_FLAGS);
+  (void)(seeglb);  /* symbols are 'global' by default */
   if (lib == NULL) pusherror(L);
   return lib;
 }
 
 
 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
-  lua_CFunction f = (lua_CFunction)GetProcAddress((HINSTANCE)lib, sym);
+  lua_CFunction f = (lua_CFunction)GetProcAddress((HMODULE)lib, sym);
   if (f == NULL) pusherror(L);
   return f;
 }
@@ -193,88 +244,6 @@ static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
 /* }====================================================== */
 
 
-
-#elif defined(LUA_DL_DYLD)
-/*
-** {======================================================================
-** Native Mac OS X / Darwin Implementation
-** =======================================================================
-*/
-
-#include <mach-o/dyld.h>
-
-
-/* Mac appends a `_' before C function names */
-#undef POF
-#define POF	"_" LUA_POF
-
-
-static void pusherror (lua_State *L) {
-  const char *err_str;
-  const char *err_file;
-  NSLinkEditErrors err;
-  int err_num;
-  NSLinkEditError(&err, &err_num, &err_file, &err_str);
-  lua_pushstring(L, err_str);
-}
-
-
-static const char *errorfromcode (NSObjectFileImageReturnCode ret) {
-  switch (ret) {
-    case NSObjectFileImageInappropriateFile:
-      return "file is not a bundle";
-    case NSObjectFileImageArch:
-      return "library is for wrong CPU type";
-    case NSObjectFileImageFormat:
-      return "bad format";
-    case NSObjectFileImageAccess:
-      return "cannot access file";
-    case NSObjectFileImageFailure:
-    default:
-      return "unable to load library";
-  }
-}
-
-
-static void ll_unloadlib (void *lib) {
-  NSUnLinkModule((NSModule)lib, NSUNLINKMODULE_OPTION_RESET_LAZY_REFERENCES);
-}
-
-
-static void *ll_load (lua_State *L, const char *path) {
-  NSObjectFileImage img;
-  NSObjectFileImageReturnCode ret;
-  /* this would be a rare case, but prevents crashing if it happens */
-  if(!_dyld_present()) {
-    lua_pushliteral(L, "dyld not present");
-    return NULL;
-  }
-  ret = NSCreateObjectFileImageFromFile(path, &img);
-  if (ret == NSObjectFileImageSuccess) {
-    NSModule mod = NSLinkModule(img, path, NSLINKMODULE_OPTION_PRIVATE |
-                       NSLINKMODULE_OPTION_RETURN_ON_ERROR);
-    NSDestroyObjectFileImage(img);
-    if (mod == NULL) pusherror(L);
-    return mod;
-  }
-  lua_pushstring(L, errorfromcode(ret));
-  return NULL;
-}
-
-
-static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
-  NSSymbol nss = NSLookupSymbolInModule((NSModule)lib, sym);
-  if (nss == NULL) {
-    lua_pushfstring(L, "symbol " LUA_QS " not found", sym);
-    return NULL;
-  }
-  return (lua_CFunction)NSAddressOfSymbol(nss);
-}
-
-/* }====================================================== */
-
-
-
 #else
 /*
 ** {======================================================
@@ -290,19 +259,19 @@ static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
 
 
 static void ll_unloadlib (void *lib) {
-  (void)lib;  /* to avoid warnings */
+  (void)(lib);  /* to avoid warnings */
 }
 
 
-static void *ll_load (lua_State *L, const char *path) {
-  (void)path;  /* to avoid warnings */
+static void *ll_load (lua_State *L, const char *path, int seeglb) {
+  (void)(path); (void)(seeglb);  /* to avoid warnings */
   lua_pushliteral(L, DLMSG);
   return NULL;
 }
 
 
 static lua_CFunction ll_sym (lua_State *L, void *lib, const char *sym) {
-  (void)lib; (void)sym;  /* to avoid warnings */
+  (void)(lib); (void)(sym);  /* to avoid warnings */
   lua_pushliteral(L, DLMSG);
   return NULL;
 }
@@ -319,11 +288,10 @@ static void **ll_register (lua_State *L, const char *path) {
   if (!lua_isnil(L, -1))  /* is there an entry? */
     plib = (void **)lua_touserdata(L, -1);
   else {  /* no entry yet; create one */
-    lua_pop(L, 1);
+    lua_pop(L, 1);  /* remove result from gettable */
     plib = (void **)lua_newuserdata(L, sizeof(const void *));
     *plib = NULL;
-    luaL_getmetatable(L, "_LOADLIB");
-    lua_setmetatable(L, -2);
+    luaL_setmetatable(L, "_LOADLIB");
     lua_pushfstring(L, "%s%s", LIBPREFIX, path);
     lua_pushvalue(L, -2);
     lua_settable(L, LUA_REGISTRYINDEX);
@@ -346,15 +314,18 @@ static int gctm (lua_State *L) {
 
 static int ll_loadfunc (lua_State *L, const char *path, const char *sym) {
   void **reg = ll_register(L, path);
-  if (*reg == NULL) *reg = ll_load(L, path);
-  if (*reg == NULL)
-    return ERRLIB;  /* unable to load library */
+  if (*reg == NULL) *reg = ll_load(L, path, *sym == '*');
+  if (*reg == NULL) return ERRLIB;  /* unable to load library */
+  if (*sym == '*') {  /* loading only library (no function)? */
+    lua_pushboolean(L, 1);  /* return 'true' */
+    return 0;  /* no errors */
+  }
   else {
     lua_CFunction f = ll_sym(L, *reg, sym);
     if (f == NULL)
       return ERRFUNC;  /* unable to find function */
-    lua_pushcfunction(L, f);
-    return 0;  /* return function */
+    lua_pushcfunction(L, f);  /* else create new function */
+    return 0;  /* no errors */
   }
 }
 
@@ -392,27 +363,24 @@ static int readable (const char *filename) {
 
 static const char *pushnexttemplate (lua_State *L, const char *path) {
   const char *l;
-  while (*path == *LUA_PATHSEP) path++;  /* skip separators */
+  while (*path == *LUA_PATH_SEP) path++;  /* skip separators */
   if (*path == '\0') return NULL;  /* no more templates */
-  l = strchr(path, *LUA_PATHSEP);  /* find next separator */
+  l = strchr(path, *LUA_PATH_SEP);  /* find next separator */
   if (l == NULL) l = path + strlen(path);
   lua_pushlstring(L, path, l - path);  /* template */
   return l;
 }
 
 
-static const char *findfile (lua_State *L, const char *name,
-                                           const char *pname) {
-  const char *path;
-  name = luaL_gsub(L, name, ".", LUA_DIRSEP);
-  lua_getfield(L, LUA_ENVIRONINDEX, pname);
-  path = lua_tostring(L, -1);
-  if (path == NULL)
-    luaL_error(L, LUA_QL("package.%s") " must be a string", pname);
+static const char *searchpath (lua_State *L, const char *name,
+                                             const char *path,
+                                             const char *sep) {
+  if (*sep != '\0')  /* non-empty separator? */
+    name = luaL_gsub(L, name, sep, LUA_DIRSEP);  /* replace it by proper one */
   lua_pushliteral(L, "");  /* error accumulator */
   while ((path = pushnexttemplate(L, path)) != NULL) {
-    const char *filename;
-    filename = luaL_gsub(L, lua_tostring(L, -1), LUA_PATH_MARK, name);
+    const char *filename = luaL_gsub(L, lua_tostring(L, -1),
+                                     LUA_PATH_MARK, name);
     lua_remove(L, -2);  /* remove path template */
     if (readable(filename))  /* does file exist and is readable? */
       return filename;  /* return that file name */
@@ -424,48 +392,78 @@ static const char *findfile (lua_State *L, const char *name,
 }
 
 
-static void loaderror (lua_State *L, const char *filename) {
-  luaL_error(L, "error loading module " LUA_QS " from file " LUA_QS ":\n\t%s",
-                lua_tostring(L, 1), filename, lua_tostring(L, -1));
+static int ll_searchpath (lua_State *L) {
+  const char *f = searchpath(L, luaL_checkstring(L, 1),
+                                luaL_checkstring(L, 2),
+                                luaL_optstring(L, 3, "."));
+  if (f != NULL) return 1;
+  else {  /* error message is on top of the stack */
+    lua_pushnil(L);
+    lua_insert(L, -2);
+    return 2;  /* return nil + error message */
+  }
 }
 
 
-static int loader_Lua (lua_State *L) {
+static const char *findfile (lua_State *L, const char *name,
+                                           const char *pname) {
+  const char *path;
+  lua_getfield(L, lua_upvalueindex(1), pname);
+  path = lua_tostring(L, -1);
+  if (path == NULL)
+    luaL_error(L, LUA_QL("package.%s") " must be a string", pname);
+  return searchpath(L, name, path, ".");
+}
+
+
+static int checkload (lua_State *L, int stat, const char *filename) {
+  if (stat) {  /* module loaded successfully? */
+    lua_pushstring(L, filename);  /* will be 2nd argument to module */
+    return 2;  /* return open function and file name */
+  }
+  else
+    return luaL_error(L, "error loading module " LUA_QS
+                         " from file " LUA_QS ":\n\t%s",
+                          lua_tostring(L, 1), filename, lua_tostring(L, -1));
+}
+
+
+static int searcher_Lua (lua_State *L) {
   const char *filename;
   const char *name = luaL_checkstring(L, 1);
   filename = findfile(L, name, "path");
-  if (filename == NULL) return 1;  /* library not found in this path */
-  if (luaL_loadfile(L, filename) != 0)
-    loaderror(L, filename);
-  return 1;  /* library loaded successfully */
+  if (filename == NULL) return 1;  /* module not found in this path */
+  return checkload(L, (luaL_loadfile(L, filename) == LUA_OK), filename);
 }
 
 
-static const char *mkfuncname (lua_State *L, const char *modname) {
+static int loadfunc (lua_State *L, const char *filename, const char *modname) {
   const char *funcname;
-  const char *mark = strchr(modname, *LUA_IGMARK);
-  if (mark) modname = mark + 1;
-  funcname = luaL_gsub(L, modname, ".", LUA_OFSEP);
-  funcname = lua_pushfstring(L, POF"%s", funcname);
-  lua_remove(L, -2);  /* remove 'gsub' result */
-  return funcname;
+  const char *mark;
+  modname = luaL_gsub(L, modname, ".", LUA_OFSEP);
+  mark = strchr(modname, *LUA_IGMARK);
+  if (mark) {
+    int stat;
+    funcname = lua_pushlstring(L, modname, mark - modname);
+    funcname = lua_pushfstring(L, POF"%s", funcname);
+    stat = ll_loadfunc(L, filename, funcname);
+    if (stat != ERRFUNC) return stat;
+    modname = mark + 1;  /* else go ahead and try old-style name */
+  }
+  funcname = lua_pushfstring(L, POF"%s", modname);
+  return ll_loadfunc(L, filename, funcname);
 }
 
 
-static int loader_C (lua_State *L) {
-  const char *funcname;
+static int searcher_C (lua_State *L) {
   const char *name = luaL_checkstring(L, 1);
   const char *filename = findfile(L, name, "cpath");
-  if (filename == NULL) return 1;  /* library not found in this path */
-  funcname = mkfuncname(L, name);
-  if (ll_loadfunc(L, filename, funcname) != 0)
-    loaderror(L, filename);
-  return 1;  /* library loaded successfully */
+  if (filename == NULL) return 1;  /* module not found in this path */
+  return checkload(L, (loadfunc(L, filename, name) == 0), filename);
 }
 
 
-static int loader_Croot (lua_State *L) {
-  const char *funcname;
+static int searcher_Croot (lua_State *L) {
   const char *filename;
   const char *name = luaL_checkstring(L, 1);
   const char *p = strchr(name, '.');
@@ -474,22 +472,23 @@ static int loader_Croot (lua_State *L) {
   lua_pushlstring(L, name, p - name);
   filename = findfile(L, lua_tostring(L, -1), "cpath");
   if (filename == NULL) return 1;  /* root not found */
-  funcname = mkfuncname(L, name);
-  if ((stat = ll_loadfunc(L, filename, funcname)) != 0) {
-    if (stat != ERRFUNC) loaderror(L, filename);  /* real error */
-    lua_pushfstring(L, "\n\tno module " LUA_QS " in file " LUA_QS,
-                       name, filename);
-    return 1;  /* function not found */
+  if ((stat = loadfunc(L, filename, name)) != 0) {
+    if (stat != ERRFUNC)
+      return checkload(L, 0, filename);  /* real error */
+    else {  /* open function not found */
+      lua_pushfstring(L, "\n\tno module " LUA_QS " in file " LUA_QS,
+                         name, filename);
+      return 1;
+    }
   }
-  return 1;
+  lua_pushstring(L, filename);  /* will be 2nd argument to module */
+  return 2;
 }
 
 
-static int loader_preload (lua_State *L) {
+static int searcher_preload (lua_State *L) {
   const char *name = luaL_checkstring(L, 1);
-  lua_getfield(L, LUA_ENVIRONINDEX, "preload");
-  if (!lua_istable(L, -1))
-    luaL_error(L, LUA_QL("package.preload") " must be a table");
+  lua_getfield(L, LUA_REGISTRYINDEX, "_PRELOAD");
   lua_getfield(L, -1, name);
   if (lua_isnil(L, -1))  /* not found? */
     lua_pushfstring(L, "\n\tno field package.preload['%s']", name);
@@ -497,48 +496,42 @@ static int loader_preload (lua_State *L) {
 }
 
 
-static const int sentinel_ = 0;
-#define sentinel	((void *)&sentinel_)
-
-
 static int ll_require (lua_State *L) {
   const char *name = luaL_checkstring(L, 1);
   int i;
   lua_settop(L, 1);  /* _LOADED table will be at index 2 */
   lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
   lua_getfield(L, 2, name);
-  if (lua_toboolean(L, -1)) {  /* is it there? */
-    if (lua_touserdata(L, -1) == sentinel)  /* check loops */
-      luaL_error(L, "loop or previous error loading module " LUA_QS, name);
+  if (lua_toboolean(L, -1))  /* is it there? */
     return 1;  /* package is already loaded */
-  }
-  /* else must load it; iterate over available loaders */
-  lua_getfield(L, LUA_ENVIRONINDEX, "loaders");
+  /* else must load it; iterate over available seachers to find a loader */
+  lua_getfield(L, lua_upvalueindex(1), "searchers");
   if (!lua_istable(L, -1))
-    luaL_error(L, LUA_QL("package.loaders") " must be a table");
+    luaL_error(L, LUA_QL("package.searchers") " must be a table");
   lua_pushliteral(L, "");  /* error message accumulator */
   for (i=1; ; i++) {
-    lua_rawgeti(L, -2, i);  /* get a loader */
-    if (lua_isnil(L, -1))
+    lua_rawgeti(L, -2, i);  /* get a seacher */
+    if (lua_isnil(L, -1))  /* no more searchers? */
       luaL_error(L, "module " LUA_QS " not found:%s",
                     name, lua_tostring(L, -2));
     lua_pushstring(L, name);
-    lua_call(L, 1, 1);  /* call it */
-    if (lua_isfunction(L, -1))  /* did it find module? */
-      break;  /* module loaded successfully */
-    else if (lua_isstring(L, -1))  /* loader returned error message? */
-      lua_concat(L, 2);  /* accumulate it */
+    lua_call(L, 1, 2);  /* call it */
+    if (lua_isfunction(L, -2))  /* did it find a loader? */
+      break;  /* module loader found */
+    else if (lua_isstring(L, -2)) {  /* searcher returned error message? */
+      lua_pop(L, 1);  /* remove extra return */
+      lua_concat(L, 2);  /* accumulate error message */
+    }
     else
-      lua_pop(L, 1);
+      lua_pop(L, 2);  /* remove both returns */
   }
-  lua_pushlightuserdata(L, sentinel);
-  lua_setfield(L, 2, name);  /* _LOADED[name] = sentinel */
-  lua_pushstring(L, name);  /* pass name as argument to module */
-  lua_call(L, 1, 1);  /* run loaded module */
+  lua_pushstring(L, name);  /* pass name as argument to module loader */
+  lua_insert(L, -2);  /* name is 1st argument (before search data) */
+  lua_call(L, 2, 1);  /* run loader to load module */
   if (!lua_isnil(L, -1))  /* non-nil return? */
     lua_setfield(L, 2, name);  /* _LOADED[name] = returned value */
   lua_getfield(L, 2, name);
-  if (lua_touserdata(L, -1) == sentinel) {   /* module did not set a value? */
+  if (lua_isnil(L, -1)) {   /* module did not set a value? */
     lua_pushboolean(L, 1);  /* use true as result */
     lua_pushvalue(L, -1);  /* extra copy to be returned */
     lua_setfield(L, 2, name);  /* _LOADED[name] = true */
@@ -555,17 +548,20 @@ static int ll_require (lua_State *L) {
 ** 'module' function
 ** =======================================================
 */
-  
+#if defined(LUA_COMPAT_MODULE)
 
-static void setfenv (lua_State *L) {
+/*
+** changes the environment variable of calling function
+*/
+static void set_env (lua_State *L) {
   lua_Debug ar;
   if (lua_getstack(L, 1, &ar) == 0 ||
       lua_getinfo(L, "f", &ar) == 0 ||  /* get calling function */
       lua_iscfunction(L, -1))
     luaL_error(L, LUA_QL("module") " not called from a Lua function");
-  lua_pushvalue(L, -2);
-  lua_setfenv(L, -2);
-  lua_pop(L, 1);
+  lua_pushvalue(L, -2);  /* copy new environment table to top */
+  lua_setupvalue(L, -2, 1);
+  lua_pop(L, 1);  /* remove function */
 }
 
 
@@ -596,17 +592,8 @@ static void modinit (lua_State *L, const char *modname) {
 
 static int ll_module (lua_State *L) {
   const char *modname = luaL_checkstring(L, 1);
-  int loaded = lua_gettop(L) + 1;  /* index of _LOADED table */
-  lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
-  lua_getfield(L, loaded, modname);  /* get _LOADED[modname] */
-  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, modname, 1) != NULL)
-      return luaL_error(L, "name conflict for module " LUA_QS, modname);
-    lua_pushvalue(L, -1);
-    lua_setfield(L, loaded, modname);  /* _LOADED[modname] = new table */
-  }
+  int lastarg = lua_gettop(L);  /* last parameter */
+  luaL_pushmodule(L, modname, 1);  /* get/create module table */
   /* check whether table already has a _NAME field */
   lua_getfield(L, -1, "_NAME");
   if (!lua_isnil(L, -1))  /* is table an initialized module? */
@@ -616,9 +603,9 @@ static int ll_module (lua_State *L) {
     modinit(L, modname);
   }
   lua_pushvalue(L, -1);
-  setfenv(L);
-  dooptions(L, loaded - 1);
-  return 0;
+  set_env(L);
+  dooptions(L, lastarg);
+  return 1;
 }
 
 
@@ -629,12 +616,12 @@ static int ll_seeall (lua_State *L) {
     lua_pushvalue(L, -1);
     lua_setmetatable(L, 1);
   }
-  lua_pushvalue(L, LUA_GLOBALSINDEX);
+  lua_pushglobaltable(L);
   lua_setfield(L, -2, "__index");  /* mt.__index = _G */
   return 0;
 }
 
-
+#endif
 /* }====================================================== */
 
 
@@ -642,15 +629,17 @@ static int ll_seeall (lua_State *L) {
 /* auxiliary mark (for internal use) */
 #define AUXMARK		"\1"
 
-static void setpath (lua_State *L, const char *fieldname, const char *envname,
-                                   const char *def) {
-  const char *path = getenv(envname);
+static void setpath (lua_State *L, const char *fieldname, const char *envname1,
+                                   const char *envname2, const char *def) {
+  const char *path = getenv(envname1);
+  if (path == NULL)  /* no environment variable? */
+    path = getenv(envname2);  /* try alternative name */
   if (path == NULL)  /* no environment variable? */
     lua_pushstring(L, def);  /* use default */
   else {
     /* replace ";;" by ";AUXMARK;" and then AUXMARK by default path */
-    path = luaL_gsub(L, path, LUA_PATHSEP LUA_PATHSEP,
-                              LUA_PATHSEP AUXMARK LUA_PATHSEP);
+    path = luaL_gsub(L, path, LUA_PATH_SEP LUA_PATH_SEP,
+                              LUA_PATH_SEP AUXMARK LUA_PATH_SEP);
     luaL_gsub(L, path, AUXMARK, def);
     lua_remove(L, -2);
   }
@@ -661,59 +650,66 @@ static void setpath (lua_State *L, const char *fieldname, const char *envname,
 
 static const luaL_Reg pk_funcs[] = {
   {"loadlib", ll_loadlib},
+  {"searchpath", ll_searchpath},
+#if defined(LUA_COMPAT_MODULE)
   {"seeall", ll_seeall},
+#endif
   {NULL, NULL}
 };
 
 
 static const luaL_Reg ll_funcs[] = {
+#if defined(LUA_COMPAT_MODULE)
   {"module", ll_module},
+#endif
   {"require", ll_require},
   {NULL, NULL}
 };
 
 
-static const lua_CFunction loaders[] =
-  {loader_preload, loader_Lua, loader_C, loader_Croot, NULL};
+static const lua_CFunction searchers[] =
+  {searcher_preload, searcher_Lua, searcher_C, searcher_Croot, NULL};
 
 
-LUALIB_API int luaopen_package (lua_State *L) {
+LUAMOD_API int luaopen_package (lua_State *L) {
   int i;
   /* create new type _LOADLIB */
   luaL_newmetatable(L, "_LOADLIB");
   lua_pushcfunction(L, gctm);
   lua_setfield(L, -2, "__gc");
   /* create `package' table */
-  luaL_register(L, LUA_LOADLIBNAME, pk_funcs);
-#if defined(LUA_COMPAT_LOADLIB) 
-  lua_getfield(L, -1, "loadlib");
-  lua_setfield(L, LUA_GLOBALSINDEX, "loadlib");
-#endif
-  lua_pushvalue(L, -1);
-  lua_replace(L, LUA_ENVIRONINDEX);
-  /* create `loaders' table */
-  lua_createtable(L, sizeof(loaders)/sizeof(loaders[0]) - 1, 0);
-  /* fill it with pre-defined loaders */
-  for (i=0; loaders[i] != NULL; i++) {
-    lua_pushcfunction(L, loaders[i]);
+  luaL_newlib(L, pk_funcs);
+  /* create 'searchers' table */
+  lua_createtable(L, sizeof(searchers)/sizeof(searchers[0]) - 1, 0);
+  /* fill it with pre-defined searchers */
+  for (i=0; searchers[i] != NULL; i++) {
+    lua_pushvalue(L, -2);  /* set 'package' as upvalue for all searchers */
+    lua_pushcclosure(L, searchers[i], 1);
     lua_rawseti(L, -2, i+1);
   }
-  lua_setfield(L, -2, "loaders");  /* put it in field `loaders' */
-  setpath(L, "path", LUA_PATH, LUA_PATH_DEFAULT);  /* set field `path' */
-  setpath(L, "cpath", LUA_CPATH, LUA_CPATH_DEFAULT); /* set field `cpath' */
+#if defined(LUA_COMPAT_LOADERS)
+  lua_pushvalue(L, -1);  /* make a copy of 'searchers' table */
+  lua_setfield(L, -3, "loaders");  /* put it in field `loaders' */
+#endif
+  lua_setfield(L, -2, "searchers");  /* put it in field 'searchers' */
+  /* set field 'path' */
+  setpath(L, "path", LUA_PATHVERSION, LUA_PATH, LUA_PATH_DEFAULT);
+  /* set field 'cpath' */
+  setpath(L, "cpath", LUA_CPATHVERSION, LUA_CPATH, LUA_CPATH_DEFAULT);
   /* store config information */
-  lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATHSEP "\n" LUA_PATH_MARK "\n"
-                     LUA_EXECDIR "\n" LUA_IGMARK);
+  lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATH_SEP "\n" LUA_PATH_MARK "\n"
+                     LUA_EXEC_DIR "\n" LUA_IGMARK "\n");
   lua_setfield(L, -2, "config");
   /* set field `loaded' */
-  luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 2);
+  luaL_getsubtable(L, LUA_REGISTRYINDEX, "_LOADED");
   lua_setfield(L, -2, "loaded");
   /* set field `preload' */
-  lua_newtable(L);
+  luaL_getsubtable(L, LUA_REGISTRYINDEX, "_PRELOAD");
   lua_setfield(L, -2, "preload");
-  lua_pushvalue(L, LUA_GLOBALSINDEX);
-  luaL_register(L, NULL, ll_funcs);  /* open lib into global table */
-  lua_pop(L, 1);
+  lua_pushglobaltable(L);
+  lua_pushvalue(L, -2);  /* set 'package' as upvalue for next lib */
+  luaL_setfuncs(L, ll_funcs, 1);  /* open lib into global table */
+  lua_pop(L, 1);  /* pop global table */
   return 1;  /* return 'package' table */
 }
 
diff --git a/src/lobject.c b/src/lobject.c
index 4ff5073..d8cc3ce 100644..100755
--- a/src/lobject.c
+++ b/src/lobject.c
@@ -1,10 +1,9 @@
 /*
-** $Id: lobject.c,v 2.22.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lobject.c,v 2.52 2011/06/24 12:25:02 roberto Exp $
 ** Some generic functions over Lua objects
 ** See Copyright Notice in lua.h
 */
 
-#include <ctype.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -15,6 +14,8 @@
 
 #include "lua.h"
 
+#include "lctype.h"
+#include "ldebug.h"
 #include "ldo.h"
 #include "lmem.h"
 #include "lobject.h"
@@ -24,7 +25,7 @@
 
 
 
-const TValue luaO_nilobject_ = {{NULL}, LUA_TNIL};
+LUAI_DDEF const TValue luaO_nilobject_ = {NILCONSTANT};
 
 
 /*
@@ -32,26 +33,26 @@ const TValue luaO_nilobject_ = {{NULL}, LUA_TNIL};
 ** (eeeeexxx), where the real value is (1xxx) * 2^(eeeee - 1) if
 ** eeeee != 0 and (xxx) otherwise.
 */
-int luaO_int2fb (unsigned int x) {
-  int e = 0;  /* expoent */
-  while (x >= 16) {
+int luaO_int2fb (lu_int32 x) {
+  int e = 0;  /* exponent */
+  if (x < 8) return x;
+  while (x >= 0x10) {
     x = (x+1) >> 1;
     e++;
   }
-  if (x < 8) return x;
-  else return ((e+1) << 3) | (cast_int(x) - 8);
+  return ((e+1) << 3) | (cast_int(x) - 8);
 }
 
 
 /* converts back */
 int luaO_fb2int (int x) {
-  int e = (x >> 3) & 31;
+  int e = (x >> 3) & 0x1f;
   if (e == 0) return x;
-  else return ((x & 7)+8) << (e - 1);
+  else return ((x & 7) + 8) << (e - 1);
 }
 
 
-int luaO_log2 (unsigned int x) {
+int luaO_ceillog2 (unsigned int x) {
   static const lu_byte log_2[256] = {
     0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
     6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
@@ -62,55 +63,120 @@ int luaO_log2 (unsigned int x) {
     8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
     8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8
   };
-  int l = -1;
+  int l = 0;
+  x--;
   while (x >= 256) { l += 8; x >>= 8; }
   return l + log_2[x];
+}
+
+
+lua_Number luaO_arith (int op, lua_Number v1, lua_Number v2) {
+  switch (op) {
+    case LUA_OPADD: return luai_numadd(NULL, v1, v2);
+    case LUA_OPSUB: return luai_numsub(NULL, v1, v2);
+    case LUA_OPMUL: return luai_nummul(NULL, v1, v2);
+    case LUA_OPDIV: return luai_numdiv(NULL, v1, v2);
+    case LUA_OPMOD: return luai_nummod(NULL, v1, v2);
+    case LUA_OPPOW: return luai_numpow(NULL, v1, v2);
+    case LUA_OPUNM: return luai_numunm(NULL, v1);
+    default: lua_assert(0); return 0;
+  }
+}
+
 
+int luaO_hexavalue (int c) {
+  if (lisdigit(c)) return c - '0';
+  else return ltolower(c) - 'a' + 10;
 }
 
 
-int luaO_rawequalObj (const TValue *t1, const TValue *t2) {
-  if (ttype(t1) != ttype(t2)) return 0;
-  else switch (ttype(t1)) {
-    case LUA_TNIL:
-      return 1;
-    case LUA_TNUMBER:
-      return luai_numeq(nvalue(t1), nvalue(t2));
-    case LUA_TBOOLEAN:
-      return bvalue(t1) == bvalue(t2);  /* boolean true must be 1 !! */
-    case LUA_TLIGHTUSERDATA:
-      return pvalue(t1) == pvalue(t2);
-    default:
-      lua_assert(iscollectable(t1));
-      return gcvalue(t1) == gcvalue(t2);
+#if !defined(lua_strx2number)
+
+#include <math.h>
+
+
+static int isneg (const char **s) {
+  if (**s == '-') { (*s)++; return 1; }
+  else if (**s == '+') (*s)++;
+  return 0;
+}
+
+
+static lua_Number readhexa (const char **s, lua_Number r, int *count) {
+  while (lisxdigit(cast_uchar(**s))) {  /* read integer part */
+    r = (r * 16.0) + cast_num(luaO_hexavalue(cast_uchar(*(*s)++)));
+    (*count)++;
   }
+  return r;
 }
 
 
-int luaO_str2d (const char *s, lua_Number *result) {
+/*
+** convert an hexadecimal numeric string to a number, following
+** C99 specification for 'strtod'
+*/
+static lua_Number lua_strx2number (const char *s, char **endptr) {
+  lua_Number r = 0.0;
+  int e = 0, i = 0;
+  int neg = 0;  /* 1 if number is negative */
+  *endptr = cast(char *, s);  /* nothing is valid yet */
+  while (lisspace(cast_uchar(*s))) s++;  /* skip initial spaces */
+  neg = isneg(&s);  /* check signal */
+  if (!(*s == '0' && (*(s + 1) == 'x' || *(s + 1) == 'X')))  /* check '0x' */
+    return 0.0;  /* invalid format (no '0x') */
+  s += 2;  /* skip '0x' */
+  r = readhexa(&s, r, &i);  /* read integer part */
+  if (*s == '.') {
+    s++;  /* skip dot */
+    r = readhexa(&s, r, &e);  /* read fractional part */
+  }
+  if (i == 0 && e == 0)
+    return 0.0;  /* invalid format (no digit) */
+  e *= -4;  /* each fractional digit divides value by 2^-4 */
+  *endptr = cast(char *, s);  /* valid up to here */
+  if (*s == 'p' || *s == 'P') {  /* exponent part? */
+    int exp1 = 0;
+    int neg1;
+    s++;  /* skip 'p' */
+    neg1 = isneg(&s);  /* signal */
+    if (!lisdigit(cast_uchar(*s)))
+      goto ret;  /* must have at least one digit */
+    while (lisdigit(cast_uchar(*s)))  /* read exponent */
+      exp1 = exp1 * 10 + *(s++) - '0';
+    if (neg1) exp1 = -exp1;
+    e += exp1;
+  }
+  *endptr = cast(char *, s);  /* valid up to here */
+ ret:
+  if (neg) r = -r;
+  return ldexp(r, e);
+}
+
+#endif
+
+
+int luaO_str2d (const char *s, size_t len, lua_Number *result) {
   char *endptr;
-  *result = lua_str2number(s, &endptr);
-  if (endptr == s) return 0;  /* conversion failed */
-  if (*endptr == 'x' || *endptr == 'X')  /* maybe an hexadecimal constant? */
-    *result = cast_num(strtoul(s, &endptr, 16));
-  if (*endptr == '\0') return 1;  /* most common case */
-  while (isspace(cast(unsigned char, *endptr))) endptr++;
-  if (*endptr != '\0') return 0;  /* invalid trailing characters? */
-  return 1;
+  if (strpbrk(s, "xX"))  /* hexa? */
+    *result = lua_strx2number(s, &endptr);
+  else
+    *result = lua_str2number(s, &endptr);
+  if (endptr == s) return 0;  /* nothing recognized */
+  while (lisspace(cast_uchar(*endptr))) endptr++;
+  return (endptr == s + len);  /* OK if no trailing characters */
 }
 
 
 
-static void pushstr (lua_State *L, const char *str) {
-  setsvalue2s(L, L->top, luaS_new(L, str));
+static void pushstr (lua_State *L, const char *str, size_t l) {
+  setsvalue2s(L, L->top, luaS_newlstr(L, str, l));
   incr_top(L);
 }
 
 
 /* this function handles only `%d', `%c', %f, %p, and `%s' formats */
 const char *luaO_pushvfstring (lua_State *L, const char *fmt, va_list argp) {
-  int n = 1;
-  pushstr(L, "");
+  int n = 0;
   for (;;) {
     const char *e = strchr(fmt, '%');
     if (e == NULL) break;
@@ -120,14 +186,13 @@ const char *luaO_pushvfstring (lua_State *L, const char *fmt, va_list argp) {
       case 's': {
         const char *s = va_arg(argp, char *);
         if (s == NULL) s = "(null)";
-        pushstr(L, s);
+        pushstr(L, s, strlen(s));
         break;
       }
       case 'c': {
-        char buff[2];
-        buff[0] = cast(char, va_arg(argp, int));
-        buff[1] = '\0';
-        pushstr(L, buff);
+        char buff;
+        buff = cast(char, va_arg(argp, int));
+        pushstr(L, &buff, 1);
         break;
       }
       case 'd': {
@@ -142,29 +207,26 @@ const char *luaO_pushvfstring (lua_State *L, const char *fmt, va_list argp) {
       }
       case 'p': {
         char buff[4*sizeof(void *) + 8]; /* should be enough space for a `%p' */
-        sprintf(buff, "%p", va_arg(argp, void *));
-        pushstr(L, buff);
+        int l = sprintf(buff, "%p", va_arg(argp, void *));
+        pushstr(L, buff, l);
         break;
       }
       case '%': {
-        pushstr(L, "%");
+        pushstr(L, "%", 1);
         break;
       }
       default: {
-        char buff[3];
-        buff[0] = '%';
-        buff[1] = *(e+1);
-        buff[2] = '\0';
-        pushstr(L, buff);
+        luaG_runerror(L,
+            "invalid option " LUA_QL("%%%c") " to " LUA_QL("lua_pushfstring"),
+            *(e + 1));
         break;
       }
     }
     n += 2;
     fmt = e+2;
   }
-  pushstr(L, fmt);
-  luaV_concat(L, n+1, cast_int(L->top - L->base) - 1);
-  L->top -= n;
+  pushstr(L, fmt, strlen(fmt));
+  if (n > 0) luaV_concat(L, n + 1);
   return svalue(L->top - 1);
 }
 
@@ -179,36 +241,48 @@ const char *luaO_pushfstring (lua_State *L, const char *fmt, ...) {
 }
 
 
+/* number of chars of a literal string without the ending \0 */
+#define LL(x)	(sizeof(x)/sizeof(char) - 1)
+
+#define RETS	"..."
+#define PRE	"[string \""
+#define POS	"\"]"
+
+#define addstr(a,b,l)	( memcpy(a,b,(l) * sizeof(char)), a += (l) )
+
 void luaO_chunkid (char *out, const char *source, size_t bufflen) {
-  if (*source == '=') {
-    strncpy(out, source+1, bufflen);  /* remove first char */
-    out[bufflen-1] = '\0';  /* ensures null termination */
+  size_t l = strlen(source);
+  if (*source == '=') {  /* 'literal' source */
+    if (l <= bufflen)  /* small enough? */
+      memcpy(out, source + 1, l * sizeof(char));
+    else {  /* truncate it */
+      addstr(out, source + 1, bufflen - 1);
+      *out = '\0';
+    }
   }
-  else {  /* out = "source", or "...source" */
-    if (*source == '@') {
-      size_t l;
-      source++;  /* skip the `@' */
-      bufflen -= sizeof(" '...' ");
-      l = strlen(source);
-      strcpy(out, "");
-      if (l > bufflen) {
-        source += (l-bufflen);  /* get last part of file name */
-        strcat(out, "...");
-      }
-      strcat(out, source);
+  else if (*source == '@') {  /* file name */
+    if (l <= bufflen)  /* small enough? */
+      memcpy(out, source + 1, l * sizeof(char));
+    else {  /* add '...' before rest of name */
+      addstr(out, RETS, LL(RETS));
+      bufflen -= LL(RETS);
+      memcpy(out, source + 1 + l - bufflen, bufflen * sizeof(char));
     }
-    else {  /* out = [string "string"] */
-      size_t len = strcspn(source, "\n\r");  /* stop at first newline */
-      bufflen -= sizeof(" [string \"...\"] ");
-      if (len > bufflen) len = bufflen;
-      strcpy(out, "[string \"");
-      if (source[len] != '\0') {  /* must truncate? */
-        strncat(out, source, len);
-        strcat(out, "...");
-      }
-      else
-        strcat(out, source);
-      strcat(out, "\"]");
+  }
+  else {  /* string; format as [string "source"] */
+    const char *nl = strchr(source, '\n');  /* find first new line (if any) */
+    addstr(out, PRE, LL(PRE));  /* add prefix */
+    bufflen -= LL(PRE RETS POS) + 1;  /* save space for prefix+suffix+'\0' */
+    if (l < bufflen && nl == NULL) {  /* small one-line source? */
+      addstr(out, source, l);  /* keep it */
+    }
+    else {
+      if (nl != NULL) l = nl - source;  /* stop at first newline */
+      if (l > bufflen) l = bufflen;
+      addstr(out, source, l);
+      addstr(out, RETS, LL(RETS));
     }
+    memcpy(out, POS, (LL(POS) + 1) * sizeof(char));
   }
 }
+
diff --git a/src/lobject.h b/src/lobject.h
index f1e447e..d69d615 100644..100755
--- a/src/lobject.h
+++ b/src/lobject.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lobject.h,v 2.20.1.2 2008/08/06 13:29:48 roberto Exp $
+** $Id: lobject.h,v 2.61 2011/07/04 20:29:02 roberto Exp $
 ** Type definitions for Lua objects
 ** See Copyright Notice in lua.h
 */
@@ -16,18 +16,44 @@
 #include "lua.h"
 
 
-/* tags for values visible from Lua */
-#define LAST_TAG	LUA_TTHREAD
+/*
+** Extra tags for non-values
+*/
+#define LUA_TPROTO	LUA_NUMTAGS
+#define LUA_TUPVAL	(LUA_NUMTAGS+1)
+#define LUA_TDEADKEY	(LUA_NUMTAGS+2)
 
-#define NUM_TAGS	(LAST_TAG+1)
+/*
+** number of all possible tags (including LUA_TNONE but excluding DEADKEY)
+*/
+#define LUA_TOTALTAGS	(LUA_TUPVAL+2)
 
 
 /*
-** Extra tags for non-values
+** tags for Tagged Values have the following use of bits:
+** bits 0-3: actual tag (a LUA_T* value)
+** bits 4-5: variant bits
+** bit 6: whether value is collectable
+*/
+
+/*
+** LUA_TFUNCTION variants:
+** 0 - Lua function
+** 1 - light C function
+** 2 - regular C function (closure)
 */
-#define LUA_TPROTO	(LAST_TAG+1)
-#define LUA_TUPVAL	(LAST_TAG+2)
-#define LUA_TDEADKEY	(LAST_TAG+3)
+
+/* Variant tags for functions */
+#define LUA_TLCL	(LUA_TFUNCTION | (0 << 4))  /* Lua closure */
+#define LUA_TLCF	(LUA_TFUNCTION | (1 << 4))  /* light C function */
+#define LUA_TCCL	(LUA_TFUNCTION | (2 << 4))  /* C closure */
+
+
+/* Bit mark for collectable types */
+#define BIT_ISCOLLECTABLE	(1 << 6)
+
+/* mark a tag as collectable */
+#define ctb(t)			((t) | BIT_ISCOLLECTABLE)
 
 
 /*
@@ -52,120 +78,164 @@ typedef struct GCheader {
 
 
 
-
 /*
 ** Union of all Lua values
 */
-typedef union {
-  GCObject *gc;
-  void *p;
-  lua_Number n;
-  int b;
-} Value;
+typedef union Value Value;
+
+
+#define numfield	lua_Number n;    /* numbers */
+
 
 
 /*
-** Tagged Values
+** Tagged Values. This is the basic representation of values in Lua,
+** an actual value plus a tag with its type.
 */
 
-#define TValuefields	Value value; int tt
+#define TValuefields	Value value_; int tt_
+
+typedef struct lua_TValue TValue;
+
+
+/* macro defining a nil value */
+#define NILCONSTANT	{NULL}, LUA_TNIL
 
-typedef struct lua_TValue {
-  TValuefields;
-} TValue;
+
+#define val_(o)		((o)->value_)
+#define num_(o)		(val_(o).n)
+
+
+/* raw type tag of a TValue */
+#define rttype(o)	((o)->tt_)
+
+/* type tag of a TValue (bits 0-3 for tags + variant bits 4-5) */
+#define ttype(o)	(rttype(o) & 0x3F)
+
+
+/* type tag of a TValue with no variants (bits 0-3) */
+#define ttypenv(o)	(rttype(o) & 0x0F)
 
 
 /* Macros to test type */
-#define ttisnil(o)	(ttype(o) == LUA_TNIL)
-#define ttisnumber(o)	(ttype(o) == LUA_TNUMBER)
-#define ttisstring(o)	(ttype(o) == LUA_TSTRING)
-#define ttistable(o)	(ttype(o) == LUA_TTABLE)
-#define ttisfunction(o)	(ttype(o) == LUA_TFUNCTION)
-#define ttisboolean(o)	(ttype(o) == LUA_TBOOLEAN)
-#define ttisuserdata(o)	(ttype(o) == LUA_TUSERDATA)
-#define ttisthread(o)	(ttype(o) == LUA_TTHREAD)
-#define ttislightuserdata(o)	(ttype(o) == LUA_TLIGHTUSERDATA)
+#define checktag(o,t)		(rttype(o) == (t))
+#define ttisnumber(o)		checktag((o), LUA_TNUMBER)
+#define ttisnil(o)		checktag((o), LUA_TNIL)
+#define ttisboolean(o)		checktag((o), LUA_TBOOLEAN)
+#define ttislightuserdata(o)	checktag((o), LUA_TLIGHTUSERDATA)
+#define ttisstring(o)		checktag((o), ctb(LUA_TSTRING))
+#define ttistable(o)		checktag((o), ctb(LUA_TTABLE))
+#define ttisfunction(o)		(ttypenv(o) == LUA_TFUNCTION)
+#define ttisclosure(o)		((rttype(o) & 0x1F) == LUA_TFUNCTION)
+#define ttisCclosure(o)		checktag((o), ctb(LUA_TCCL))
+#define ttisLclosure(o)		checktag((o), ctb(LUA_TLCL))
+#define ttislcf(o)		checktag((o), LUA_TLCF)
+#define ttisuserdata(o)		checktag((o), ctb(LUA_TUSERDATA))
+#define ttisthread(o)		checktag((o), ctb(LUA_TTHREAD))
+#define ttisdeadkey(o)		checktag((o), ctb(LUA_TDEADKEY))
+
+#define ttisequal(o1,o2)	(rttype(o1) == rttype(o2))
 
 /* Macros to access values */
-#define ttype(o)	((o)->tt)
-#define gcvalue(o)	check_exp(iscollectable(o), (o)->value.gc)
-#define pvalue(o)	check_exp(ttislightuserdata(o), (o)->value.p)
-#define nvalue(o)	check_exp(ttisnumber(o), (o)->value.n)
-#define rawtsvalue(o)	check_exp(ttisstring(o), &(o)->value.gc->ts)
+#define nvalue(o)	check_exp(ttisnumber(o), num_(o))
+#define gcvalue(o)	check_exp(iscollectable(o), val_(o).gc)
+#define pvalue(o)	check_exp(ttislightuserdata(o), val_(o).p)
+#define rawtsvalue(o)	check_exp(ttisstring(o), &val_(o).gc->ts)
 #define tsvalue(o)	(&rawtsvalue(o)->tsv)
-#define rawuvalue(o)	check_exp(ttisuserdata(o), &(o)->value.gc->u)
+#define rawuvalue(o)	check_exp(ttisuserdata(o), &val_(o).gc->u)
 #define uvalue(o)	(&rawuvalue(o)->uv)
-#define clvalue(o)	check_exp(ttisfunction(o), &(o)->value.gc->cl)
-#define hvalue(o)	check_exp(ttistable(o), &(o)->value.gc->h)
-#define bvalue(o)	check_exp(ttisboolean(o), (o)->value.b)
-#define thvalue(o)	check_exp(ttisthread(o), &(o)->value.gc->th)
+#define clvalue(o)	check_exp(ttisclosure(o), &val_(o).gc->cl)
+#define clLvalue(o)	check_exp(ttisLclosure(o), &val_(o).gc->cl.l)
+#define clCvalue(o)	check_exp(ttisCclosure(o), &val_(o).gc->cl.c)
+#define fvalue(o)	check_exp(ttislcf(o), val_(o).f)
+#define hvalue(o)	check_exp(ttistable(o), &val_(o).gc->h)
+#define bvalue(o)	check_exp(ttisboolean(o), val_(o).b)
+#define thvalue(o)	check_exp(ttisthread(o), &val_(o).gc->th)
 
 #define l_isfalse(o)	(ttisnil(o) || (ttisboolean(o) && bvalue(o) == 0))
 
-/*
-** for internal debug only
-*/
-#define checkconsistency(obj) \
-  lua_assert(!iscollectable(obj) || (ttype(obj) == (obj)->value.gc->gch.tt))
+
+#define iscollectable(o)	(rttype(o) & BIT_ISCOLLECTABLE)
+
+
+/* Macros for internal tests */
+#define righttt(obj)		(ttypenv(obj) == gcvalue(obj)->gch.tt)
 
 #define checkliveness(g,obj) \
-  lua_assert(!iscollectable(obj) || \
-  ((ttype(obj) == (obj)->value.gc->gch.tt) && !isdead(g, (obj)->value.gc)))
+	lua_longassert(!iscollectable(obj) || \
+			(righttt(obj) && !isdead(g,gcvalue(obj))))
 
 
 /* Macros to set values */
-#define setnilvalue(obj) ((obj)->tt=LUA_TNIL)
+#define settt_(o,t)	((o)->tt_=(t))
 
 #define setnvalue(obj,x) \
-  { TValue *i_o=(obj); i_o->value.n=(x); i_o->tt=LUA_TNUMBER; }
+  { TValue *io=(obj); num_(io)=(x); settt_(io, LUA_TNUMBER); }
+
+#define changenvalue(o,x)	check_exp(ttisnumber(o), num_(o)=(x))
+
+#define setnilvalue(obj) settt_(obj, LUA_TNIL)
+
+#define setfvalue(obj,x) \
+  { TValue *io=(obj); val_(io).f=(x); settt_(io, LUA_TLCF); }
 
 #define setpvalue(obj,x) \
-  { TValue *i_o=(obj); i_o->value.p=(x); i_o->tt=LUA_TLIGHTUSERDATA; }
+  { TValue *io=(obj); val_(io).p=(x); settt_(io, LUA_TLIGHTUSERDATA); }
 
 #define setbvalue(obj,x) \
-  { TValue *i_o=(obj); i_o->value.b=(x); i_o->tt=LUA_TBOOLEAN; }
+  { TValue *io=(obj); val_(io).b=(x); settt_(io, LUA_TBOOLEAN); }
+
+#define setgcovalue(L,obj,x) \
+  { TValue *io=(obj); GCObject *i_g=(x); \
+    val_(io).gc=i_g; settt_(io, ctb(gch(i_g)->tt)); }
 
 #define setsvalue(L,obj,x) \
-  { TValue *i_o=(obj); \
-    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TSTRING; \
-    checkliveness(G(L),i_o); }
+  { TValue *io=(obj); \
+    val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TSTRING)); \
+    checkliveness(G(L),io); }
 
 #define setuvalue(L,obj,x) \
-  { TValue *i_o=(obj); \
-    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TUSERDATA; \
-    checkliveness(G(L),i_o); }
+  { TValue *io=(obj); \
+    val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TUSERDATA)); \
+    checkliveness(G(L),io); }
 
 #define setthvalue(L,obj,x) \
-  { TValue *i_o=(obj); \
-    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TTHREAD; \
-    checkliveness(G(L),i_o); }
+  { TValue *io=(obj); \
+    val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TTHREAD)); \
+    checkliveness(G(L),io); }
+
+#define setclLvalue(L,obj,x) \
+  { TValue *io=(obj); \
+    val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TLCL)); \
+    checkliveness(G(L),io); }
 
-#define setclvalue(L,obj,x) \
-  { TValue *i_o=(obj); \
-    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TFUNCTION; \
-    checkliveness(G(L),i_o); }
+#define setclCvalue(L,obj,x) \
+  { TValue *io=(obj); \
+    val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TCCL)); \
+    checkliveness(G(L),io); }
 
 #define sethvalue(L,obj,x) \
-  { TValue *i_o=(obj); \
-    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TTABLE; \
-    checkliveness(G(L),i_o); }
+  { TValue *io=(obj); \
+    val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TTABLE)); \
+    checkliveness(G(L),io); }
 
 #define setptvalue(L,obj,x) \
-  { TValue *i_o=(obj); \
-    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TPROTO; \
-    checkliveness(G(L),i_o); }
+  { TValue *io=(obj); \
+    val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TPROTO)); \
+    checkliveness(G(L),io); }
 
+#define setdeadvalue(obj)	settt_(obj, ctb(LUA_TDEADKEY))
 
 
 
 #define setobj(L,obj1,obj2) \
-  { const TValue *o2=(obj2); TValue *o1=(obj1); \
-    o1->value = o2->value; o1->tt=o2->tt; \
-    checkliveness(G(L),o1); }
+	{ const TValue *io2=(obj2); TValue *io1=(obj1); \
+	  io1->value_ = io2->value_; io1->tt_ = io2->tt_; \
+	  checkliveness(G(L),io1); }
 
 
 /*
-** different types of sets, according to destination
+** different types of assignments, according to destination
 */
 
 /* from stack to (same) stack */
@@ -183,18 +253,125 @@ typedef struct lua_TValue {
 #define setobj2n	setobj
 #define setsvalue2n	setsvalue
 
-#define setttype(obj, tt) (ttype(obj) = (tt))
 
 
-#define iscollectable(o)	(ttype(o) >= LUA_TSTRING)
 
+/*
+** {======================================================
+** NaN Trick
+** =======================================================
+*/
+
+#if defined(LUA_NANTRICKLE) || defined(LUA_NANTRICKBE)
+
+/*
+** numbers are represented in the 'd_' field. All other values have the
+** value (NNMARK | tag) in 'tt_'. A number with such pattern would be
+** a "signaled NaN", which is never generated by regular operations by
+** the CPU (nor by 'strtod')
+*/
+#if !defined(NNMARK)
+#define NNMARK		0x7FF7A500
+#endif
+
+#undef TValuefields
+#undef NILCONSTANT
+#if defined(LUA_NANTRICKLE)
+/* little endian */
+#define TValuefields  \
+	union { struct { Value v_; int tt_; } i; double d_; } u
+#define NILCONSTANT	{{{NULL}, tag2tt(LUA_TNIL)}}
+#else
+/* big endian */
+#define TValuefields  \
+	union { struct { int tt_; Value v_; } i; double d_; } u
+#define NILCONSTANT	{{tag2tt(LUA_TNIL), {NULL}}}
+#endif
+
+#undef numfield
+#define numfield	/* no such field; numbers are the entire struct */
+
+/* basic check to distinguish numbers from non-numbers */
+#undef ttisnumber
+#define ttisnumber(o)	(((o)->u.i.tt_ & 0x7fffff00) != NNMARK)
+
+#define tag2tt(t)	(NNMARK | (t))
+
+#undef val_
+#define val_(o)		((o)->u.i.v_)
+#undef num_
+#define num_(o)		((o)->u.d_)
+
+#undef rttype
+#define rttype(o)	(ttisnumber(o) ? LUA_TNUMBER : (o)->u.i.tt_ & 0xff)
+
+#undef settt_
+#define settt_(o,t)	((o)->u.i.tt_=tag2tt(t))
+
+#undef setnvalue
+#define setnvalue(obj,x) \
+	{ TValue *io_=(obj); num_(io_)=(x); lua_assert(ttisnumber(io_)); }
+
+#undef setobj
+#define setobj(L,obj1,obj2) \
+	{ const TValue *o2_=(obj2); TValue *o1_=(obj1); \
+	  o1_->u = o2_->u; \
+	  checkliveness(G(L),o1_); }
+
+
+/*
+** these redefinitions are not mandatory, but these forms are more efficient
+*/
+
+#undef checktag
+#define checktag(o,t)	((o)->u.i.tt_ == tag2tt(t))
+
+#undef ttisequal
+#define ttisequal(o1,o2)  \
+	(ttisnumber(o1) ? ttisnumber(o2) : ((o1)->u.i.tt_ == (o2)->u.i.tt_))
+
+
+
+#define luai_checknum(L,o,c)	{ if (!ttisnumber(o)) c; }
+
+
+#else
+
+#define luai_checknum(L,o,c)	{ /* empty */ }
+
+#endif
+/* }====================================================== */
+
+
+
+/*
+** {======================================================
+** types and prototypes
+** =======================================================
+*/
+
+
+union Value {
+  GCObject *gc;    /* collectable objects */
+  void *p;         /* light userdata */
+  int b;           /* booleans */
+  lua_CFunction f; /* light C functions */
+  numfield         /* numbers */
+};
+
+
+struct lua_TValue {
+  TValuefields;
+};
 
 
 typedef TValue *StkId;  /* index to stack elements */
 
 
+
+
 /*
-** String headers for string table
+** Header for string value; string bytes follow the end of this structure
 */
 typedef union TString {
   L_Umaxalign dummy;  /* ensures maximum alignment for strings */
@@ -202,28 +379,53 @@ typedef union TString {
     CommonHeader;
     lu_byte reserved;
     unsigned int hash;
-    size_t len;
+    size_t len;  /* number of characters in string */
   } tsv;
 } TString;
 
 
+/* get the actual string (array of bytes) from a TString */
 #define getstr(ts)	cast(const char *, (ts) + 1)
-#define svalue(o)       getstr(rawtsvalue(o))
 
+/* get the actual string (array of bytes) from a Lua value */
+#define svalue(o)       getstr(rawtsvalue(o))
 
 
+/*
+** Header for userdata; memory area follows the end of this structure
+*/
 typedef union Udata {
   L_Umaxalign dummy;  /* ensures maximum alignment for `local' udata */
   struct {
     CommonHeader;
     struct Table *metatable;
     struct Table *env;
-    size_t len;
+    size_t len;  /* number of bytes */
   } uv;
 } Udata;
 
 
 
+/*
+** Description of an upvalue for function prototypes
+*/
+typedef struct Upvaldesc {
+  TString *name;  /* upvalue name (for debug information) */
+  lu_byte instack;  /* whether it is in stack */
+  lu_byte idx;  /* index of upvalue (in stack or in outer function's list) */
+} Upvaldesc;
+
+
+/*
+** Description of a local variable for function prototypes
+** (used for debug information)
+*/
+typedef struct LocVar {
+  TString *varname;
+  int startpc;  /* first point where variable is active */
+  int endpc;    /* first point where variable is dead */
+} LocVar;
+
 
 /*
 ** Function Prototypes
@@ -234,10 +436,11 @@ typedef struct Proto {
   Instruction *code;
   struct Proto **p;  /* functions defined inside the function */
   int *lineinfo;  /* map from opcodes to source lines */
-  struct LocVar *locvars;  /* information about local variables */
-  TString **upvalues;  /* upvalue names */
+  LocVar *locvars;  /* information about local variables */
+  Upvaldesc *upvalues;  /* upvalue information */
+  union Closure *cache;  /* last created closure with this prototype */
   TString  *source;
-  int sizeupvalues;
+  int sizeupvalues;  /* size of 'upvalues' */
   int sizek;  /* size of `k' */
   int sizecode;
   int sizelineinfo;
@@ -246,31 +449,16 @@ typedef struct Proto {
   int linedefined;
   int lastlinedefined;
   GCObject *gclist;
-  lu_byte nups;  /* number of upvalues */
-  lu_byte numparams;
+  lu_byte numparams;  /* number of fixed parameters */
   lu_byte is_vararg;
-  lu_byte maxstacksize;
+  lu_byte maxstacksize;  /* maximum stack used by this function */
 } Proto;
 
 
-/* masks for new-style vararg */
-#define VARARG_HASARG		1
-#define VARARG_ISVARARG		2
-#define VARARG_NEEDSARG		4
-
-
-typedef struct LocVar {
-  TString *varname;
-  int startpc;  /* first point where variable is active */
-  int endpc;    /* first point where variable is dead */
-} LocVar;
-
-
 
 /*
-** Upvalues
+** Lua Upvalues
 */
-
 typedef struct UpVal {
   CommonHeader;
   TValue *v;  /* points to stack or to its own value */
@@ -289,20 +477,19 @@ typedef struct UpVal {
 */
 
 #define ClosureHeader \
-	CommonHeader; lu_byte isC; lu_byte nupvalues; GCObject *gclist; \
-	struct Table *env
+	CommonHeader; lu_byte isC; lu_byte nupvalues; GCObject *gclist
 
 typedef struct CClosure {
   ClosureHeader;
   lua_CFunction f;
-  TValue upvalue[1];
+  TValue upvalue[1];  /* list of upvalues */
 } CClosure;
 
 
 typedef struct LClosure {
   ClosureHeader;
   struct Proto *p;
-  UpVal *upvals[1];
+  UpVal *upvals[1];  /* list of upvalues */
 } LClosure;
 
 
@@ -312,8 +499,9 @@ typedef union Closure {
 } Closure;
 
 
-#define iscfunction(o)	(ttype(o) == LUA_TFUNCTION && clvalue(o)->c.isC)
-#define isLfunction(o)	(ttype(o) == LUA_TFUNCTION && !clvalue(o)->c.isC)
+#define isLfunction(o)	ttisLclosure(o)
+
+#define getproto(o)	(clLvalue(o)->p)
 
 
 /*
@@ -337,7 +525,7 @@ typedef struct Node {
 
 typedef struct Table {
   CommonHeader;
-  lu_byte flags;  /* 1<<p means tagmethod(p) is not present */ 
+  lu_byte flags;  /* 1<<p means tagmethod(p) is not present */
   lu_byte lsizenode;  /* log2 of size of `node' array */
   struct Table *metatable;
   TValue *array;  /* array part */
@@ -360,17 +548,21 @@ typedef struct Table {
 #define sizenode(t)	(twoto((t)->lsizenode))
 
 
+/*
+** (address of) a fixed nil value
+*/
 #define luaO_nilobject		(&luaO_nilobject_)
 
-LUAI_DATA const TValue luaO_nilobject_;
 
-#define ceillog2(x)	(luaO_log2((x)-1) + 1)
+LUAI_DDEC const TValue luaO_nilobject_;
+
 
-LUAI_FUNC int luaO_log2 (unsigned int x);
 LUAI_FUNC int luaO_int2fb (unsigned int x);
 LUAI_FUNC int luaO_fb2int (int x);
-LUAI_FUNC int luaO_rawequalObj (const TValue *t1, const TValue *t2);
-LUAI_FUNC int luaO_str2d (const char *s, lua_Number *result);
+LUAI_FUNC int luaO_ceillog2 (unsigned int x);
+LUAI_FUNC lua_Number luaO_arith (int op, lua_Number v1, lua_Number v2);
+LUAI_FUNC int luaO_str2d (const char *s, size_t len, lua_Number *result);
+LUAI_FUNC int luaO_hexavalue (int c);
 LUAI_FUNC const char *luaO_pushvfstring (lua_State *L, const char *fmt,
                                                        va_list argp);
 LUAI_FUNC const char *luaO_pushfstring (lua_State *L, const char *fmt, ...);
diff --git a/src/lopcodes.c b/src/lopcodes.c
index 4cc7452..2e34676 100644..100755
--- a/src/lopcodes.c
+++ b/src/lopcodes.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lopcodes.c,v 1.37.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lopcodes.c,v 1.48 2011/04/19 16:22:13 roberto Exp $
 ** See Copyright Notice in lua.h
 */
 
@@ -13,15 +13,16 @@
 
 /* ORDER OP */
 
-const char *const luaP_opnames[NUM_OPCODES+1] = {
+LUAI_DDEF const char *const luaP_opnames[NUM_OPCODES+1] = {
   "MOVE",
   "LOADK",
+  "LOADKX",
   "LOADBOOL",
   "LOADNIL",
   "GETUPVAL",
-  "GETGLOBAL",
+  "GETTABUP",
   "GETTABLE",
-  "SETGLOBAL",
+  "SETTABUP",
   "SETUPVAL",
   "SETTABLE",
   "NEWTABLE",
@@ -47,27 +48,29 @@ const char *const luaP_opnames[NUM_OPCODES+1] = {
   "RETURN",
   "FORLOOP",
   "FORPREP",
+  "TFORCALL",
   "TFORLOOP",
   "SETLIST",
-  "CLOSE",
   "CLOSURE",
   "VARARG",
+  "EXTRAARG",
   NULL
 };
 
 
 #define opmode(t,a,b,c,m) (((t)<<7) | ((a)<<6) | ((b)<<4) | ((c)<<2) | (m))
 
-const lu_byte luaP_opmodes[NUM_OPCODES] = {
+LUAI_DDEF const lu_byte luaP_opmodes[NUM_OPCODES] = {
 /*       T  A    B       C     mode		   opcode	*/
-  opmode(0, 1, OpArgR, OpArgN, iABC) 		/* OP_MOVE */
+  opmode(0, 1, OpArgR, OpArgN, iABC)		/* OP_MOVE */
  ,opmode(0, 1, OpArgK, OpArgN, iABx)		/* OP_LOADK */
+ ,opmode(0, 1, OpArgN, OpArgN, iABx)		/* OP_LOADKX */
  ,opmode(0, 1, OpArgU, OpArgU, iABC)		/* OP_LOADBOOL */
- ,opmode(0, 1, OpArgR, OpArgN, iABC)		/* OP_LOADNIL */
+ ,opmode(0, 1, OpArgU, OpArgN, iABC)		/* OP_LOADNIL */
  ,opmode(0, 1, OpArgU, OpArgN, iABC)		/* OP_GETUPVAL */
- ,opmode(0, 1, OpArgK, OpArgN, iABx)		/* OP_GETGLOBAL */
+ ,opmode(0, 1, OpArgU, OpArgK, iABC)		/* OP_GETTABUP */
  ,opmode(0, 1, OpArgR, OpArgK, iABC)		/* OP_GETTABLE */
- ,opmode(0, 0, OpArgK, OpArgN, iABx)		/* OP_SETGLOBAL */
+ ,opmode(0, 0, OpArgK, OpArgK, iABC)		/* OP_SETTABUP */
  ,opmode(0, 0, OpArgU, OpArgN, iABC)		/* OP_SETUPVAL */
  ,opmode(0, 0, OpArgK, OpArgK, iABC)		/* OP_SETTABLE */
  ,opmode(0, 1, OpArgU, OpArgU, iABC)		/* OP_NEWTABLE */
@@ -86,17 +89,18 @@ const lu_byte luaP_opmodes[NUM_OPCODES] = {
  ,opmode(1, 0, OpArgK, OpArgK, iABC)		/* OP_EQ */
  ,opmode(1, 0, OpArgK, OpArgK, iABC)		/* OP_LT */
  ,opmode(1, 0, OpArgK, OpArgK, iABC)		/* OP_LE */
- ,opmode(1, 1, OpArgR, OpArgU, iABC)		/* OP_TEST */
+ ,opmode(1, 0, OpArgN, OpArgU, iABC)		/* OP_TEST */
  ,opmode(1, 1, OpArgR, OpArgU, iABC)		/* OP_TESTSET */
  ,opmode(0, 1, OpArgU, OpArgU, iABC)		/* OP_CALL */
  ,opmode(0, 1, OpArgU, OpArgU, iABC)		/* OP_TAILCALL */
  ,opmode(0, 0, OpArgU, OpArgN, iABC)		/* OP_RETURN */
  ,opmode(0, 1, OpArgR, OpArgN, iAsBx)		/* OP_FORLOOP */
  ,opmode(0, 1, OpArgR, OpArgN, iAsBx)		/* OP_FORPREP */
- ,opmode(1, 0, OpArgN, OpArgU, iABC)		/* OP_TFORLOOP */
+ ,opmode(0, 0, OpArgN, OpArgU, iABC)		/* OP_TFORCALL */
+ ,opmode(0, 1, OpArgR, OpArgN, iAsBx)		/* OP_TFORLOOP */
  ,opmode(0, 0, OpArgU, OpArgU, iABC)		/* OP_SETLIST */
- ,opmode(0, 0, OpArgN, OpArgN, iABC)		/* OP_CLOSE */
  ,opmode(0, 1, OpArgU, OpArgN, iABx)		/* OP_CLOSURE */
  ,opmode(0, 1, OpArgU, OpArgN, iABC)		/* OP_VARARG */
+ ,opmode(0, 0, OpArgU, OpArgU, iAx)		/* OP_EXTRAARG */
 };
 
diff --git a/src/lopcodes.h b/src/lopcodes.h
index 41224d6..01c69bd 100644..100755
--- a/src/lopcodes.h
+++ b/src/lopcodes.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lopcodes.h,v 1.125.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lopcodes.h,v 1.141 2011/04/19 16:22:13 roberto Exp $
 ** Opcodes for Lua virtual machine
 ** See Copyright Notice in lua.h
 */
@@ -17,6 +17,7 @@
 	`A' : 8 bits
 	`B' : 9 bits
 	`C' : 9 bits
+	'Ax' : 26 bits ('A', 'B', and 'C' together)
 	`Bx' : 18 bits (`B' and `C' together)
 	`sBx' : signed Bx
 
@@ -28,7 +29,7 @@
 ===========================================================================*/
 
 
-enum OpMode {iABC, iABx, iAsBx};  /* basic instruction format */
+enum OpMode {iABC, iABx, iAsBx, iAx};  /* basic instruction format */
 
 
 /*
@@ -38,6 +39,7 @@ enum OpMode {iABC, iABx, iAsBx};  /* basic instruction format */
 #define SIZE_B		9
 #define SIZE_Bx		(SIZE_C + SIZE_B)
 #define SIZE_A		8
+#define SIZE_Ax		(SIZE_C + SIZE_B + SIZE_A)
 
 #define SIZE_OP		6
 
@@ -46,6 +48,7 @@ enum OpMode {iABC, iABx, iAsBx};  /* basic instruction format */
 #define POS_C		(POS_A + SIZE_A)
 #define POS_B		(POS_C + SIZE_C)
 #define POS_Bx		POS_C
+#define POS_Ax		POS_A
 
 
 /*
@@ -61,6 +64,12 @@ enum OpMode {iABC, iABx, iAsBx};  /* basic instruction format */
 #define MAXARG_sBx        MAX_INT
 #endif
 
+#if SIZE_Ax < LUAI_BITSINT-1
+#define MAXARG_Ax	((1<<SIZE_Ax)-1)
+#else
+#define MAXARG_Ax	MAX_INT
+#endif
+
 
 #define MAXARG_A        ((1<<SIZE_A)-1)
 #define MAXARG_B        ((1<<SIZE_B)-1)
@@ -68,7 +77,7 @@ enum OpMode {iABC, iABx, iAsBx};  /* basic instruction format */
 
 
 /* creates a mask with `n' 1 bits at position `p' */
-#define MASK1(n,p)	((~((~(Instruction)0)<<n))<<p)
+#define MASK1(n,p)	((~((~(Instruction)0)<<(n)))<<(p))
 
 /* creates a mask with `n' 0 bits at position `p' */
 #define MASK0(n,p)	(~MASK1(n,p))
@@ -81,21 +90,24 @@ enum OpMode {iABC, iABx, iAsBx};  /* basic instruction format */
 #define SET_OPCODE(i,o)	((i) = (((i)&MASK0(SIZE_OP,POS_OP)) | \
 		((cast(Instruction, o)<<POS_OP)&MASK1(SIZE_OP,POS_OP))))
 
-#define GETARG_A(i)	(cast(int, ((i)>>POS_A) & MASK1(SIZE_A,0)))
-#define SETARG_A(i,u)	((i) = (((i)&MASK0(SIZE_A,POS_A)) | \
-		((cast(Instruction, u)<<POS_A)&MASK1(SIZE_A,POS_A))))
+#define getarg(i,pos,size)	(cast(int, ((i)>>pos) & MASK1(size,0)))
+#define setarg(i,v,pos,size)	((i) = (((i)&MASK0(size,pos)) | \
+                ((cast(Instruction, v)<<pos)&MASK1(size,pos))))
 
-#define GETARG_B(i)	(cast(int, ((i)>>POS_B) & MASK1(SIZE_B,0)))
-#define SETARG_B(i,b)	((i) = (((i)&MASK0(SIZE_B,POS_B)) | \
-		((cast(Instruction, b)<<POS_B)&MASK1(SIZE_B,POS_B))))
+#define GETARG_A(i)	getarg(i, POS_A, SIZE_A)
+#define SETARG_A(i,v)	setarg(i, v, POS_A, SIZE_A)
 
-#define GETARG_C(i)	(cast(int, ((i)>>POS_C) & MASK1(SIZE_C,0)))
-#define SETARG_C(i,b)	((i) = (((i)&MASK0(SIZE_C,POS_C)) | \
-		((cast(Instruction, b)<<POS_C)&MASK1(SIZE_C,POS_C))))
+#define GETARG_B(i)	getarg(i, POS_B, SIZE_B)
+#define SETARG_B(i,v)	setarg(i, v, POS_B, SIZE_B)
 
-#define GETARG_Bx(i)	(cast(int, ((i)>>POS_Bx) & MASK1(SIZE_Bx,0)))
-#define SETARG_Bx(i,b)	((i) = (((i)&MASK0(SIZE_Bx,POS_Bx)) | \
-		((cast(Instruction, b)<<POS_Bx)&MASK1(SIZE_Bx,POS_Bx))))
+#define GETARG_C(i)	getarg(i, POS_C, SIZE_C)
+#define SETARG_C(i,v)	setarg(i, v, POS_C, SIZE_C)
+
+#define GETARG_Bx(i)	getarg(i, POS_Bx, SIZE_Bx)
+#define SETARG_Bx(i,v)	setarg(i, v, POS_Bx, SIZE_Bx)
+
+#define GETARG_Ax(i)	getarg(i, POS_Ax, SIZE_Ax)
+#define SETARG_Ax(i,v)	setarg(i, v, POS_Ax, SIZE_Ax)
 
 #define GETARG_sBx(i)	(GETARG_Bx(i)-MAXARG_sBx)
 #define SETARG_sBx(i,b)	SETARG_Bx((i),cast(unsigned int, (b)+MAXARG_sBx))
@@ -110,6 +122,9 @@ enum OpMode {iABC, iABx, iAsBx};  /* basic instruction format */
 			| (cast(Instruction, a)<<POS_A) \
 			| (cast(Instruction, bc)<<POS_Bx))
 
+#define CREATE_Ax(o,a)		((cast(Instruction, o)<<POS_OP) \
+			| (cast(Instruction, a)<<POS_Ax))
+
 
 /*
 ** Macros to operate RK indices
@@ -153,14 +168,15 @@ name		args	description
 ------------------------------------------------------------------------*/
 OP_MOVE,/*	A B	R(A) := R(B)					*/
 OP_LOADK,/*	A Bx	R(A) := Kst(Bx)					*/
+OP_LOADKX,/*	A 	R(A) := Kst(extra arg)				*/
 OP_LOADBOOL,/*	A B C	R(A) := (Bool)B; if (C) pc++			*/
-OP_LOADNIL,/*	A B	R(A) := ... := R(B) := nil			*/
+OP_LOADNIL,/*	A B	R(A), R(A+1), ..., R(A+B) := nil		*/
 OP_GETUPVAL,/*	A B	R(A) := UpValue[B]				*/
 
-OP_GETGLOBAL,/*	A Bx	R(A) := Gbl[Kst(Bx)]				*/
+OP_GETTABUP,/*	A B C	R(A) := UpValue[B][RK(C)]			*/
 OP_GETTABLE,/*	A B C	R(A) := R(B)[RK(C)]				*/
 
-OP_SETGLOBAL,/*	A Bx	Gbl[Kst(Bx)] := R(A)				*/
+OP_SETTABUP,/*	A B C	UpValue[A][RK(B)] := RK(C)			*/
 OP_SETUPVAL,/*	A B	UpValue[B] := R(A)				*/
 OP_SETTABLE,/*	A B C	R(A)[RK(B)] := RK(C)				*/
 
@@ -180,14 +196,13 @@ OP_LEN,/*	A B	R(A) := length of R(B)				*/
 
 OP_CONCAT,/*	A B C	R(A) := R(B).. ... ..R(C)			*/
 
-OP_JMP,/*	sBx	pc+=sBx					*/
-
+OP_JMP,/*	A sBx	pc+=sBx; if (A) close all upvalues >= R(A) + 1	*/ 
 OP_EQ,/*	A B C	if ((RK(B) == RK(C)) ~= A) then pc++		*/
-OP_LT,/*	A B C	if ((RK(B) <  RK(C)) ~= A) then pc++  		*/
-OP_LE,/*	A B C	if ((RK(B) <= RK(C)) ~= A) then pc++  		*/
+OP_LT,/*	A B C	if ((RK(B) <  RK(C)) ~= A) then pc++		*/
+OP_LE,/*	A B C	if ((RK(B) <= RK(C)) ~= A) then pc++		*/
 
-OP_TEST,/*	A C	if not (R(A) <=> C) then pc++			*/ 
-OP_TESTSET,/*	A B C	if (R(B) <=> C) then R(A) := R(B) else pc++	*/ 
+OP_TEST,/*	A C	if not (R(A) <=> C) then pc++			*/
+OP_TESTSET,/*	A B C	if (R(B) <=> C) then R(A) := R(B) else pc++	*/
 
 OP_CALL,/*	A B C	R(A), ... ,R(A+C-2) := R(A)(R(A+1), ... ,R(A+B-1)) */
 OP_TAILCALL,/*	A B C	return R(A)(R(A+1), ... ,R(A+B-1))		*/
@@ -197,39 +212,44 @@ OP_FORLOOP,/*	A sBx	R(A)+=R(A+2);
 			if R(A) <?= R(A+1) then { pc+=sBx; R(A+3)=R(A) }*/
 OP_FORPREP,/*	A sBx	R(A)-=R(A+2); pc+=sBx				*/
 
-OP_TFORLOOP,/*	A C	R(A+3), ... ,R(A+2+C) := R(A)(R(A+1), R(A+2)); 
-                        if R(A+3) ~= nil then R(A+2)=R(A+3) else pc++	*/ 
+OP_TFORCALL,/*	A C	R(A+3), ... ,R(A+2+C) := R(A)(R(A+1), R(A+2));	*/
+OP_TFORLOOP,/*	A sBx	if R(A+1) ~= nil then { R(A)=R(A+1); pc += sBx }*/
+
 OP_SETLIST,/*	A B C	R(A)[(C-1)*FPF+i] := R(A+i), 1 <= i <= B	*/
 
-OP_CLOSE,/*	A 	close all variables in the stack up to (>=) R(A)*/
-OP_CLOSURE,/*	A Bx	R(A) := closure(KPROTO[Bx], R(A), ... ,R(A+n))	*/
+OP_CLOSURE,/*	A Bx	R(A) := closure(KPROTO[Bx])			*/
+
+OP_VARARG,/*	A B	R(A), R(A+1), ..., R(A+B-2) = vararg		*/
 
-OP_VARARG/*	A B	R(A), R(A+1), ..., R(A+B-1) = vararg		*/
+OP_EXTRAARG/*	Ax	extra (larger) argument for previous opcode	*/
 } OpCode;
 
 
-#define NUM_OPCODES	(cast(int, OP_VARARG) + 1)
+#define NUM_OPCODES	(cast(int, OP_EXTRAARG) + 1)
 
 
 
 /*===========================================================================
   Notes:
-  (*) In OP_CALL, if (B == 0) then B = top. C is the number of returns - 1,
-      and can be 0: OP_CALL then sets `top' to last_result+1, so
-      next open instruction (OP_CALL, OP_RETURN, OP_SETLIST) may use `top'.
+  (*) In OP_CALL, if (B == 0) then B = top. If (C == 0), then `top' is
+  set to last_result+1, so next open instruction (OP_CALL, OP_RETURN,
+  OP_SETLIST) may use `top'.
 
   (*) In OP_VARARG, if (B == 0) then use actual number of varargs and
-      set top (like in OP_CALL with C == 0).
+  set top (like in OP_CALL with C == 0).
 
-  (*) In OP_RETURN, if (B == 0) then return up to `top'
+  (*) In OP_RETURN, if (B == 0) then return up to `top'.
 
-  (*) In OP_SETLIST, if (B == 0) then B = `top';
-      if (C == 0) then next `instruction' is real C
+  (*) In OP_SETLIST, if (B == 0) then B = `top'; if (C == 0) then next
+  'instruction' is EXTRAARG(real C).
+
+  (*) In OP_LOADKX, the next 'instruction' is always EXTRAARG.
 
   (*) For comparisons, A specifies what condition the test should accept
-      (true or false).
+  (true or false).
+
+  (*) All `skips' (pc++) assume that next instruction is a jump.
 
-  (*) All `skips' (pc++) assume that next instruction is a jump
 ===========================================================================*/
 
 
@@ -239,8 +259,8 @@ OP_VARARG/*	A B	R(A), R(A+1), ..., R(A+B-1) = vararg		*/
 ** bits 2-3: C arg mode
 ** bits 4-5: B arg mode
 ** bit 6: instruction set register A
-** bit 7: operator is a test
-*/  
+** bit 7: operator is a test (next instruction must be a jump)
+*/
 
 enum OpArgMask {
   OpArgN,  /* argument is not used */
@@ -249,7 +269,7 @@ enum OpArgMask {
   OpArgK   /* argument is a constant or register/constant */
 };
 
-LUAI_DATA const lu_byte luaP_opmodes[NUM_OPCODES];
+LUAI_DDEC const lu_byte luaP_opmodes[NUM_OPCODES];
 
 #define getOpMode(m)	(cast(enum OpMode, luaP_opmodes[m] & 3))
 #define getBMode(m)	(cast(enum OpArgMask, (luaP_opmodes[m] >> 4) & 3))
@@ -258,7 +278,7 @@ LUAI_DATA const lu_byte luaP_opmodes[NUM_OPCODES];
 #define testTMode(m)	(luaP_opmodes[m] & (1 << 7))
 
 
-LUAI_DATA const char *const luaP_opnames[NUM_OPCODES+1];  /* opcode names */
+LUAI_DDEC const char *const luaP_opnames[NUM_OPCODES+1];  /* opcode names */
 
 
 /* number of list items to accumulate before a SETLIST instruction */
diff --git a/src/loslib.c b/src/loslib.c
index da06a57..585ba78 100644..100755
--- a/src/loslib.c
+++ b/src/loslib.c
@@ -1,5 +1,5 @@
 /*
-** $Id: loslib.c,v 1.19.1.3 2008/01/18 16:38:18 roberto Exp $
+** $Id: loslib.c,v 1.35 2011/06/20 16:50:59 roberto Exp $
 ** Standard Operating System library
 ** See Copyright Notice in lua.h
 */
@@ -20,37 +20,67 @@
 #include "lualib.h"
 
 
-static int os_pushresult (lua_State *L, int i, const char *filename) {
-  int en = errno;  /* calls to Lua API may change this value */
-  if (i) {
-    lua_pushboolean(L, 1);
-    return 1;
-  }
-  else {
-    lua_pushnil(L);
-    lua_pushfstring(L, "%s: %s", filename, strerror(en));
-    lua_pushinteger(L, en);
-    return 3;
-  }
-}
+/*
+** list of valid conversion specifiers for the 'strftime' function
+*/
+#if !defined(LUA_STRFTIMEOPTIONS)
+
+#if !defined(LUA_USE_POSIX)
+#define LUA_STRFTIMEOPTIONS     { "aAbBcdHIjmMpSUwWxXyYz%", "" }
+#else
+#define LUA_STRFTIMEOPTIONS     { "aAbBcCdDeFgGhHIjmMnprRStTuUVwWxXyYzZ%", "", \
+                                "E", "cCxXyY",  \
+                                "O", "deHImMSuUVwWy" }
+#endif
+
+#endif
+
+
+
+/*
+** By default, Lua uses tmpnam except when POSIX is available, where it
+** uses mkstemp.
+*/
+#if defined(LUA_USE_MKSTEMP)
+#include <unistd.h>
+#define LUA_TMPNAMBUFSIZE       32
+#define lua_tmpnam(b,e) { \
+        strcpy(b, "/tmp/lua_XXXXXX"); \
+        e = mkstemp(b); \
+        if (e != -1) close(e); \
+        e = (e == -1); }
+
+#elif !defined(lua_tmpnam)
+
+#define LUA_TMPNAMBUFSIZE       L_tmpnam
+#define lua_tmpnam(b,e)         { e = (tmpnam(b) == NULL); }
+
+#endif
+
 
 
 static int os_execute (lua_State *L) {
-  lua_pushinteger(L, system(luaL_optstring(L, 1, NULL)));
-  return 1;
+  const char *cmd = luaL_optstring(L, 1, NULL);
+  int stat = system(cmd);
+  if (cmd != NULL)
+    return luaL_execresult(L, stat);
+  else {
+    lua_pushboolean(L, stat);  /* true if there is a shell */
+    return 1;
+  }
 }
 
 
 static int os_remove (lua_State *L) {
   const char *filename = luaL_checkstring(L, 1);
-  return os_pushresult(L, remove(filename) == 0, filename);
+  return luaL_fileresult(L, remove(filename) == 0, filename);
 }
 
 
 static int os_rename (lua_State *L) {
   const char *fromname = luaL_checkstring(L, 1);
   const char *toname = luaL_checkstring(L, 2);
-  return os_pushresult(L, rename(fromname, toname) == 0, fromname);
+  return luaL_fileresult(L, rename(fromname, toname) == 0, fromname);
 }
 
 
@@ -107,11 +137,10 @@ static int getboolfield (lua_State *L, const char *key) {
 
 
 static int getfield (lua_State *L, const char *key, int d) {
-  int res;
+  int res, isnum;
   lua_getfield(L, -1, key);
-  if (lua_isnumber(L, -1))
-    res = (int)lua_tointeger(L, -1);
-  else {
+  res = (int)lua_tointegerx(L, -1, &isnum);
+  if (!isnum) {
     if (d < 0)
       return luaL_error(L, "field " LUA_QS " missing in date table", key);
     res = d;
@@ -121,6 +150,30 @@ static int getfield (lua_State *L, const char *key, int d) {
 }
 
 
+static const char *checkoption (lua_State *L, const char *conv, char *buff) {
+  static const char *const options[] = LUA_STRFTIMEOPTIONS;
+  unsigned int i;
+  for (i = 0; i < sizeof(options)/sizeof(options[0]); i += 2) {
+    if (*conv != '\0' && strchr(options[i], *conv) != NULL) {
+      buff[1] = *conv;
+      if (*options[i + 1] == '\0') {  /* one-char conversion specifier? */
+        buff[2] = '\0';  /* end buffer */
+        return conv + 1;
+      }
+      else if (*(conv + 1) != '\0' &&
+               strchr(options[i + 1], *(conv + 1)) != NULL) {
+        buff[2] = *(conv + 1);  /* valid two-char conversion specifier */
+        buff[3] = '\0';  /* end buffer */
+        return conv + 2;
+      }
+    }
+  }
+  luaL_argerror(L, 1,
+    lua_pushfstring(L, "invalid conversion specifier '%%%s'", conv));
+  return conv;  /* to avoid warnings */
+}
+
+
 static int os_date (lua_State *L) {
   const char *s = luaL_optstring(L, 1, "%c");
   time_t t = luaL_opt(L, (time_t)luaL_checknumber, 2, time(NULL));
@@ -146,17 +199,17 @@ static int os_date (lua_State *L) {
     setboolfield(L, "isdst", stm->tm_isdst);
   }
   else {
-    char cc[3];
+    char cc[4];
     luaL_Buffer b;
-    cc[0] = '%'; cc[2] = '\0';
+    cc[0] = '%';
     luaL_buffinit(L, &b);
-    for (; *s; s++) {
-      if (*s != '%' || *(s + 1) == '\0')  /* no conversion specifier? */
-        luaL_addchar(&b, *s);
+    while (*s) {
+      if (*s != '%')  /* no conversion specifier? */
+        luaL_addchar(&b, *s++);
       else {
         size_t reslen;
         char buff[200];  /* should be big enough for any conversion result */
-        cc[1] = *(++s);
+        s = checkoption(L, s + 1, cc);
         reslen = strftime(buff, sizeof(buff), cc, stm);
         luaL_addlstring(&b, buff, reslen);
       }
@@ -214,9 +267,17 @@ static int os_setlocale (lua_State *L) {
 
 
 static int os_exit (lua_State *L) {
-  exit(luaL_optint(L, 1, EXIT_SUCCESS));
+  int status;
+  if (lua_isboolean(L, 1))
+    status = (lua_toboolean(L, 1) ? EXIT_SUCCESS : EXIT_FAILURE);
+  else
+    status = luaL_optint(L, 1, EXIT_SUCCESS);
+  if (lua_toboolean(L, 2))
+    lua_close(L);
+  exit(status);
 }
 
+
 static const luaL_Reg syslib[] = {
   {"clock",     os_clock},
   {"date",      os_date},
@@ -236,8 +297,8 @@ static const luaL_Reg syslib[] = {
 
 
 
-LUALIB_API int luaopen_os (lua_State *L) {
-  luaL_register(L, LUA_OSLIBNAME, syslib);
+LUAMOD_API int luaopen_os (lua_State *L) {
+  luaL_newlib(L, syslib);
   return 1;
 }
 
diff --git a/src/lparser.c b/src/lparser.c
index 1e2a9a8..d9c4173 100644..100755
--- a/src/lparser.c
+++ b/src/lparser.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lparser.c,v 2.42.1.3 2007/12/28 15:32:23 roberto Exp $
+** $Id: lparser.c,v 2.113 2011/07/02 15:58:14 roberto Exp $
 ** Lua Parser
 ** See Copyright Notice in lua.h
 */
@@ -27,11 +27,13 @@
 
 
 
-#define hasmultret(k)		((k) == VCALL || (k) == VVARARG)
+/* maximum number of local variables per function (must be smaller
+   than 250, due to the bytecode format) */
+#define MAXVARS		200
+
 
-#define getlocvar(fs, i)	((fs)->f->locvars[(fs)->actvar[i]])
+#define hasmultret(k)		((k) == VCALL || (k) == VVARARG)
 
-#define luaY_checklimit(fs,v,l,m)	if ((v)>(l)) errorlimit(fs,l,m)
 
 
 /*
@@ -39,10 +41,11 @@
 */
 typedef struct BlockCnt {
   struct BlockCnt *previous;  /* chain */
-  int breaklist;  /* list of jumps out of this loop */
-  lu_byte nactvar;  /* # active locals outside the breakable structure */
+  int firstlabel;  /* index of first label in this block */
+  int firstgoto;  /* index of first pending goto in this block */
+  lu_byte nactvar;  /* # active locals outside the block */
   lu_byte upval;  /* true if some variable in the block is an upvalue */
-  lu_byte isbreakable;  /* true if `block' is a loop */
+  lu_byte isloop;  /* true if `block' is a loop */
 } BlockCnt;
 
 
@@ -50,11 +53,13 @@ typedef struct BlockCnt {
 /*
 ** prototypes for recursive non-terminal functions
 */
-static void chunk (LexState *ls);
+static void statement (LexState *ls);
 static void expr (LexState *ls, expdesc *v);
 
 
 static void anchor_token (LexState *ls) {
+  /* last token from outer function must be EOS */
+  lua_assert(ls->fs != NULL || ls->t.token == TK_EOS);
   if (ls->t.token == TK_NAME || ls->t.token == TK_STRING) {
     TString *ts = ls->t.seminfo.ts;
     luaX_newstring(ls, getstr(ts), ts->tsv.len);
@@ -62,18 +67,33 @@ static void anchor_token (LexState *ls) {
 }
 
 
+/* semantic error */
+static void semerror (LexState *ls, const char *msg) {
+  ls->t.token = 0;  /* remove 'near to' from final message */
+  luaX_syntaxerror(ls, msg);
+}
+
+
 static void error_expected (LexState *ls, int token) {
   luaX_syntaxerror(ls,
-      luaO_pushfstring(ls->L, LUA_QS " expected", luaX_token2str(ls, token)));
+      luaO_pushfstring(ls->L, "%s expected", luaX_token2str(ls, token)));
 }
 
 
 static void errorlimit (FuncState *fs, int limit, const char *what) {
-  const char *msg = (fs->f->linedefined == 0) ?
-    luaO_pushfstring(fs->L, "main function has more than %d %s", limit, what) :
-    luaO_pushfstring(fs->L, "function at line %d has more than %d %s",
-                            fs->f->linedefined, limit, what);
-  luaX_lexerror(fs->ls, msg, 0);
+  const char *msg;
+  int line = fs->f->linedefined;
+  const char *where = (line == 0)
+                      ? "main function"
+                      : luaO_pushfstring(fs->L, "function at line %d", line);
+  msg = luaO_pushfstring(fs->L, "too many %s (limit is %d) in %s",
+                                what, limit, where);
+  luaX_syntaxerror(fs->ls, msg);
+}
+
+
+static void checklimit (FuncState *fs, int v, int l, const char *what) {
+  if (v > l) errorlimit(fs, l, what);
 }
 
 
@@ -91,6 +111,7 @@ static void check (LexState *ls, int c) {
     error_expected(ls, c);
 }
 
+
 static void checknext (LexState *ls, int c) {
   check(ls, c);
   luaX_next(ls);
@@ -107,7 +128,7 @@ static void check_match (LexState *ls, int what, int who, int where) {
       error_expected(ls, what);
     else {
       luaX_syntaxerror(ls, luaO_pushfstring(ls->L,
-             LUA_QS " expected (to close " LUA_QS " at line %d)",
+             "%s expected (to close %s at line %d)",
               luaX_token2str(ls, what), luaX_token2str(ls, who), where));
     }
   }
@@ -126,7 +147,7 @@ static TString *str_checkname (LexState *ls) {
 static void init_exp (expdesc *e, expkind k, int i) {
   e->f = e->t = NO_JUMP;
   e->k = k;
-  e->u.s.info = i;
+  e->u.info = i;
 }
 
 
@@ -135,7 +156,7 @@ static void codestring (LexState *ls, expdesc *e, TString *s) {
 }
 
 
-static void checkname(LexState *ls, expdesc *e) {
+static void checkname (LexState *ls, expdesc *e) {
   codestring(ls, e, str_checkname(ls));
 }
 
@@ -145,7 +166,7 @@ static int registerlocalvar (LexState *ls, TString *varname) {
   Proto *f = fs->f;
   int oldsize = f->sizelocvars;
   luaM_growvector(ls->L, f->locvars, fs->nlocvars, f->sizelocvars,
-                  LocVar, SHRT_MAX, "too many local variables");
+                  LocVar, SHRT_MAX, "local variables");
   while (oldsize < f->sizelocvars) f->locvars[oldsize++].varname = NULL;
   f->locvars[fs->nlocvars].varname = varname;
   luaC_objbarrier(ls->L, f, varname);
@@ -153,14 +174,30 @@ static int registerlocalvar (LexState *ls, TString *varname) {
 }
 
 
-#define new_localvarliteral(ls,v,n) \
-  new_localvar(ls, luaX_newstring(ls, "" v, (sizeof(v)/sizeof(char))-1), n)
+static void new_localvar (LexState *ls, TString *name) {
+  FuncState *fs = ls->fs;
+  Dyndata *dyd = ls->dyd;
+  int reg = registerlocalvar(ls, name);
+  checklimit(fs, dyd->actvar.n + 1 - fs->firstlocal,
+                  MAXVARS, "local variables");
+  luaM_growvector(ls->L, dyd->actvar.arr, dyd->actvar.n + 1,
+                  dyd->actvar.size, Vardesc, MAX_INT, "local variables");
+  dyd->actvar.arr[dyd->actvar.n++].idx = cast(unsigned short, reg);
+}
 
 
-static void new_localvar (LexState *ls, TString *name, int n) {
-  FuncState *fs = ls->fs;
-  luaY_checklimit(fs, fs->nactvar+n+1, LUAI_MAXVARS, "local variables");
-  fs->actvar[fs->nactvar+n] = cast(unsigned short, registerlocalvar(ls, name));
+static void new_localvarliteral_ (LexState *ls, const char *name, size_t sz) {
+  new_localvar(ls, luaX_newstring(ls, name, sz));
+}
+
+#define new_localvarliteral(ls,v) \
+	new_localvarliteral_(ls, "" v, (sizeof(v)/sizeof(char))-1)
+
+
+static LocVar *getlocvar (FuncState *fs, int i) {
+  int idx = fs->ls->dyd->actvar.arr[fs->firstlocal + i].idx;
+  lua_assert(idx < fs->nlocvars);
+  return &fs->f->locvars[idx];
 }
 
 
@@ -168,77 +205,88 @@ static void adjustlocalvars (LexState *ls, int nvars) {
   FuncState *fs = ls->fs;
   fs->nactvar = cast_byte(fs->nactvar + nvars);
   for (; nvars; nvars--) {
-    getlocvar(fs, fs->nactvar - nvars).startpc = fs->pc;
+    getlocvar(fs, fs->nactvar - nvars)->startpc = fs->pc;
   }
 }
 
 
-static void removevars (LexState *ls, int tolevel) {
-  FuncState *fs = ls->fs;
+static void removevars (FuncState *fs, int tolevel) {
+  fs->ls->dyd->actvar.n -= (fs->nactvar - tolevel);
   while (fs->nactvar > tolevel)
-    getlocvar(fs, --fs->nactvar).endpc = fs->pc;
+    getlocvar(fs, --fs->nactvar)->endpc = fs->pc;
 }
 
 
-static int indexupvalue (FuncState *fs, TString *name, expdesc *v) {
+static int searchupvalue (FuncState *fs, TString *name) {
   int i;
+  Upvaldesc *up = fs->f->upvalues;
+  for (i = 0; i < fs->nups; i++) {
+    if (eqstr(up[i].name, name)) return i;
+  }
+  return -1;  /* not found */
+}
+
+
+static int newupvalue (FuncState *fs, TString *name, expdesc *v) {
   Proto *f = fs->f;
   int oldsize = f->sizeupvalues;
-  for (i=0; i<f->nups; i++) {
-    if (fs->upvalues[i].k == v->k && fs->upvalues[i].info == v->u.s.info) {
-      lua_assert(f->upvalues[i] == name);
-      return i;
-    }
-  }
-  /* new one */
-  luaY_checklimit(fs, f->nups + 1, LUAI_MAXUPVALUES, "upvalues");
-  luaM_growvector(fs->L, f->upvalues, f->nups, f->sizeupvalues,
-                  TString *, MAX_INT, "");
-  while (oldsize < f->sizeupvalues) f->upvalues[oldsize++] = NULL;
-  f->upvalues[f->nups] = name;
+  checklimit(fs, fs->nups + 1, MAXUPVAL, "upvalues");
+  luaM_growvector(fs->L, f->upvalues, fs->nups, f->sizeupvalues,
+                  Upvaldesc, MAXUPVAL, "upvalues");
+  while (oldsize < f->sizeupvalues) f->upvalues[oldsize++].name = NULL;
+  f->upvalues[fs->nups].instack = (v->k == VLOCAL);
+  f->upvalues[fs->nups].idx = cast_byte(v->u.info);
+  f->upvalues[fs->nups].name = name;
   luaC_objbarrier(fs->L, f, name);
-  lua_assert(v->k == VLOCAL || v->k == VUPVAL);
-  fs->upvalues[f->nups].k = cast_byte(v->k);
-  fs->upvalues[f->nups].info = cast_byte(v->u.s.info);
-  return f->nups++;
+  return fs->nups++;
 }
 
 
 static int searchvar (FuncState *fs, TString *n) {
   int i;
   for (i=fs->nactvar-1; i >= 0; i--) {
-    if (n == getlocvar(fs, i).varname)
+    if (eqstr(n, getlocvar(fs, i)->varname))
       return i;
   }
   return -1;  /* not found */
 }
 
 
+/*
+  Mark block where variable at given level was defined
+  (to emit close instructions later).
+*/
 static void markupval (FuncState *fs, int level) {
   BlockCnt *bl = fs->bl;
-  while (bl && bl->nactvar > level) bl = bl->previous;
-  if (bl) bl->upval = 1;
+  while (bl->nactvar > level) bl = bl->previous;
+  bl->upval = 1;
 }
 
 
+/*
+  Find variable with given name 'n'. If it is an upvalue, add this
+  upvalue into all intermediate functions.
+*/
 static int singlevaraux (FuncState *fs, TString *n, expdesc *var, int base) {
-  if (fs == NULL) {  /* no more levels? */
-    init_exp(var, VGLOBAL, NO_REG);  /* default is global variable */
-    return VGLOBAL;
-  }
+  if (fs == NULL)  /* no more levels? */
+    return VVOID;  /* default is global */
   else {
-    int v = searchvar(fs, n);  /* look up at current level */
-    if (v >= 0) {
-      init_exp(var, VLOCAL, v);
+    int v = searchvar(fs, n);  /* look up locals at current level */
+    if (v >= 0) {  /* found? */
+      init_exp(var, VLOCAL, v);  /* variable is local */
       if (!base)
         markupval(fs, v);  /* local will be used as an upval */
       return VLOCAL;
     }
-    else {  /* not found at current level; try upper one */
-      if (singlevaraux(fs->prev, n, var, 0) == VGLOBAL)
-        return VGLOBAL;
-      var->u.s.info = indexupvalue(fs, n, var);  /* else was LOCAL or UPVAL */
-      var->k = VUPVAL;  /* upvalue in this level */
+    else {  /* not found as local at current level; try upvalues */
+      int idx = searchupvalue(fs, n);  /* try existing upvalues */
+      if (idx < 0) {  /* not found? */
+        if (singlevaraux(fs->prev, n, var, 0) == VVOID) /* try upper levels */
+          return VVOID;  /* not found; is a global */
+        /* else was LOCAL or UPVAL */
+        idx  = newupvalue(fs, n, var);  /* will be a new upvalue */
+      }
+      init_exp(var, VUPVAL, idx);
       return VUPVAL;
     }
   }
@@ -248,8 +296,13 @@ static int singlevaraux (FuncState *fs, TString *n, expdesc *var, int base) {
 static void singlevar (LexState *ls, expdesc *var) {
   TString *varname = str_checkname(ls);
   FuncState *fs = ls->fs;
-  if (singlevaraux(fs, varname, var, 1) == VGLOBAL)
-    var->u.s.info = luaK_stringK(fs, varname);  /* info points to global name */
+  if (singlevaraux(fs, varname, var, 1) == VVOID) {  /* global name? */
+    expdesc key;
+    singlevaraux(fs, ls->envn, var, 1);  /* get environment variable */
+    lua_assert(var->k == VLOCAL || var->k == VUPVAL);
+    codestring(ls, &key, varname);  /* key is variable name */
+    luaK_indexed(fs, var, &key);  /* env[varname] */
+  }
 }
 
 
@@ -274,18 +327,116 @@ static void adjust_assign (LexState *ls, int nvars, int nexps, expdesc *e) {
 
 
 static void enterlevel (LexState *ls) {
-  if (++ls->L->nCcalls > LUAI_MAXCCALLS)
-	luaX_lexerror(ls, "chunk has too many syntax levels", 0);
+  global_State *g = G(ls->L);
+  ++g->nCcalls;
+  checklimit(ls->fs, g->nCcalls, LUAI_MAXCCALLS, "syntax levels");
+}
+
+
+#define leavelevel(ls)	(G((ls)->L)->nCcalls--)
+
+
+static void closegoto (LexState *ls, int g, Labeldesc *label) {
+  int i;
+  FuncState *fs = ls->fs;
+  Labellist *gl = &ls->dyd->gt;
+  Labeldesc *gt = &gl->arr[g];
+  lua_assert(eqstr(gt->name, label->name));
+  if (gt->nactvar < label->nactvar) {
+    const char *msg = luaO_pushfstring(ls->L,
+      "<goto %s> at line %d jumps into the scope of local " LUA_QS,
+      getstr(gt->name), gt->line, getstr(getlocvar(fs, gt->nactvar)->varname));
+    semerror(ls, msg);
+  }
+  luaK_patchlist(fs, gt->pc, label->pc);
+  /* remove goto from pending list */
+  for (i = g; i < gl->n - 1; i++)
+    gl->arr[i] = gl->arr[i + 1];
+  gl->n--;
 }
 
 
-#define leavelevel(ls)	((ls)->L->nCcalls--)
+/*
+** try to close a goto with existing labels; this solves backward jumps
+*/
+static int findlabel (LexState *ls, int g) {
+  int i;
+  BlockCnt *bl = ls->fs->bl;
+  Dyndata *dyd = ls->dyd;
+  Labeldesc *gt = &dyd->gt.arr[g];
+  /* check labels in current block for a match */
+  for (i = bl->firstlabel; i < dyd->label.n; i++) {
+    Labeldesc *lb = &dyd->label.arr[i];
+    if (eqstr(lb->name, gt->name)) {  /* correct label? */
+      if (gt->nactvar > lb->nactvar &&
+          (bl->upval || dyd->label.n > bl->firstlabel))
+        luaK_patchclose(ls->fs, gt->pc, lb->nactvar);
+      closegoto(ls, g, lb);  /* close it */
+      return 1;
+    }
+  }
+  return 0;  /* label not found; cannot close goto */
+}
 
 
-static void enterblock (FuncState *fs, BlockCnt *bl, lu_byte isbreakable) {
-  bl->breaklist = NO_JUMP;
-  bl->isbreakable = isbreakable;
+static int newlabelentry (LexState *ls, Labellist *l, TString *name,
+                          int line, int pc) {
+  int n = l->n;
+  luaM_growvector(ls->L, l->arr, n, l->size, Labeldesc, MAX_INT, "labels");
+  l->arr[n].name = name;
+  l->arr[n].line = line;
+  l->arr[n].nactvar = ls->fs->nactvar;
+  l->arr[n].pc = pc;
+  l->n++;
+  return n;
+}
+
+
+/*
+** check whether new label 'lb' matches any pending gotos in current
+** block; solves forward jumps
+*/
+static void findgotos (LexState *ls, Labeldesc *lb) {
+  Labellist *gl = &ls->dyd->gt;
+  int i = ls->fs->bl->firstgoto;
+  while (i < gl->n) {
+    if (eqstr(gl->arr[i].name, lb->name))
+      closegoto(ls, i, lb);
+    else
+      i++;
+  }
+}
+
+
+/*
+** "export" pending gotos to outer level, to check them against
+** outer labels; if the block being exited has upvalues, and
+** the goto exits the scope of any variable (which can be the
+** upvalue), close those variables being exited.
+*/
+static void movegotosout (FuncState *fs, BlockCnt *bl) {
+  int i = bl->firstgoto;
+  Labellist *gl = &fs->ls->dyd->gt;
+  /* correct pending gotos to current block and try to close it
+     with visible labels */ 
+  while (i < gl->n) {
+    Labeldesc *gt = &gl->arr[i];
+    if (gt->nactvar > bl->nactvar) {
+      if (bl->upval)
+        luaK_patchclose(fs, gt->pc, bl->nactvar);
+      gt->nactvar = bl->nactvar;
+    }
+    if (!findlabel(fs->ls, i))
+      i++;  /* move to next one */
+  }
+}
+
+
+static void enterblock (FuncState *fs, BlockCnt *bl, lu_byte isloop) {
+  bl->isloop = isloop;
   bl->nactvar = fs->nactvar;
+  bl->firstlabel = fs->ls->dyd->label.n;
+  bl->firstgoto = fs->ls->dyd->gt.n;
   bl->upval = 0;
   bl->previous = fs->bl;
   fs->bl = bl;
@@ -293,63 +444,101 @@ static void enterblock (FuncState *fs, BlockCnt *bl, lu_byte isbreakable) {
 }
 
 
+/*
+** create a label named "break" to resolve break statements
+*/
+static void breaklabel (LexState *ls) {
+  TString *n = luaS_new(ls->L, "break");
+  int l = newlabelentry(ls, &ls->dyd->label, n, 0, ls->fs->pc);
+  findgotos(ls, &ls->dyd->label.arr[l]);
+}
+
+/*
+** generates an error for an undefined 'goto'; choose appropriate
+** message when label name is a reserved word (which can only be 'break')
+*/
+static void undefgoto (LexState *ls, Labeldesc *gt) {
+  const char *msg = (gt->name->tsv.reserved > 0)
+                    ? "<%s> at line %d not inside a loop"
+                    : "no visible label " LUA_QS " for <goto> at line %d";
+  msg = luaO_pushfstring(ls->L, msg, getstr(gt->name), gt->line);
+  semerror(ls, msg);
+}
+
+
 static void leaveblock (FuncState *fs) {
   BlockCnt *bl = fs->bl;
+  LexState *ls = fs->ls;
+  if (bl->previous && bl->upval) {
+    /* create a 'jump to here' to close upvalues */
+    int j = luaK_jump(fs);
+    luaK_patchclose(fs, j, bl->nactvar);
+    luaK_patchtohere(fs, j);
+  }
+  if (bl->isloop)
+    breaklabel(ls);  /* close pending breaks */
   fs->bl = bl->previous;
-  removevars(fs->ls, bl->nactvar);
-  if (bl->upval)
-    luaK_codeABC(fs, OP_CLOSE, bl->nactvar, 0, 0);
-  /* a block either controls scope or breaks (never both) */
-  lua_assert(!bl->isbreakable || !bl->upval);
+  removevars(fs, bl->nactvar);
   lua_assert(bl->nactvar == fs->nactvar);
   fs->freereg = fs->nactvar;  /* free registers */
-  luaK_patchtohere(fs, bl->breaklist);
+  ls->dyd->label.n = bl->firstlabel;  /* remove local labels */
+  if (bl->previous)  /* inner block? */
+    movegotosout(fs, bl);  /* update pending gotos to outer block */
+  else if (bl->firstgoto < ls->dyd->gt.n)  /* pending gotos in outer block? */
+    undefgoto(ls, &ls->dyd->gt.arr[bl->firstgoto]);  /* error */
 }
 
 
-static void pushclosure (LexState *ls, FuncState *func, expdesc *v) {
-  FuncState *fs = ls->fs;
-  Proto *f = fs->f;
-  int oldsize = f->sizep;
-  int i;
-  luaM_growvector(ls->L, f->p, fs->np, f->sizep, Proto *,
-                  MAXARG_Bx, "constant table overflow");
-  while (oldsize < f->sizep) f->p[oldsize++] = NULL;
-  f->p[fs->np++] = func->f;
-  luaC_objbarrier(ls->L, f, func->f);
-  init_exp(v, VRELOCABLE, luaK_codeABx(fs, OP_CLOSURE, 0, fs->np-1));
-  for (i=0; i<func->f->nups; i++) {
-    OpCode o = (func->upvalues[i].k == VLOCAL) ? OP_MOVE : OP_GETUPVAL;
-    luaK_codeABC(fs, o, 0, func->upvalues[i].info, 0);
+/*
+** adds prototype being created into its parent list of prototypes
+** and codes instruction to create new closure
+*/
+static void codeclosure (LexState *ls, Proto *clp, expdesc *v) {
+  FuncState *fs = ls->fs->prev;
+  Proto *f = fs->f;  /* prototype of function creating new closure */
+  if (fs->np >= f->sizep) {
+    int oldsize = f->sizep;
+    luaM_growvector(ls->L, f->p, fs->np, f->sizep, Proto *,
+                    MAXARG_Bx, "functions");
+    while (oldsize < f->sizep) f->p[oldsize++] = NULL;
   }
+  f->p[fs->np++] = clp;
+  luaC_objbarrier(ls->L, f, clp);
+  init_exp(v, VRELOCABLE, luaK_codeABx(fs, OP_CLOSURE, 0, fs->np-1));
+  luaK_exp2nextreg(fs, v);  /* fix it at stack top (for GC) */
 }
 
 
-static void open_func (LexState *ls, FuncState *fs) {
+static void open_func (LexState *ls, FuncState *fs, BlockCnt *bl) {
   lua_State *L = ls->L;
-  Proto *f = luaF_newproto(L);
-  fs->f = f;
+  Proto *f;
   fs->prev = ls->fs;  /* linked list of funcstates */
   fs->ls = ls;
   fs->L = L;
   ls->fs = fs;
   fs->pc = 0;
-  fs->lasttarget = -1;
+  fs->lasttarget = 0;
   fs->jpc = NO_JUMP;
   fs->freereg = 0;
   fs->nk = 0;
   fs->np = 0;
+  fs->nups = 0;
   fs->nlocvars = 0;
   fs->nactvar = 0;
+  fs->firstlocal = ls->dyd->actvar.n;
   fs->bl = NULL;
+  f = luaF_newproto(L);
+  fs->f = f;
   f->source = ls->source;
   f->maxstacksize = 2;  /* registers 0/1 are always valid */
-  fs->h = luaH_new(L, 0, 0);
-  /* anchor table of constants and prototype (to avoid being collected) */
-  sethvalue2s(L, L->top, fs->h);
-  incr_top(L);
+  /* anchor prototype (to avoid being collected) */
   setptvalue2s(L, L->top, f);
   incr_top(L);
+  fs->h = luaH_new(L);
+  /* anchor table of constants (to avoid being collected) */
+  sethvalue2s(L, L->top, fs->h);
+  incr_top(L);
+  enterblock(fs, bl, 0);
 }
 
 
@@ -357,8 +546,8 @@ static void close_func (LexState *ls) {
   lua_State *L = ls->L;
   FuncState *fs = ls->fs;
   Proto *f = fs->f;
-  removevars(ls, 0);
   luaK_ret(fs, 0, 0);  /* final return */
+  leaveblock(fs);
   luaM_reallocvector(L, f->code, f->sizecode, fs->pc, Instruction);
   f->sizecode = fs->pc;
   luaM_reallocvector(L, f->lineinfo, f->sizelineinfo, fs->pc, int);
@@ -369,32 +558,28 @@ static void close_func (LexState *ls) {
   f->sizep = fs->np;
   luaM_reallocvector(L, f->locvars, f->sizelocvars, fs->nlocvars, LocVar);
   f->sizelocvars = fs->nlocvars;
-  luaM_reallocvector(L, f->upvalues, f->sizeupvalues, f->nups, TString *);
-  f->sizeupvalues = f->nups;
-  lua_assert(luaG_checkcode(f));
+  luaM_reallocvector(L, f->upvalues, f->sizeupvalues, fs->nups, Upvaldesc);
+  f->sizeupvalues = fs->nups;
   lua_assert(fs->bl == NULL);
   ls->fs = fs->prev;
-  L->top -= 2;  /* remove table and prototype from the stack */
-  /* last token read was anchored in defunct function; must reanchor it */
-  if (fs) anchor_token(ls);
+  /* last token read was anchored in defunct function; must re-anchor it */
+  anchor_token(ls);
+  L->top--;  /* pop table of constants */
+  luaC_checkGC(L);
+  L->top--;  /* pop prototype (after possible collection) */
 }
 
 
-Proto *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff, const char *name) {
-  struct LexState lexstate;
-  struct FuncState funcstate;
-  lexstate.buff = buff;
-  luaX_setinput(L, &lexstate, z, luaS_new(L, name));
-  open_func(&lexstate, &funcstate);
-  funcstate.f->is_vararg = VARARG_ISVARARG;  /* main func. is always vararg */
-  luaX_next(&lexstate);  /* read first token */
-  chunk(&lexstate);
-  check(&lexstate, TK_EOS);
-  close_func(&lexstate);
-  lua_assert(funcstate.prev == NULL);
-  lua_assert(funcstate.f->nups == 0);
-  lua_assert(lexstate.fs == NULL);
-  return funcstate.f;
+/*
+** opens the main function, which is a regular vararg function with an
+** upvalue named LUA_ENV
+*/
+static void open_mainfunc (LexState *ls, FuncState *fs, BlockCnt *bl) {
+  expdesc v;
+  open_func(ls, fs, bl);
+  fs->f->is_vararg = 1;  /* main function is always vararg */
+  init_exp(&v, VLOCAL, 0);
+  newupvalue(fs, ls->envn, &v);  /* create environment upvalue */
 }
 
 
@@ -404,11 +589,39 @@ Proto *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff, const char *name) {
 /*============================================================*/
 
 
-static void field (LexState *ls, expdesc *v) {
-  /* field -> ['.' | ':'] NAME */
+/*
+** check whether current token is in the follow set of a block.
+** 'until' closes syntactical blocks, but do not close scope,
+** so it handled in separate.
+*/
+static int block_follow (LexState *ls, int withuntil) {
+  switch (ls->t.token) {
+    case TK_ELSE: case TK_ELSEIF:
+    case TK_END: case TK_EOS:
+      return 1;
+    case TK_UNTIL: return withuntil;
+    default: return 0;
+  }
+}
+
+
+static void statlist (LexState *ls) {
+  /* statlist -> { stat [`;'] } */
+  while (!block_follow(ls, 1)) {
+    if (ls->t.token == TK_RETURN) {
+      statement(ls);
+      return;  /* 'return' must be last statement */
+    }
+    statement(ls);
+  }
+}
+
+
+static void fieldsel (LexState *ls, expdesc *v) {
+  /* fieldsel -> ['.' | ':'] NAME */
   FuncState *fs = ls->fs;
   expdesc key;
-  luaK_exp2anyreg(fs, v);
+  luaK_exp2anyregup(fs, v);
   luaX_next(ls);  /* skip the dot or colon */
   checkname(ls, &key);
   luaK_indexed(fs, v, &key);
@@ -447,7 +660,7 @@ static void recfield (LexState *ls, struct ConsControl *cc) {
   expdesc key, val;
   int rkkey;
   if (ls->t.token == TK_NAME) {
-    luaY_checklimit(fs, cc->nh, MAX_INT, "items in a constructor");
+    checklimit(fs, cc->nh, MAX_INT, "items in a constructor");
     checkname(ls, &key);
   }
   else  /* ls->t.token == '[' */
@@ -456,7 +669,7 @@ static void recfield (LexState *ls, struct ConsControl *cc) {
   checknext(ls, '=');
   rkkey = luaK_exp2RK(fs, &key);
   expr(ls, &val);
-  luaK_codeABC(fs, OP_SETTABLE, cc->t->u.s.info, rkkey, luaK_exp2RK(fs, &val));
+  luaK_codeABC(fs, OP_SETTABLE, cc->t->u.info, rkkey, luaK_exp2RK(fs, &val));
   fs->freereg = reg;  /* free registers */
 }
 
@@ -466,7 +679,7 @@ static void closelistfield (FuncState *fs, struct ConsControl *cc) {
   luaK_exp2nextreg(fs, &cc->v);
   cc->v.k = VVOID;
   if (cc->tostore == LFIELDS_PER_FLUSH) {
-    luaK_setlist(fs, cc->t->u.s.info, cc->na, cc->tostore);  /* flush */
+    luaK_setlist(fs, cc->t->u.info, cc->na, cc->tostore);  /* flush */
     cc->tostore = 0;  /* no more items pending */
   }
 }
@@ -476,27 +689,51 @@ static void lastlistfield (FuncState *fs, struct ConsControl *cc) {
   if (cc->tostore == 0) return;
   if (hasmultret(cc->v.k)) {
     luaK_setmultret(fs, &cc->v);
-    luaK_setlist(fs, cc->t->u.s.info, cc->na, LUA_MULTRET);
+    luaK_setlist(fs, cc->t->u.info, cc->na, LUA_MULTRET);
     cc->na--;  /* do not count last expression (unknown number of elements) */
   }
   else {
     if (cc->v.k != VVOID)
       luaK_exp2nextreg(fs, &cc->v);
-    luaK_setlist(fs, cc->t->u.s.info, cc->na, cc->tostore);
+    luaK_setlist(fs, cc->t->u.info, cc->na, cc->tostore);
   }
 }
 
 
 static void listfield (LexState *ls, struct ConsControl *cc) {
+  /* listfield -> exp */
   expr(ls, &cc->v);
-  luaY_checklimit(ls->fs, cc->na, MAX_INT, "items in a constructor");
+  checklimit(ls->fs, cc->na, MAX_INT, "items in a constructor");
   cc->na++;
   cc->tostore++;
 }
 
 
+static void field (LexState *ls, struct ConsControl *cc) {
+  /* field -> listfield | recfield */
+  switch(ls->t.token) {
+    case TK_NAME: {  /* may be 'listfield' or 'recfield' */
+      if (luaX_lookahead(ls) != '=')  /* expression? */
+        listfield(ls, cc);
+      else
+        recfield(ls, cc);
+      break;
+    }
+    case '[': {
+      recfield(ls, cc);
+      break;
+    }
+    default: {
+      listfield(ls, cc);
+      break;
+    }
+  }
+}
+
+
 static void constructor (LexState *ls, expdesc *t) {
-  /* constructor -> ?? */
+  /* constructor -> '{' [ field { sep field } [sep] ] '}'
+     sep -> ',' | ';' */
   FuncState *fs = ls->fs;
   int line = ls->linenumber;
   int pc = luaK_codeABC(fs, OP_NEWTABLE, 0, 0, 0);
@@ -505,30 +742,13 @@ static void constructor (LexState *ls, expdesc *t) {
   cc.t = t;
   init_exp(t, VRELOCABLE, pc);
   init_exp(&cc.v, VVOID, 0);  /* no value (yet) */
-  luaK_exp2nextreg(ls->fs, t);  /* fix it at stack top (for gc) */
+  luaK_exp2nextreg(ls->fs, t);  /* fix it at stack top */
   checknext(ls, '{');
   do {
     lua_assert(cc.v.k == VVOID || cc.tostore > 0);
     if (ls->t.token == '}') break;
     closelistfield(fs, &cc);
-    switch(ls->t.token) {
-      case TK_NAME: {  /* may be listfields or recfields */
-        luaX_lookahead(ls);
-        if (ls->lookahead.token != '=')  /* expression? */
-          listfield(ls, &cc);
-        else
-          recfield(ls, &cc);
-        break;
-      }
-      case '[': {  /* constructor_item -> recfield */
-        recfield(ls, &cc);
-        break;
-      }
-      default: {  /* constructor_part -> listfield */
-        listfield(ls, &cc);
-        break;
-      }
-    }
+    field(ls, &cc);
   } while (testnext(ls, ',') || testnext(ls, ';'));
   check_match(ls, '}', '{', line);
   lastlistfield(fs, &cc);
@@ -550,17 +770,13 @@ static void parlist (LexState *ls) {
     do {
       switch (ls->t.token) {
         case TK_NAME: {  /* param -> NAME */
-          new_localvar(ls, str_checkname(ls), nparams++);
+          new_localvar(ls, str_checkname(ls));
+          nparams++;
           break;
         }
         case TK_DOTS: {  /* param -> `...' */
           luaX_next(ls);
-#if defined(LUA_COMPAT_VARARG)
-          /* use `arg' as default name */
-          new_localvarliteral(ls, "arg", nparams++);
-          f->is_vararg = VARARG_HASARG | VARARG_NEEDSARG;
-#endif
-          f->is_vararg |= VARARG_ISVARARG;
+          f->is_vararg = 1;
           break;
         }
         default: luaX_syntaxerror(ls, "<name> or " LUA_QL("...") " expected");
@@ -568,33 +784,34 @@ static void parlist (LexState *ls) {
     } while (!f->is_vararg && testnext(ls, ','));
   }
   adjustlocalvars(ls, nparams);
-  f->numparams = cast_byte(fs->nactvar - (f->is_vararg & VARARG_HASARG));
+  f->numparams = cast_byte(fs->nactvar);
   luaK_reserveregs(fs, fs->nactvar);  /* reserve register for parameters */
 }
 
 
-static void body (LexState *ls, expdesc *e, int needself, int line) {
-  /* body ->  `(' parlist `)' chunk END */
+static void body (LexState *ls, expdesc *e, int ismethod, int line) {
+  /* body ->  `(' parlist `)' block END */
   FuncState new_fs;
-  open_func(ls, &new_fs);
+  BlockCnt bl;
+  open_func(ls, &new_fs, &bl);
   new_fs.f->linedefined = line;
   checknext(ls, '(');
-  if (needself) {
-    new_localvarliteral(ls, "self", 0);
+  if (ismethod) {
+    new_localvarliteral(ls, "self");  /* create 'self' parameter */
     adjustlocalvars(ls, 1);
   }
   parlist(ls);
   checknext(ls, ')');
-  chunk(ls);
+  statlist(ls);
   new_fs.f->lastlinedefined = ls->linenumber;
   check_match(ls, TK_END, TK_FUNCTION, line);
+  codeclosure(ls, new_fs.f, e);
   close_func(ls);
-  pushclosure(ls, &new_fs, e);
 }
 
 
-static int explist1 (LexState *ls, expdesc *v) {
-  /* explist1 -> expr { `,' expr } */
+static int explist (LexState *ls, expdesc *v) {
+  /* explist -> expr { `,' expr } */
   int n = 1;  /* at least one expression */
   expr(ls, v);
   while (testnext(ls, ',')) {
@@ -606,20 +823,17 @@ static int explist1 (LexState *ls, expdesc *v) {
 }
 
 
-static void funcargs (LexState *ls, expdesc *f) {
+static void funcargs (LexState *ls, expdesc *f, int line) {
   FuncState *fs = ls->fs;
   expdesc args;
   int base, nparams;
-  int line = ls->linenumber;
   switch (ls->t.token) {
-    case '(': {  /* funcargs -> `(' [ explist1 ] `)' */
-      if (line != ls->lastline)
-        luaX_syntaxerror(ls,"ambiguous syntax (function call x new statement)");
+    case '(': {  /* funcargs -> `(' [ explist ] `)' */
       luaX_next(ls);
       if (ls->t.token == ')')  /* arg list is empty? */
         args.k = VVOID;
       else {
-        explist1(ls, &args);
+        explist(ls, &args);
         luaK_setmultret(fs, &args);
       }
       check_match(ls, ')', '(', line);
@@ -640,7 +854,7 @@ static void funcargs (LexState *ls, expdesc *f) {
     }
   }
   lua_assert(f->k == VNONRELOC);
-  base = f->u.s.info;  /* base register for call */
+  base = f->u.info;  /* base register for call */
   if (hasmultret(args.k))
     nparams = LUA_MULTRET;  /* open call */
   else {
@@ -691,16 +905,17 @@ static void primaryexp (LexState *ls, expdesc *v) {
   /* primaryexp ->
         prefixexp { `.' NAME | `[' exp `]' | `:' NAME funcargs | funcargs } */
   FuncState *fs = ls->fs;
+  int line = ls->linenumber;
   prefixexp(ls, v);
   for (;;) {
     switch (ls->t.token) {
-      case '.': {  /* field */
-        field(ls, v);
+      case '.': {  /* fieldsel */
+        fieldsel(ls, v);
         break;
       }
       case '[': {  /* `[' exp1 `]' */
         expdesc key;
-        luaK_exp2anyreg(fs, v);
+        luaK_exp2anyregup(fs, v);
         yindex(ls, &key);
         luaK_indexed(fs, v, &key);
         break;
@@ -710,12 +925,12 @@ static void primaryexp (LexState *ls, expdesc *v) {
         luaX_next(ls);
         checkname(ls, &key);
         luaK_self(fs, v, &key);
-        funcargs(ls, v);
+        funcargs(ls, v, line);
         break;
       }
       case '(': case TK_STRING: case '{': {  /* funcargs */
         luaK_exp2nextreg(fs, v);
-        funcargs(ls, v);
+        funcargs(ls, v, line);
         break;
       }
       default: return;
@@ -725,7 +940,7 @@ static void primaryexp (LexState *ls, expdesc *v) {
 
 
 static void simpleexp (LexState *ls, expdesc *v) {
-  /* simpleexp -> NUMBER | STRING | NIL | true | false | ... |
+  /* simpleexp -> NUMBER | STRING | NIL | TRUE | FALSE | ... |
                   constructor | FUNCTION body | primaryexp */
   switch (ls->t.token) {
     case TK_NUMBER: {
@@ -753,7 +968,6 @@ static void simpleexp (LexState *ls, expdesc *v) {
       FuncState *fs = ls->fs;
       check_condition(ls, fs->f->is_vararg,
                       "cannot use " LUA_QL("...") " outside a vararg function");
-      fs->f->is_vararg &= ~VARARG_NEEDSARG;  /* don't need 'arg' */
       init_exp(v, VVARARG, luaK_codeABC(fs, OP_VARARG, 0, 1, 0));
       break;
     }
@@ -811,11 +1025,11 @@ static const struct {
   lu_byte left;  /* left priority for each binary operator */
   lu_byte right; /* right priority */
 } priority[] = {  /* ORDER OPR */
-   {6, 6}, {6, 6}, {7, 7}, {7, 7}, {7, 7},  /* `+' `-' `/' `%' */
-   {10, 9}, {5, 4},                 /* power and concat (right associative) */
-   {3, 3}, {3, 3},                  /* equality and inequality */
-   {3, 3}, {3, 3}, {3, 3}, {3, 3},  /* order */
-   {2, 2}, {1, 1}                   /* logical (and/or) */
+   {6, 6}, {6, 6}, {7, 7}, {7, 7}, {7, 7},  /* `+' `-' `*' `/' `%' */
+   {10, 9}, {5, 4},                 /* ^, .. (right associative) */
+   {3, 3}, {3, 3}, {3, 3},          /* ==, <, <= */
+   {3, 3}, {3, 3}, {3, 3},          /* ~=, >, >= */
+   {2, 2}, {1, 1}                   /* and, or */
 };
 
 #define UNARY_PRIORITY	8  /* priority for unary operators */
@@ -831,9 +1045,10 @@ static BinOpr subexpr (LexState *ls, expdesc *v, unsigned int limit) {
   enterlevel(ls);
   uop = getunopr(ls->t.token);
   if (uop != OPR_NOUNOPR) {
+    int line = ls->linenumber;
     luaX_next(ls);
     subexpr(ls, v, UNARY_PRIORITY);
-    luaK_prefix(ls->fs, uop, v);
+    luaK_prefix(ls->fs, uop, v, line);
   }
   else simpleexp(ls, v);
   /* expand while operators have priorities higher than `limit' */
@@ -841,11 +1056,12 @@ static BinOpr subexpr (LexState *ls, expdesc *v, unsigned int limit) {
   while (op != OPR_NOBINOPR && priority[op].left > limit) {
     expdesc v2;
     BinOpr nextop;
+    int line = ls->linenumber;
     luaX_next(ls);
     luaK_infix(ls->fs, op, v);
     /* read sub-expression with higher priority */
     nextop = subexpr(ls, &v2, priority[op].right);
-    luaK_posfix(ls->fs, op, v, &v2);
+    luaK_posfix(ls->fs, op, v, &v2, line);
     op = nextop;
   }
   leavelevel(ls);
@@ -868,23 +1084,12 @@ static void expr (LexState *ls, expdesc *v) {
 */
 
 
-static int block_follow (int token) {
-  switch (token) {
-    case TK_ELSE: case TK_ELSEIF: case TK_END:
-    case TK_UNTIL: case TK_EOS:
-      return 1;
-    default: return 0;
-  }
-}
-
-
 static void block (LexState *ls) {
-  /* block -> chunk */
+  /* block -> statlist */
   FuncState *fs = ls->fs;
   BlockCnt bl;
   enterblock(fs, &bl, 0);
-  chunk(ls);
-  lua_assert(bl.breaklist == NO_JUMP);
+  statlist(ls);
   leaveblock(fs);
 }
 
@@ -910,19 +1115,21 @@ static void check_conflict (LexState *ls, struct LHS_assign *lh, expdesc *v) {
   int extra = fs->freereg;  /* eventual position to save local variable */
   int conflict = 0;
   for (; lh; lh = lh->prev) {
-    if (lh->v.k == VINDEXED) {
-      if (lh->v.u.s.info == v->u.s.info) {  /* conflict? */
-        conflict = 1;
-        lh->v.u.s.info = extra;  /* previous assignment will use safe copy */
-      }
-      if (lh->v.u.s.aux == v->u.s.info) {  /* conflict? */
-        conflict = 1;
-        lh->v.u.s.aux = extra;  /* previous assignment will use safe copy */
-      }
+    /* conflict in table 't'? */
+    if (lh->v.u.ind.vt == v->k && lh->v.u.ind.t == v->u.info) {
+      conflict = 1;
+      lh->v.u.ind.vt = VLOCAL;
+      lh->v.u.ind.t = extra;  /* previous assignment will use safe copy */
+    }
+    /* conflict in index 'idx'? */
+    if (v->k == VLOCAL && lh->v.u.ind.idx == v->u.info) {
+      conflict = 1;
+      lh->v.u.ind.idx = extra;  /* previous assignment will use safe copy */
     }
   }
   if (conflict) {
-    luaK_codeABC(fs, OP_MOVE, fs->freereg, v->u.s.info, 0);  /* make copy */
+    OpCode op = (v->k == VLOCAL) ? OP_MOVE : OP_GETUPVAL;
+    luaK_codeABC(fs, op, fs->freereg, v->u.info, 0);  /* make copy */
     luaK_reserveregs(fs, 1);
   }
 }
@@ -930,22 +1137,21 @@ static void check_conflict (LexState *ls, struct LHS_assign *lh, expdesc *v) {
 
 static void assignment (LexState *ls, struct LHS_assign *lh, int nvars) {
   expdesc e;
-  check_condition(ls, VLOCAL <= lh->v.k && lh->v.k <= VINDEXED,
-                      "syntax error");
+  check_condition(ls, vkisvar(lh->v.k), "syntax error");
   if (testnext(ls, ',')) {  /* assignment -> `,' primaryexp assignment */
     struct LHS_assign nv;
     nv.prev = lh;
     primaryexp(ls, &nv.v);
-    if (nv.v.k == VLOCAL)
+    if (nv.v.k != VINDEXED)
       check_conflict(ls, lh, &nv.v);
-    luaY_checklimit(ls->fs, nvars, LUAI_MAXCCALLS - ls->L->nCcalls,
-                    "variables in assignment");
+    checklimit(ls->fs, nvars, LUAI_MAXCCALLS - G(ls->L)->nCcalls,
+                    "variable names");
     assignment(ls, &nv, nvars+1);
   }
-  else {  /* assignment -> `=' explist1 */
+  else {  /* assignment -> `=' explist */
     int nexps;
     checknext(ls, '=');
-    nexps = explist1(ls, &e);
+    nexps = explist(ls, &e);
     if (nexps != nvars) {
       adjust_assign(ls, nvars, nexps, &e);
       if (nexps > nvars)
@@ -972,19 +1178,44 @@ static int cond (LexState *ls) {
 }
 
 
-static void breakstat (LexState *ls) {
+static void gotostat (LexState *ls, TString *label, int line) {
+  /* create new entry for this goto */
+  int g = newlabelentry(ls, &ls->dyd->gt, label, line, luaK_jump(ls->fs));
+  findlabel(ls, g);
+}
+
+
+/* check for repeated labels on the same block */
+static void checkrepeated (FuncState *fs, Labellist *ll, TString *label) {
+  int i;
+  for (i = fs->bl->firstlabel; i < ll->n; i++) {
+    if (eqstr(label, ll->arr[i].name)) {
+      const char *msg = luaO_pushfstring(fs->ls->L, 
+                          "label " LUA_QS " already defined on line %d",
+                          getstr(label), ll->arr[i].line);
+      semerror(fs->ls, msg);
+    }
+  }
+}
+
+
+static void labelstat (LexState *ls, TString *label, int line) {
+  /* label -> '::' NAME '::' */
   FuncState *fs = ls->fs;
-  BlockCnt *bl = fs->bl;
-  int upval = 0;
-  while (bl && !bl->isbreakable) {
-    upval |= bl->upval;
-    bl = bl->previous;
+  Labellist *ll = &ls->dyd->label;
+  int l;  /* index of new label being created */
+  checkrepeated(fs, ll, label);  /* check for repeated labels */
+  checknext(ls, TK_DBCOLON);  /* skip double colon */
+  /* create new entry for this label */
+  l = newlabelentry(ls, ll, label, line, fs->pc);
+  /* skip other no-op statements */
+  while (ls->t.token == ';' || ls->t.token == TK_DBCOLON)
+    statement(ls);
+  if (block_follow(ls, 0)) {  /* label is last no-op statement in the block? */
+    /* assume that locals are already out of scope */
+    ll->arr[l].nactvar = fs->bl->nactvar;
   }
-  if (!bl)
-    luaX_syntaxerror(ls, "no loop to break");
-  if (upval)
-    luaK_codeABC(fs, OP_CLOSE, bl->nactvar, 0, 0);
-  luaK_concat(fs, &bl->breaklist, luaK_jump(fs));
+  findgotos(ls, &ll->arr[l]);
 }
 
 
@@ -1000,7 +1231,7 @@ static void whilestat (LexState *ls, int line) {
   enterblock(fs, &bl, 1);
   checknext(ls, TK_DO);
   block(ls);
-  luaK_patchlist(fs, luaK_jump(fs), whileinit);
+  luaK_jumpto(fs, whileinit);
   check_match(ls, TK_END, TK_WHILE, line);
   leaveblock(fs);
   luaK_patchtohere(fs, condexit);  /* false conditions finish the loop */
@@ -1016,30 +1247,25 @@ static void repeatstat (LexState *ls, int line) {
   enterblock(fs, &bl1, 1);  /* loop block */
   enterblock(fs, &bl2, 0);  /* scope block */
   luaX_next(ls);  /* skip REPEAT */
-  chunk(ls);
+  statlist(ls);
   check_match(ls, TK_UNTIL, TK_REPEAT, line);
   condexit = cond(ls);  /* read condition (inside scope block) */
-  if (!bl2.upval) {  /* no upvalues? */
-    leaveblock(fs);  /* finish scope */
-    luaK_patchlist(ls->fs, condexit, repeat_init);  /* close the loop */
-  }
-  else {  /* complete semantics when there are upvalues */
-    breakstat(ls);  /* if condition then break */
-    luaK_patchtohere(ls->fs, condexit);  /* else... */
-    leaveblock(fs);  /* finish scope... */
-    luaK_patchlist(ls->fs, luaK_jump(fs), repeat_init);  /* and repeat */
-  }
+  if (bl2.upval)  /* upvalues? */
+    luaK_patchclose(fs, condexit, bl2.nactvar);
+  leaveblock(fs);  /* finish scope */
+  luaK_patchlist(fs, condexit, repeat_init);  /* close the loop */
   leaveblock(fs);  /* finish loop */
 }
 
 
 static int exp1 (LexState *ls) {
   expdesc e;
-  int k;
+  int reg;
   expr(ls, &e);
-  k = e.k;
   luaK_exp2nextreg(ls->fs, &e);
-  return k;
+  lua_assert(e.k == VNONRELOC);
+  reg = e.u.info;
+  return reg;
 }
 
 
@@ -1057,10 +1283,15 @@ static void forbody (LexState *ls, int base, int line, int nvars, int isnum) {
   block(ls);
   leaveblock(fs);  /* end of scope for declared variables */
   luaK_patchtohere(fs, prep);
-  endfor = (isnum) ? luaK_codeAsBx(fs, OP_FORLOOP, base, NO_JUMP) :
-                     luaK_codeABC(fs, OP_TFORLOOP, base, 0, nvars);
-  luaK_fixline(fs, line);  /* pretend that `OP_FOR' starts the loop */
-  luaK_patchlist(fs, (isnum ? endfor : luaK_jump(fs)), prep + 1);
+  if (isnum)  /* numeric for? */
+    endfor = luaK_codeAsBx(fs, OP_FORLOOP, base, NO_JUMP);
+  else {  /* generic for */
+    luaK_codeABC(fs, OP_TFORCALL, base, 0, nvars);
+    luaK_fixline(fs, line);
+    endfor = luaK_codeAsBx(fs, OP_TFORLOOP, base + 2, NO_JUMP);
+  }
+  luaK_patchlist(fs, endfor, prep + 1);
+  luaK_fixline(fs, line);
 }
 
 
@@ -1068,10 +1299,10 @@ static void fornum (LexState *ls, TString *varname, int line) {
   /* fornum -> NAME = exp1,exp1[,exp1] forbody */
   FuncState *fs = ls->fs;
   int base = fs->freereg;
-  new_localvarliteral(ls, "(for index)", 0);
-  new_localvarliteral(ls, "(for limit)", 1);
-  new_localvarliteral(ls, "(for step)", 2);
-  new_localvar(ls, varname, 3);
+  new_localvarliteral(ls, "(for index)");
+  new_localvarliteral(ls, "(for limit)");
+  new_localvarliteral(ls, "(for step)");
+  new_localvar(ls, varname);
   checknext(ls, '=');
   exp1(ls);  /* initial value */
   checknext(ls, ',');
@@ -1079,7 +1310,7 @@ static void fornum (LexState *ls, TString *varname, int line) {
   if (testnext(ls, ','))
     exp1(ls);  /* optional step */
   else {  /* default step = 1 */
-    luaK_codeABx(fs, OP_LOADK, fs->freereg, luaK_numberK(fs, 1));
+    luaK_codek(fs, fs->freereg, luaK_numberK(fs, 1));
     luaK_reserveregs(fs, 1);
   }
   forbody(ls, base, line, 1, 1);
@@ -1087,23 +1318,25 @@ static void fornum (LexState *ls, TString *varname, int line) {
 
 
 static void forlist (LexState *ls, TString *indexname) {
-  /* forlist -> NAME {,NAME} IN explist1 forbody */
+  /* forlist -> NAME {,NAME} IN explist forbody */
   FuncState *fs = ls->fs;
   expdesc e;
-  int nvars = 0;
+  int nvars = 4;  /* gen, state, control, plus at least one declared var */
   int line;
   int base = fs->freereg;
   /* create control variables */
-  new_localvarliteral(ls, "(for generator)", nvars++);
-  new_localvarliteral(ls, "(for state)", nvars++);
-  new_localvarliteral(ls, "(for control)", nvars++);
+  new_localvarliteral(ls, "(for generator)");
+  new_localvarliteral(ls, "(for state)");
+  new_localvarliteral(ls, "(for control)");
   /* create declared variables */
-  new_localvar(ls, indexname, nvars++);
-  while (testnext(ls, ','))
-    new_localvar(ls, str_checkname(ls), nvars++);
+  new_localvar(ls, indexname);
+  while (testnext(ls, ',')) {
+    new_localvar(ls, str_checkname(ls));
+    nvars++;
+  }
   checknext(ls, TK_IN);
   line = ls->linenumber;
-  adjust_assign(ls, 3, explist1(ls, &e), &e);
+  adjust_assign(ls, 3, explist(ls, &e), &e);
   luaK_checkstack(fs, 3);  /* extra space to call generator */
   forbody(ls, base, line, nvars - 3, 0);
 }
@@ -1163,29 +1396,27 @@ static void ifstat (LexState *ls, int line) {
 
 
 static void localfunc (LexState *ls) {
-  expdesc v, b;
+  expdesc b;
   FuncState *fs = ls->fs;
-  new_localvar(ls, str_checkname(ls), 0);
-  init_exp(&v, VLOCAL, fs->freereg);
-  luaK_reserveregs(fs, 1);
-  adjustlocalvars(ls, 1);
-  body(ls, &b, 0, ls->linenumber);
-  luaK_storevar(fs, &v, &b);
+  new_localvar(ls, str_checkname(ls));  /* new local variable */
+  adjustlocalvars(ls, 1);  /* enter its scope */
+  body(ls, &b, 0, ls->linenumber);  /* function created in next register */
   /* debug information will only see the variable after this point! */
-  getlocvar(fs, fs->nactvar - 1).startpc = fs->pc;
+  getlocvar(fs, b.u.info)->startpc = fs->pc;
 }
 
 
 static void localstat (LexState *ls) {
-  /* stat -> LOCAL NAME {`,' NAME} [`=' explist1] */
+  /* stat -> LOCAL NAME {`,' NAME} [`=' explist] */
   int nvars = 0;
   int nexps;
   expdesc e;
   do {
-    new_localvar(ls, str_checkname(ls), nvars++);
+    new_localvar(ls, str_checkname(ls));
+    nvars++;
   } while (testnext(ls, ','));
   if (testnext(ls, '='))
-    nexps = explist1(ls, &e);
+    nexps = explist(ls, &e);
   else {
     e.k = VVOID;
     nexps = 0;
@@ -1196,26 +1427,26 @@ static void localstat (LexState *ls) {
 
 
 static int funcname (LexState *ls, expdesc *v) {
-  /* funcname -> NAME {field} [`:' NAME] */
-  int needself = 0;
+  /* funcname -> NAME {fieldsel} [`:' NAME] */
+  int ismethod = 0;
   singlevar(ls, v);
   while (ls->t.token == '.')
-    field(ls, v);
+    fieldsel(ls, v);
   if (ls->t.token == ':') {
-    needself = 1;
-    field(ls, v);
+    ismethod = 1;
+    fieldsel(ls, v);
   }
-  return needself;
+  return ismethod;
 }
 
 
 static void funcstat (LexState *ls, int line) {
   /* funcstat -> FUNCTION funcname body */
-  int needself;
+  int ismethod;
   expdesc v, b;
   luaX_next(ls);  /* skip FUNCTION */
-  needself = funcname(ls, &v);
-  body(ls, &b, needself, line);
+  ismethod = funcname(ls, &v);
+  body(ls, &b, ismethod, line);
   luaK_storevar(ls->fs, &v, &b);
   luaK_fixline(ls->fs, line);  /* definition `happens' in the first line */
 }
@@ -1236,15 +1467,14 @@ static void exprstat (LexState *ls) {
 
 
 static void retstat (LexState *ls) {
-  /* stat -> RETURN explist */
+  /* stat -> RETURN [explist] [';'] */
   FuncState *fs = ls->fs;
   expdesc e;
   int first, nret;  /* registers with returned values */
-  luaX_next(ls);  /* skip RETURN */
-  if (block_follow(ls->t.token) || ls->t.token == ';')
+  if (block_follow(ls, 1) || ls->t.token == ';')
     first = nret = 0;  /* return no values */
   else {
-    nret = explist1(ls, &e);  /* optional return values */
+    nret = explist(ls, &e);  /* optional return values */
     if (hasmultret(e.k)) {
       luaK_setmultret(fs, &e);
       if (e.k == VCALL && nret == 1) {  /* tail call? */
@@ -1265,37 +1495,43 @@ static void retstat (LexState *ls) {
     }
   }
   luaK_ret(fs, first, nret);
+  testnext(ls, ';');  /* skip optional semicolon */
 }
 
 
-static int statement (LexState *ls) {
+static void statement (LexState *ls) {
   int line = ls->linenumber;  /* may be needed for error messages */
+  enterlevel(ls);
   switch (ls->t.token) {
+    case ';': {  /* stat -> ';' (empty statement) */
+      luaX_next(ls);  /* skip ';' */
+      break;
+    }
     case TK_IF: {  /* stat -> ifstat */
       ifstat(ls, line);
-      return 0;
+      break;
     }
     case TK_WHILE: {  /* stat -> whilestat */
       whilestat(ls, line);
-      return 0;
+      break;
     }
     case TK_DO: {  /* stat -> DO block END */
       luaX_next(ls);  /* skip DO */
       block(ls);
       check_match(ls, TK_END, TK_DO, line);
-      return 0;
+      break;
     }
     case TK_FOR: {  /* stat -> forstat */
       forstat(ls, line);
-      return 0;
+      break;
     }
     case TK_REPEAT: {  /* stat -> repeatstat */
       repeatstat(ls, line);
-      return 0;
+      break;
     }
-    case TK_FUNCTION: {
-      funcstat(ls, line);  /* stat -> funcstat */
-      return 0;
+    case TK_FUNCTION: {  /* stat -> funcstat */
+      funcstat(ls, line);
+      break;
     }
     case TK_LOCAL: {  /* stat -> localstat */
       luaX_next(ls);  /* skip LOCAL */
@@ -1303,37 +1539,64 @@ static int statement (LexState *ls) {
         localfunc(ls);
       else
         localstat(ls);
-      return 0;
+      break;
+    }
+    case TK_DBCOLON: {  /* stat -> label */
+      luaX_next(ls);  /* skip double colon */
+      labelstat(ls, str_checkname(ls), line);
+      break;
     }
     case TK_RETURN: {  /* stat -> retstat */
+      luaX_next(ls);  /* skip RETURN */
       retstat(ls);
-      return 1;  /* must be last statement */
+      break;
     }
     case TK_BREAK: {  /* stat -> breakstat */
       luaX_next(ls);  /* skip BREAK */
-      breakstat(ls);
-      return 1;  /* must be last statement */
+      /* code it as "goto 'break'" */
+      gotostat(ls, luaS_new(ls->L, "break"), line);
+      break;
     }
-    default: {
+    case TK_GOTO: {  /* stat -> 'goto' NAME */
+      luaX_next(ls);  /* skip GOTO */
+      gotostat(ls, str_checkname(ls), line);
+      break;
+    }
+    default: {  /* stat -> func | assignment */
       exprstat(ls);
-      return 0;  /* to avoid warnings */
+      break;
     }
   }
+  lua_assert(ls->fs->f->maxstacksize >= ls->fs->freereg &&
+             ls->fs->freereg >= ls->fs->nactvar);
+  ls->fs->freereg = ls->fs->nactvar;  /* free registers */
+  leavelevel(ls);
 }
 
+/* }====================================================================== */
+
 
-static void chunk (LexState *ls) {
-  /* chunk -> { stat [`;'] } */
-  int islast = 0;
-  enterlevel(ls);
-  while (!islast && !block_follow(ls->t.token)) {
-    islast = statement(ls);
-    testnext(ls, ';');
-    lua_assert(ls->fs->f->maxstacksize >= ls->fs->freereg &&
-               ls->fs->freereg >= ls->fs->nactvar);
-    ls->fs->freereg = ls->fs->nactvar;  /* free registers */
-  }
-  leavelevel(ls);
+Proto *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff,
+                    Dyndata *dyd, const char *name, int firstchar) {
+  LexState lexstate;
+  FuncState funcstate;
+  BlockCnt bl;
+  TString *tname = luaS_new(L, name);
+  setsvalue2s(L, L->top, tname);  /* push name to protect it */
+  incr_top(L);
+  lexstate.buff = buff;
+  lexstate.dyd = dyd;
+  dyd->actvar.n = dyd->gt.n = dyd->label.n = 0;
+  luaX_setinput(L, &lexstate, z, tname, firstchar);
+  open_mainfunc(&lexstate, &funcstate, &bl);
+  luaX_next(&lexstate);  /* read first token */
+  statlist(&lexstate);  /* main body */
+  check(&lexstate, TK_EOS);
+  close_func(&lexstate);
+  L->top--;  /* pop name */
+  lua_assert(!funcstate.prev && funcstate.nups == 1 && !lexstate.fs);
+  return funcstate.f;
+  /* all scopes should be correctly finished */
+  lua_assert(dyd->actvar.n == 0 && dyd->gt.n == 0 && dyd->label.n == 0);
 }
 
-/* }====================================================================== */
diff --git a/src/lparser.h b/src/lparser.h
index 18836af..4e7e06f 100644..100755
--- a/src/lparser.h
+++ b/src/lparser.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lparser.h,v 1.57.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lparser.h,v 1.68 2011/02/23 13:13:10 roberto Exp $
 ** Lua Parser
 ** See Copyright Notice in lua.h
 */
@@ -23,34 +23,72 @@ typedef enum {
   VFALSE,
   VK,		/* info = index of constant in `k' */
   VKNUM,	/* nval = numerical value */
+  VNONRELOC,	/* info = result register */
   VLOCAL,	/* info = local register */
-  VUPVAL,       /* info = index of upvalue in `upvalues' */
-  VGLOBAL,	/* info = index of table; aux = index of global name in `k' */
-  VINDEXED,	/* info = table register; aux = index register (or `k') */
+  VUPVAL,       /* info = index of upvalue in 'upvalues' */
+  VINDEXED,	/* t = table register/upvalue; idx = index R/K */
   VJMP,		/* info = instruction pc */
   VRELOCABLE,	/* info = instruction pc */
-  VNONRELOC,	/* info = result register */
   VCALL,	/* info = instruction pc */
   VVARARG	/* info = instruction pc */
 } expkind;
 
+
+#define vkisvar(k)	(VLOCAL <= (k) && (k) <= VINDEXED)
+#define vkisinreg(k)	((k) == VNONRELOC || (k) == VLOCAL)
+
 typedef struct expdesc {
   expkind k;
   union {
-    struct { int info, aux; } s;
-    lua_Number nval;
+    struct {  /* for indexed variables (VINDEXED) */
+      short idx;  /* index (R/K) */
+      lu_byte t;  /* table (register or upvalue) */
+      lu_byte vt;  /* whether 't' is register (VLOCAL) or upvalue (VUPVAL) */
+    } ind;
+    int info;  /* for generic use */
+    lua_Number nval;  /* for VKNUM */
   } u;
   int t;  /* patch list of `exit when true' */
   int f;  /* patch list of `exit when false' */
 } expdesc;
 
 
-typedef struct upvaldesc {
-  lu_byte k;
-  lu_byte info;
-} upvaldesc;
+/* description of active local variable */
+typedef struct Vardesc {
+  unsigned short idx;  /* variable index in stack */
+} Vardesc;
+
+
+/* description of pending goto statements and label statements */
+typedef struct Labeldesc {
+  TString *name;  /* label identifier */
+  int pc;  /* position in code */
+  int line;  /* line where it appeared */
+  lu_byte nactvar;  /* local level where it appears in current block */
+} Labeldesc;
+
+
+/* list of labels or gotos */
+typedef struct Labellist {
+  Labeldesc *arr;  /* array */
+  int n;  /* number of entries in use */
+  int size;  /* array size */
+} Labellist;
+
+
+/* dynamic structures used by the parser */
+typedef struct Dyndata {
+  struct {  /* list of active local variables */
+    Vardesc *arr;
+    int n;
+    int size;
+  } actvar;
+  Labellist gt;  /* list of pending gotos */
+  Labellist label;   /* list of active labels */
+} Dyndata;
 
 
+/* control of blocks */
 struct BlockCnt;  /* defined in lparser.c */
 
 
@@ -68,15 +106,15 @@ typedef struct FuncState {
   int freereg;  /* first free register */
   int nk;  /* number of elements in `k' */
   int np;  /* number of elements in `p' */
+  int firstlocal;  /* index of first local var of this function */
   short nlocvars;  /* number of elements in `locvars' */
   lu_byte nactvar;  /* number of active local variables */
-  upvaldesc upvalues[LUAI_MAXUPVALUES];  /* upvalues */
-  unsigned short actvar[LUAI_MAXVARS];  /* declared-variable stack */
+  lu_byte nups;  /* number of upvalues */
 } FuncState;
 
 
 LUAI_FUNC Proto *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff,
-                                            const char *name);
+                              Dyndata *dyd, const char *name, int firstchar);
 
 
 #endif
diff --git a/src/lstate.c b/src/lstate.c
index 4313b83..45dac3c 100644..100755
--- a/src/lstate.c
+++ b/src/lstate.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lstate.c,v 2.36.1.2 2008/01/03 15:20:39 roberto Exp $
+** $Id: lstate.c,v 2.89 2010/12/20 19:40:07 roberto Exp $
 ** Global State
 ** See Copyright Notice in lua.h
 */
@@ -12,6 +12,7 @@
 
 #include "lua.h"
 
+#include "lapi.h"
 #include "ldebug.h"
 #include "ldo.h"
 #include "lfunc.h"
@@ -24,66 +25,150 @@
 #include "ltm.h"
 
 
-#define state_size(x)	(sizeof(x) + LUAI_EXTRASPACE)
-#define fromstate(l)	(cast(lu_byte *, (l)) - LUAI_EXTRASPACE)
-#define tostate(l)   (cast(lua_State *, cast(lu_byte *, l) + LUAI_EXTRASPACE))
+#if !defined(LUAI_GCPAUSE)
+#define LUAI_GCPAUSE	200  /* 200% */
+#endif
+
+#if !defined(LUAI_GCMAJOR)
+#define LUAI_GCMAJOR	200  /* 200% */
+#endif
+
+#if !defined(LUAI_GCMUL)
+#define LUAI_GCMUL	200 /* GC runs 'twice the speed' of memory allocation */
+#endif
+
+
+#define MEMERRMSG       "not enough memory"
+
+
+/*
+** thread state + extra space
+*/
+typedef struct LX {
+#if defined(LUAI_EXTRASPACE)
+  char buff[LUAI_EXTRASPACE];
+#endif
+  lua_State l;
+} LX;
 
 
 /*
 ** Main thread combines a thread state and the global state
 */
 typedef struct LG {
-  lua_State l;
+  LX l;
   global_State g;
 } LG;
-  
+
+
+
+#define fromstate(L)	(cast(LX *, cast(lu_byte *, (L)) - offsetof(LX, l)))
+
+
+/*
+** set GCdebt to a new value keeping the value (totalbytes + GCdebt)
+** invariant
+*/
+void luaE_setdebt (global_State *g, l_mem debt) {
+  g->totalbytes -= (debt - g->GCdebt);
+  g->GCdebt = debt;
+}
+
+
+CallInfo *luaE_extendCI (lua_State *L) {
+  CallInfo *ci = luaM_new(L, CallInfo);
+  lua_assert(L->ci->next == NULL);
+  L->ci->next = ci;
+  ci->previous = L->ci;
+  ci->next = NULL;
+  return ci;
+}
+
+
+void luaE_freeCI (lua_State *L) {
+  CallInfo *ci = L->ci;
+  CallInfo *next = ci->next;
+  ci->next = NULL;
+  while ((ci = next) != NULL) {
+    next = ci->next;
+    luaM_free(L, ci);
+  }
+}
 
 
 static void stack_init (lua_State *L1, lua_State *L) {
-  /* initialize CallInfo array */
-  L1->base_ci = luaM_newvector(L, BASIC_CI_SIZE, CallInfo);
-  L1->ci = L1->base_ci;
-  L1->size_ci = BASIC_CI_SIZE;
-  L1->end_ci = L1->base_ci + L1->size_ci - 1;
+  int i; CallInfo *ci;
   /* initialize stack array */
-  L1->stack = luaM_newvector(L, BASIC_STACK_SIZE + EXTRA_STACK, TValue);
-  L1->stacksize = BASIC_STACK_SIZE + EXTRA_STACK;
+  L1->stack = luaM_newvector(L, BASIC_STACK_SIZE, TValue);
+  L1->stacksize = BASIC_STACK_SIZE;
+  for (i = 0; i < BASIC_STACK_SIZE; i++)
+    setnilvalue(L1->stack + i);  /* erase new stack */
   L1->top = L1->stack;
-  L1->stack_last = L1->stack+(L1->stacksize - EXTRA_STACK)-1;
+  L1->stack_last = L1->stack + L1->stacksize - EXTRA_STACK;
   /* initialize first ci */
-  L1->ci->func = L1->top;
-  setnilvalue(L1->top++);  /* `function' entry for this `ci' */
-  L1->base = L1->ci->base = L1->top;
-  L1->ci->top = L1->top + LUA_MINSTACK;
+  ci = &L1->base_ci;
+  ci->next = ci->previous = NULL;
+  ci->callstatus = 0;
+  ci->func = L1->top;
+  setnilvalue(L1->top++);  /* 'function' entry for this 'ci' */
+  ci->top = L1->top + LUA_MINSTACK;
+  L1->ci = ci;
 }
 
 
-static void freestack (lua_State *L, lua_State *L1) {
-  luaM_freearray(L, L1->base_ci, L1->size_ci, CallInfo);
-  luaM_freearray(L, L1->stack, L1->stacksize, TValue);
+static void freestack (lua_State *L) {
+  if (L->stack == NULL)
+    return;  /* stack not completely built yet */
+  L->ci = &L->base_ci;  /* free the entire 'ci' list */
+  luaE_freeCI(L);
+  luaM_freearray(L, L->stack, L->stacksize);  /* free stack array */
+}
+
+
+/*
+** Create registry table and its predefined values
+*/
+static void init_registry (lua_State *L, global_State *g) {
+  TValue mt;
+  /* create registry */
+  Table *registry = luaH_new(L);
+  sethvalue(L, &g->l_registry, registry);
+  luaH_resize(L, registry, LUA_RIDX_LAST, 0);
+  /* registry[LUA_RIDX_MAINTHREAD] = L */
+  setthvalue(L, &mt, L);
+  setobj2t(L, luaH_setint(L, registry, LUA_RIDX_MAINTHREAD), &mt);
+  /* registry[LUA_RIDX_GLOBALS] = table of globals */
+  sethvalue(L, &mt, luaH_new(L));
+  setobj2t(L, luaH_setint(L, registry, LUA_RIDX_GLOBALS), &mt);
 }
 
 
 /*
-** open parts that may cause memory-allocation errors
+** open parts of the state that may cause memory-allocation errors
 */
 static void f_luaopen (lua_State *L, void *ud) {
   global_State *g = G(L);
   UNUSED(ud);
   stack_init(L, L);  /* init stack */
-  sethvalue(L, gt(L), luaH_new(L, 0, 2));  /* table of globals */
-  sethvalue(L, registry(L), luaH_new(L, 0, 2));  /* registry */
+  init_registry(L, g);
   luaS_resize(L, MINSTRTABSIZE);  /* initial size of string table */
   luaT_init(L);
   luaX_init(L);
-  luaS_fix(luaS_newliteral(L, MEMERRMSG));
-  g->GCthreshold = 4*g->totalbytes;
+  /* pre-create memory-error message */
+  g->memerrmsg = luaS_newliteral(L, MEMERRMSG);
+  luaS_fix(g->memerrmsg);  /* it should never be collected */
+  g->gcrunning = 1;  /* allow gc */
 }
 
 
+/*
+** preinitialize a state with consistent values without allocating
+** any memory (to avoid errors)
+*/
 static void preinit_state (lua_State *L, global_State *g) {
   G(L) = g;
   L->stack = NULL;
+  L->ci = NULL;
   L->stacksize = 0;
   L->errorJmp = NULL;
   L->hook = NULL;
@@ -92,51 +177,50 @@ static void preinit_state (lua_State *L, global_State *g) {
   L->allowhook = 1;
   resethookcount(L);
   L->openupval = NULL;
-  L->size_ci = 0;
-  L->nCcalls = L->baseCcalls = 0;
-  L->status = 0;
-  L->base_ci = L->ci = NULL;
-  L->savedpc = NULL;
+  L->nny = 1;
+  L->status = LUA_OK;
   L->errfunc = 0;
-  setnilvalue(gt(L));
 }
 
 
 static void close_state (lua_State *L) {
   global_State *g = G(L);
   luaF_close(L, L->stack);  /* close all upvalues for this thread */
-  luaC_freeall(L);  /* collect all objects */
-  lua_assert(g->rootgc == obj2gco(L));
-  lua_assert(g->strt.nuse == 0);
-  luaM_freearray(L, G(L)->strt.hash, G(L)->strt.size, TString *);
+  luaC_freeallobjects(L);  /* collect all objects */
+  luaM_freearray(L, G(L)->strt.hash, G(L)->strt.size);
   luaZ_freebuffer(L, &g->buff);
-  freestack(L, L);
-  lua_assert(g->totalbytes == sizeof(LG));
-  (*g->frealloc)(g->ud, fromstate(L), state_size(LG), 0);
+  freestack(L);
+  lua_assert(gettotalbytes(g) == sizeof(LG));
+  (*g->frealloc)(g->ud, fromstate(L), sizeof(LG), 0);
 }
 
 
-lua_State *luaE_newthread (lua_State *L) {
-  lua_State *L1 = tostate(luaM_malloc(L, state_size(lua_State)));
-  luaC_link(L, obj2gco(L1), LUA_TTHREAD);
+LUA_API lua_State *lua_newthread (lua_State *L) {
+  lua_State *L1;
+  lua_lock(L);
+  luaC_checkGC(L);
+  L1 = &luaC_newobj(L, LUA_TTHREAD, sizeof(LX), NULL, offsetof(LX, l))->th;
+  setthvalue(L, L->top, L1);
+  api_incr_top(L);
   preinit_state(L1, G(L));
-  stack_init(L1, L);  /* init stack */
-  setobj2n(L, gt(L1), gt(L));  /* share table of globals */
   L1->hookmask = L->hookmask;
   L1->basehookcount = L->basehookcount;
   L1->hook = L->hook;
   resethookcount(L1);
-  lua_assert(iswhite(obj2gco(L1)));
+  luai_userstatethread(L, L1);
+  stack_init(L1, L);  /* init stack */
+  lua_unlock(L);
   return L1;
 }
 
 
 void luaE_freethread (lua_State *L, lua_State *L1) {
+  LX *l = fromstate(L1);
   luaF_close(L1, L1->stack);  /* close all upvalues for this thread */
   lua_assert(L1->openupval == NULL);
-  luai_userstatefree(L1);
-  freestack(L, L1);
-  luaM_freemem(L, fromstate(L1), state_size(lua_State));
+  luai_userstatefree(L, L1);
+  freestack(L1);
+  luaM_free(L, l);
 }
 
 
@@ -144,42 +228,44 @@ LUA_API lua_State *lua_newstate (lua_Alloc f, void *ud) {
   int i;
   lua_State *L;
   global_State *g;
-  void *l = (*f)(ud, NULL, 0, state_size(LG));
+  LG *l = cast(LG *, (*f)(ud, NULL, LUA_TTHREAD, sizeof(LG)));
   if (l == NULL) return NULL;
-  L = tostate(l);
-  g = &((LG *)L)->g;
+  L = &l->l.l;
+  g = &l->g;
   L->next = NULL;
   L->tt = LUA_TTHREAD;
   g->currentwhite = bit2mask(WHITE0BIT, FIXEDBIT);
   L->marked = luaC_white(g);
-  set2bits(L->marked, FIXEDBIT, SFIXEDBIT);
+  g->gckind = KGC_NORMAL;
+  g->nCcalls = 0;
   preinit_state(L, g);
   g->frealloc = f;
   g->ud = ud;
   g->mainthread = L;
   g->uvhead.u.l.prev = &g->uvhead;
   g->uvhead.u.l.next = &g->uvhead;
-  g->GCthreshold = 0;  /* mark it as unfinished state */
+  g->gcrunning = 0;  /* no GC while building state */
+  g->lastmajormem = 0;
   g->strt.size = 0;
   g->strt.nuse = 0;
   g->strt.hash = NULL;
-  setnilvalue(registry(L));
+  setnilvalue(&g->l_registry);
   luaZ_initbuffer(L, &g->buff);
   g->panic = NULL;
+  g->version = lua_version(NULL);
   g->gcstate = GCSpause;
-  g->rootgc = obj2gco(L);
-  g->sweepstrgc = 0;
-  g->sweepgc = &g->rootgc;
-  g->gray = NULL;
-  g->grayagain = NULL;
-  g->weak = NULL;
-  g->tmudata = NULL;
+  g->allgc = NULL;
+  g->finobj = NULL;
+  g->tobefnz = NULL;
+  g->gray = g->grayagain = NULL;
+  g->weak = g->ephemeron = g->allweak = NULL;
   g->totalbytes = sizeof(LG);
+  g->GCdebt = 0;
   g->gcpause = LUAI_GCPAUSE;
+  g->gcmajorinc = LUAI_GCMAJOR;
   g->gcstepmul = LUAI_GCMUL;
-  g->gcdept = 0;
-  for (i=0; i<NUM_TAGS; i++) g->mt[i] = NULL;
-  if (luaD_rawrunprotected(L, f_luaopen, NULL) != 0) {
+  for (i=0; i < LUA_NUMTAGS; i++) g->mt[i] = NULL;
+  if (luaD_rawrunprotected(L, f_luaopen, NULL) != LUA_OK) {
     /* memory allocation error: free partial state */
     close_state(L);
     L = NULL;
@@ -190,25 +276,14 @@ LUA_API lua_State *lua_newstate (lua_Alloc f, void *ud) {
 }
 
 
-static void callallgcTM (lua_State *L, void *ud) {
-  UNUSED(ud);
-  luaC_callGCTM(L);  /* call GC metamethods for all udata */
-}
-
-
 LUA_API void lua_close (lua_State *L) {
   L = G(L)->mainthread;  /* only the main thread can be closed */
   lua_lock(L);
   luaF_close(L, L->stack);  /* close all upvalues for this thread */
-  luaC_separateudata(L, 1);  /* separate udata that have GC metamethods */
-  L->errfunc = 0;  /* no error function during GC metamethods */
-  do {  /* repeat until no more errors */
-    L->ci = L->base_ci;
-    L->base = L->top = L->ci->base;
-    L->nCcalls = L->baseCcalls = 0;
-  } while (luaD_rawrunprotected(L, callallgcTM, NULL) != 0);
-  lua_assert(G(L)->tmudata == NULL);
+  luaC_separateudata(L, 1);  /* separate all udata with GC metamethods */
+  lua_assert(L->next == NULL);
   luai_userstateclose(L);
   close_state(L);
 }
 
+
diff --git a/src/lstate.h b/src/lstate.h
index 3bc575b..9d21e7e 100644..100755
--- a/src/lstate.h
+++ b/src/lstate.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lstate.h,v 2.24.1.2 2008/01/03 15:20:39 roberto Exp $
+** $Id: lstate.h,v 2.72 2011/06/02 19:31:40 roberto Exp $
 ** Global State
 ** See Copyright Notice in lua.h
 */
@@ -14,15 +14,33 @@
 #include "lzio.h"
 
 
+/*
 
-struct lua_longjmp;  /* defined in ldo.c */
+** Some notes about garbage-collected objects:  All objects in Lua must
+** be kept somehow accessible until being freed.
+**
+** Lua keeps most objects linked in list g->allgc. The link uses field
+** 'next' of the CommonHeader.
+**
+** Strings are kept in several lists headed by the array g->strt.hash.
+**
+** Open upvalues are not subject to independent garbage collection. They
+** are collected together with their respective threads. Lua keeps a
+** double-linked list with all open upvalues (g->uvhead) so that it can
+** mark objects referred by them. (They are always gray, so they must
+** be remarked in the atomic step. Usually their contents would be marked
+** when traversing the respective threads, but the thread may already be
+** dead, while the upvalue is still accessible through closures.)
+**
+** Objects with finalizers are kept in the list g->finobj.
+**
+** The list g->tobefnz links all objects being finalized.
 
+*/
 
-/* table of globals */
-#define gt(L)	(&L->l_gt)
 
-/* registry */
-#define registry(L)	(&G(L)->l_registry)
+struct lua_longjmp;  /* defined in ldo.c */
+
 
 
 /* extra stack space to handle TM calls and some other extras */
@@ -34,6 +52,11 @@ struct lua_longjmp;  /* defined in ldo.c */
 #define BASIC_STACK_SIZE        (2*LUA_MINSTACK)
 
 
+/* kinds of Garbage Collection */
+#define KGC_NORMAL	0
+#define KGC_EMERGENCY	1	/* gc was forced by an allocation failure */
+#define KGC_GEN		2	/* generational collection */
+
 
 typedef struct stringtable {
   GCObject **hash;
@@ -43,54 +66,84 @@ typedef struct stringtable {
 
 
 /*
-** informations about a call
+** information about a call
 */
 typedef struct CallInfo {
-  StkId base;  /* base for this function */
   StkId func;  /* function index in the stack */
   StkId	top;  /* top for this function */
-  const Instruction *savedpc;
-  int nresults;  /* expected number of results from this function */
-  int tailcalls;  /* number of tail calls lost under this entry */
+  struct CallInfo *previous, *next;  /* dynamic call link */
+  short nresults;  /* expected number of results from this function */
+  lu_byte callstatus;
+  union {
+    struct {  /* only for Lua functions */
+      StkId base;  /* base for this function */
+      const Instruction *savedpc;
+    } l;
+    struct {  /* only for C functions */
+      int ctx;  /* context info. in case of yields */
+      lua_CFunction k;  /* continuation in case of yields */
+      ptrdiff_t old_errfunc;
+      ptrdiff_t extra;
+      lu_byte old_allowhook;
+      lu_byte status;
+    } c;
+  } u;
 } CallInfo;
 
 
+/*
+** Bits in CallInfo status
+*/
+#define CIST_LUA	(1<<0)	/* call is running a Lua function */
+#define CIST_HOOKED	(1<<1)	/* call is running a debug hook */
+#define CIST_REENTRY	(1<<2)	/* call is running on same invocation of
+                                   luaV_execute of previous call */
+#define CIST_YIELDED	(1<<3)	/* call reentered after suspension */
+#define CIST_YPCALL	(1<<4)	/* call is a yieldable protected call */
+#define CIST_STAT	(1<<5)	/* call has an error status (pcall) */
+#define CIST_TAIL	(1<<6)	/* call was tail called */
 
-#define curr_func(L)	(clvalue(L->ci->func))
-#define ci_func(ci)	(clvalue((ci)->func))
-#define f_isLua(ci)	(!ci_func(ci)->c.isC)
-#define isLua(ci)	(ttisfunction((ci)->func) && f_isLua(ci))
+
+#define isLua(ci)	((ci)->callstatus & CIST_LUA)
 
 
 /*
 ** `global state', shared by all threads of this state
 */
 typedef struct global_State {
-  stringtable strt;  /* hash table for strings */
   lua_Alloc frealloc;  /* function to reallocate memory */
   void *ud;         /* auxiliary data to `frealloc' */
+  lu_mem totalbytes;  /* number of bytes currently allocated - GCdebt */
+  l_mem GCdebt;  /* bytes allocated not yet compensated by the collector */
+  lu_mem lastmajormem;  /* memory in use after last major collection */
+  stringtable strt;  /* hash table for strings */
+  TValue l_registry;
+  unsigned short nCcalls;  /* number of nested C calls */
   lu_byte currentwhite;
   lu_byte gcstate;  /* state of garbage collector */
+  lu_byte gckind;  /* kind of GC running */
+  lu_byte gcrunning;  /* true if GC is running */
   int sweepstrgc;  /* position of sweep in `strt' */
-  GCObject *rootgc;  /* list of all collectable objects */
-  GCObject **sweepgc;  /* position of sweep in `rootgc' */
+  GCObject *allgc;  /* list of all collectable objects */
+  GCObject *finobj;  /* list of collectable objects with finalizers */
+  GCObject **sweepgc;  /* current position of sweep */
   GCObject *gray;  /* list of gray objects */
   GCObject *grayagain;  /* list of objects to be traversed atomically */
-  GCObject *weak;  /* list of weak tables (to be cleared) */
-  GCObject *tmudata;  /* last element of list of userdata to be GC */
-  Mbuffer buff;  /* temporary buffer for string concatentation */
-  lu_mem GCthreshold;
-  lu_mem totalbytes;  /* number of bytes currently allocated */
-  lu_mem estimate;  /* an estimate of number of bytes actually in use */
-  lu_mem gcdept;  /* how much GC is `behind schedule' */
+  GCObject *weak;  /* list of tables with weak values */
+  GCObject *ephemeron;  /* list of ephemeron tables (weak keys) */
+  GCObject *allweak;  /* list of all-weak tables */
+  GCObject *tobefnz;  /* list of userdata to be GC */
+  UpVal uvhead;  /* head of double-linked list of all open upvalues */
+  Mbuffer buff;  /* temporary buffer for string concatenation */
   int gcpause;  /* size of pause between successive GCs */
+  int gcmajorinc;  /* how much to wait for a major GC (only in gen. mode) */
   int gcstepmul;  /* GC `granularity' */
   lua_CFunction panic;  /* to be called in unprotected errors */
-  TValue l_registry;
   struct lua_State *mainthread;
-  UpVal uvhead;  /* head of double-linked list of all open upvalues */
-  struct Table *mt[NUM_TAGS];  /* metatables for basic types */
+  const lua_Number *version;  /* pointer to version number */
+  TString *memerrmsg;  /* memory-error message */
   TString *tmname[TM_N];  /* array with tag-method names */
+  struct Table *mt[LUA_NUMTAGS];  /* metatables for basic types */
 } global_State;
 
 
@@ -101,29 +154,23 @@ struct lua_State {
   CommonHeader;
   lu_byte status;
   StkId top;  /* first free slot in the stack */
-  StkId base;  /* base of current function */
   global_State *l_G;
   CallInfo *ci;  /* call info for current function */
-  const Instruction *savedpc;  /* `savedpc' of current function */
+  const Instruction *oldpc;  /* last pc traced */
   StkId stack_last;  /* last free slot in the stack */
   StkId stack;  /* stack base */
-  CallInfo *end_ci;  /* points after end of ci array*/
-  CallInfo *base_ci;  /* array of CallInfo's */
   int stacksize;
-  int size_ci;  /* size of array `base_ci' */
-  unsigned short nCcalls;  /* number of nested C calls */
-  unsigned short baseCcalls;  /* nested C calls when resuming coroutine */
+  unsigned short nny;  /* number of non-yieldable calls in stack */
   lu_byte hookmask;
   lu_byte allowhook;
   int basehookcount;
   int hookcount;
   lua_Hook hook;
-  TValue l_gt;  /* table of globals */
-  TValue env;  /* temporary place for environments */
   GCObject *openupval;  /* list of open upvalues in this stack */
   GCObject *gclist;
   struct lua_longjmp *errorJmp;  /* current error recover point */
   ptrdiff_t errfunc;  /* current error handling function (stack index) */
+  CallInfo base_ci;  /* CallInfo for first level (C calling Lua) */
 };
 
 
@@ -134,7 +181,7 @@ struct lua_State {
 ** Union of all collectable objects
 */
 union GCObject {
-  GCheader gch;
+  GCheader gch;  /* common header */
   union TString ts;
   union Udata u;
   union Closure cl;
@@ -145,25 +192,31 @@ union GCObject {
 };
 
 
+#define gch(o)		(&(o)->gch)
+
 /* macros to convert a GCObject into a specific value */
 #define rawgco2ts(o)	check_exp((o)->gch.tt == LUA_TSTRING, &((o)->ts))
 #define gco2ts(o)	(&rawgco2ts(o)->tsv)
 #define rawgco2u(o)	check_exp((o)->gch.tt == LUA_TUSERDATA, &((o)->u))
 #define gco2u(o)	(&rawgco2u(o)->uv)
 #define gco2cl(o)	check_exp((o)->gch.tt == LUA_TFUNCTION, &((o)->cl))
-#define gco2h(o)	check_exp((o)->gch.tt == LUA_TTABLE, &((o)->h))
+#define gco2t(o)	check_exp((o)->gch.tt == LUA_TTABLE, &((o)->h))
 #define gco2p(o)	check_exp((o)->gch.tt == LUA_TPROTO, &((o)->p))
 #define gco2uv(o)	check_exp((o)->gch.tt == LUA_TUPVAL, &((o)->uv))
-#define ngcotouv(o) \
-	check_exp((o) == NULL || (o)->gch.tt == LUA_TUPVAL, &((o)->uv))
 #define gco2th(o)	check_exp((o)->gch.tt == LUA_TTHREAD, &((o)->th))
 
 /* macro to convert any Lua object into a GCObject */
 #define obj2gco(v)	(cast(GCObject *, (v)))
 
 
-LUAI_FUNC lua_State *luaE_newthread (lua_State *L);
+/* actual number of total bytes allocated */
+#define gettotalbytes(g)	((g)->totalbytes + (g)->GCdebt)
+
+LUAI_FUNC void luaE_setdebt (global_State *g, l_mem debt);
 LUAI_FUNC void luaE_freethread (lua_State *L, lua_State *L1);
+LUAI_FUNC CallInfo *luaE_extendCI (lua_State *L);
+LUAI_FUNC void luaE_freeCI (lua_State *L);
+
 
 #endif
 
diff --git a/src/lstring.c b/src/lstring.c
index 4911315..adec415 100644..100755
--- a/src/lstring.c
+++ b/src/lstring.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lstring.c,v 2.8.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lstring.c,v 2.19 2011/05/03 16:01:57 roberto Exp $
 ** String table (keeps all strings handled by Lua)
 ** See Copyright Notice in lua.h
 */
@@ -20,54 +20,55 @@
 
 
 void luaS_resize (lua_State *L, int newsize) {
-  GCObject **newhash;
-  stringtable *tb;
   int i;
-  if (G(L)->gcstate == GCSsweepstring)
-    return;  /* cannot resize during GC traverse */
-  newhash = luaM_newvector(L, newsize, GCObject *);
-  tb = &G(L)->strt;
-  for (i=0; i<newsize; i++) newhash[i] = NULL;
+  stringtable *tb = &G(L)->strt;
+  /* cannot resize while GC is traversing strings */
+  luaC_runtilstate(L, ~bitmask(GCSsweepstring));
+  if (newsize > tb->size) {
+    luaM_reallocvector(L, tb->hash, tb->size, newsize, GCObject *);
+    for (i = tb->size; i < newsize; i++) tb->hash[i] = NULL;
+  }
   /* rehash */
   for (i=0; i<tb->size; i++) {
     GCObject *p = tb->hash[i];
+    tb->hash[i] = NULL;
     while (p) {  /* for each node in the list */
-      GCObject *next = p->gch.next;  /* save next */
-      unsigned int h = gco2ts(p)->hash;
-      int h1 = lmod(h, newsize);  /* new position */
-      lua_assert(cast_int(h%newsize) == lmod(h, newsize));
-      p->gch.next = newhash[h1];  /* chain it */
-      newhash[h1] = p;
+      GCObject *next = gch(p)->next;  /* save next */
+      unsigned int h = lmod(gco2ts(p)->hash, newsize);  /* new position */
+      gch(p)->next = tb->hash[h];  /* chain it */
+      tb->hash[h] = p;
+      resetoldbit(p);  /* see MOVE OLD rule */
       p = next;
     }
   }
-  luaM_freearray(L, tb->hash, tb->size, TString *);
+  if (newsize < tb->size) {
+    /* shrinking slice must be empty */
+    lua_assert(tb->hash[newsize] == NULL && tb->hash[tb->size - 1] == NULL);
+    luaM_reallocvector(L, tb->hash, tb->size, newsize, GCObject *);
+  }
   tb->size = newsize;
-  tb->hash = newhash;
 }
 
 
 static TString *newlstr (lua_State *L, const char *str, size_t l,
                                        unsigned int h) {
+  size_t totalsize;  /* total size of TString object */
+  GCObject **list;  /* (pointer to) list where it will be inserted */
   TString *ts;
-  stringtable *tb;
+  stringtable *tb = &G(L)->strt;
   if (l+1 > (MAX_SIZET - sizeof(TString))/sizeof(char))
     luaM_toobig(L);
-  ts = cast(TString *, luaM_malloc(L, (l+1)*sizeof(char)+sizeof(TString)));
+  if (tb->nuse >= cast(lu_int32, tb->size) && tb->size <= MAX_INT/2)
+    luaS_resize(L, tb->size*2);  /* too crowded */
+  totalsize = sizeof(TString) + ((l + 1) * sizeof(char));
+  list = &tb->hash[lmod(h, tb->size)];
+  ts = &luaC_newobj(L, LUA_TSTRING, totalsize, list, 0)->ts;
   ts->tsv.len = l;
   ts->tsv.hash = h;
-  ts->tsv.marked = luaC_white(G(L));
-  ts->tsv.tt = LUA_TSTRING;
   ts->tsv.reserved = 0;
   memcpy(ts+1, str, l*sizeof(char));
   ((char *)(ts+1))[l] = '\0';  /* ending 0 */
-  tb = &G(L)->strt;
-  h = lmod(h, tb->size);
-  ts->tsv.next = tb->hash[h];  /* chain new entry */
-  tb->hash[h] = obj2gco(ts);
   tb->nuse++;
-  if (tb->nuse > cast(lu_int32, tb->size) && tb->size <= MAX_INT/2)
-    luaS_resize(L, tb->size*2);  /* too crowded */
   return ts;
 }
 
@@ -81,15 +82,22 @@ TString *luaS_newlstr (lua_State *L, const char *str, size_t l) {
     h = h ^ ((h<<5)+(h>>2)+cast(unsigned char, str[l1-1]));
   for (o = G(L)->strt.hash[lmod(h, G(L)->strt.size)];
        o != NULL;
-       o = o->gch.next) {
+       o = gch(o)->next) {
     TString *ts = rawgco2ts(o);
-    if (ts->tsv.len == l && (memcmp(str, getstr(ts), l) == 0)) {
-      /* string may be dead */
-      if (isdead(G(L), o)) changewhite(o);
+    if (h == ts->tsv.hash &&
+        ts->tsv.len == l &&
+        (memcmp(str, getstr(ts), l * sizeof(char)) == 0)) {
+      if (isdead(G(L), o))  /* string is dead (but was not collected yet)? */
+        changewhite(o);  /* resurrect it */
       return ts;
     }
   }
-  return newlstr(L, str, l, h);  /* not found */
+  return newlstr(L, str, l, h);  /* not found; create a new string */
+}
+
+
+TString *luaS_new (lua_State *L, const char *str) {
+  return luaS_newlstr(L, str, strlen(str));
 }
 
 
@@ -97,15 +105,10 @@ Udata *luaS_newudata (lua_State *L, size_t s, Table *e) {
   Udata *u;
   if (s > MAX_SIZET - sizeof(Udata))
     luaM_toobig(L);
-  u = cast(Udata *, luaM_malloc(L, s + sizeof(Udata)));
-  u->uv.marked = luaC_white(G(L));  /* is not finalized */
-  u->uv.tt = LUA_TUSERDATA;
+  u = &luaC_newobj(L, LUA_TUSERDATA, sizeof(Udata) + s, NULL, 0)->u;
   u->uv.len = s;
   u->uv.metatable = NULL;
   u->uv.env = e;
-  /* chain it on udata list (after main thread) */
-  u->uv.next = G(L)->mainthread->next;
-  G(L)->mainthread->next = obj2gco(u);
   return u;
 }
 
diff --git a/src/lstring.h b/src/lstring.h
index 73a2ff8..d708a1b 100644..100755
--- a/src/lstring.h
+++ b/src/lstring.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lstring.h,v 1.43.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lstring.h,v 1.46 2010/04/05 16:26:37 roberto Exp $
 ** String table (keep all strings handled by Lua)
 ** See Copyright Notice in lua.h
 */
@@ -7,7 +7,6 @@
 #ifndef lstring_h
 #define lstring_h
 
-
 #include "lgc.h"
 #include "lobject.h"
 #include "lstate.h"
@@ -17,15 +16,22 @@
 
 #define sizeudata(u)	(sizeof(union Udata)+(u)->len)
 
-#define luaS_new(L, s)	(luaS_newlstr(L, s, strlen(s)))
 #define luaS_newliteral(L, s)	(luaS_newlstr(L, "" s, \
                                  (sizeof(s)/sizeof(char))-1))
 
 #define luaS_fix(s)	l_setbit((s)->tsv.marked, FIXEDBIT)
 
+
+/*
+** as all string are internalized, string equality becomes
+** pointer equality
+*/
+#define eqstr(a,b)	((a) == (b))
+
 LUAI_FUNC void luaS_resize (lua_State *L, int newsize);
 LUAI_FUNC Udata *luaS_newudata (lua_State *L, size_t s, Table *e);
 LUAI_FUNC TString *luaS_newlstr (lua_State *L, const char *str, size_t l);
+LUAI_FUNC TString *luaS_new (lua_State *L, const char *str);
 
 
 #endif
diff --git a/src/lstrlib.c b/src/lstrlib.c
index 7a03489..5e200f1 100644..100755
--- a/src/lstrlib.c
+++ b/src/lstrlib.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lstrlib.c,v 1.132.1.5 2010/05/14 15:34:19 roberto Exp $
+** $Id: lstrlib.c,v 1.170 2011/06/28 17:13:52 roberto Exp $
 ** Standard library for string operations and pattern-matching
 ** See Copyright Notice in lua.h
 */
@@ -20,6 +20,15 @@
 #include "lualib.h"
 
 
+/*
+** maximum number of captures that a pattern can do during
+** pattern-matching. This limit is arbitrary.
+*/
+#if !defined(LUA_MAXCAPTURES)
+#define LUA_MAXCAPTURES		32
+#endif
+
+
 /* macro to `unsign' a character */
 #define uchar(c)        ((unsigned char)(c))
 
@@ -28,39 +37,41 @@
 static int str_len (lua_State *L) {
   size_t l;
   luaL_checklstring(L, 1, &l);
-  lua_pushinteger(L, l);
+  lua_pushinteger(L, (lua_Integer)l);
   return 1;
 }
 
 
-static ptrdiff_t posrelat (ptrdiff_t pos, size_t len) {
-  /* relative string position: negative means back from end */
-  if (pos < 0) pos += (ptrdiff_t)len + 1;
-  return (pos >= 0) ? pos : 0;
+/* translate a relative string position: negative means back from end */
+static size_t posrelat (ptrdiff_t pos, size_t len) {
+  if (pos >= 0) return (size_t)pos;
+  else if (0u - (size_t)pos > len) return 0;
+  else return len - ((size_t)-pos) + 1;
 }
 
 
 static int str_sub (lua_State *L) {
   size_t l;
   const char *s = luaL_checklstring(L, 1, &l);
-  ptrdiff_t start = posrelat(luaL_checkinteger(L, 2), l);
-  ptrdiff_t end = posrelat(luaL_optinteger(L, 3, -1), l);
+  size_t start = posrelat(luaL_checkinteger(L, 2), l);
+  size_t end = posrelat(luaL_optinteger(L, 3, -1), l);
   if (start < 1) start = 1;
-  if (end > (ptrdiff_t)l) end = (ptrdiff_t)l;
+  if (end > l) end = l;
   if (start <= end)
-    lua_pushlstring(L, s+start-1, end-start+1);
+    lua_pushlstring(L, s + start - 1, end - start + 1);
   else lua_pushliteral(L, "");
   return 1;
 }
 
 
 static int str_reverse (lua_State *L) {
-  size_t l;
+  size_t l, i;
   luaL_Buffer b;
   const char *s = luaL_checklstring(L, 1, &l);
-  luaL_buffinit(L, &b);
-  while (l--) luaL_addchar(&b, s[l]);
-  luaL_pushresult(&b);
+  char *p = luaL_buffinitsize(L, &b, l);
+  for (i = 0; i < l; i++)
+    p[i] = s[l - i - 1];
+  luaL_pushresultsize(&b, l);
   return 1;
 }
 
@@ -70,10 +81,10 @@ static int str_lower (lua_State *L) {
   size_t i;
   luaL_Buffer b;
   const char *s = luaL_checklstring(L, 1, &l);
-  luaL_buffinit(L, &b);
+  char *p = luaL_buffinitsize(L, &b, l);
   for (i=0; i<l; i++)
-    luaL_addchar(&b, tolower(uchar(s[i])));
-  luaL_pushresult(&b);
+    p[i] = tolower(uchar(s[i]));
+  luaL_pushresultsize(&b, l);
   return 1;
 }
 
@@ -83,22 +94,36 @@ static int str_upper (lua_State *L) {
   size_t i;
   luaL_Buffer b;
   const char *s = luaL_checklstring(L, 1, &l);
-  luaL_buffinit(L, &b);
+  char *p = luaL_buffinitsize(L, &b, l);
   for (i=0; i<l; i++)
-    luaL_addchar(&b, toupper(uchar(s[i])));
-  luaL_pushresult(&b);
+    p[i] = toupper(uchar(s[i]));
+  luaL_pushresultsize(&b, l);
   return 1;
 }
 
+
+/* reasonable limit to avoid arithmetic overflow */
+#define MAXSIZE		((~(size_t)0) >> 1)
+
 static int str_rep (lua_State *L) {
-  size_t l;
-  luaL_Buffer b;
+  size_t l, lsep;
   const char *s = luaL_checklstring(L, 1, &l);
   int n = luaL_checkint(L, 2);
-  luaL_buffinit(L, &b);
-  while (n-- > 0)
-    luaL_addlstring(&b, s, l);
-  luaL_pushresult(&b);
+  const char *sep = luaL_optlstring(L, 3, "", &lsep);
+  if (n <= 0) lua_pushliteral(L, "");
+  else if (l + lsep < l || l + lsep >= MAXSIZE / n)  /* may overflow? */
+    return luaL_error(L, "resulting string too large");
+  else {
+    size_t totallen = n * l + (n - 1) * lsep;
+    luaL_Buffer b;
+    char *p = luaL_buffinitsize(L, &b, totallen);
+    while (n-- > 1) {  /* first n-1 copies (followed by separator) */
+      memcpy(p, s, l * sizeof(char)); p += l;
+      memcpy(p, sep, lsep * sizeof(char)); p += lsep;
+    }
+    memcpy(p, s, l * sizeof(char));  /* last copy (not followed by separator) */
+    luaL_pushresultsize(&b, totallen);
+  }
   return 1;
 }
 
@@ -106,15 +131,15 @@ static int str_rep (lua_State *L) {
 static int str_byte (lua_State *L) {
   size_t l;
   const char *s = luaL_checklstring(L, 1, &l);
-  ptrdiff_t posi = posrelat(luaL_optinteger(L, 2, 1), l);
-  ptrdiff_t pose = posrelat(luaL_optinteger(L, 3, posi), l);
+  size_t posi = posrelat(luaL_optinteger(L, 2, 1), l);
+  size_t pose = posrelat(luaL_optinteger(L, 3, posi), l);
   int n, i;
-  if (posi <= 0) posi = 1;
-  if ((size_t)pose > l) pose = l;
+  if (posi < 1) posi = 1;
+  if (pose > l) pose = l;
   if (posi > pose) return 0;  /* empty interval; return no values */
   n = (int)(pose -  posi + 1);
   if (posi + n <= pose)  /* overflow? */
-    luaL_error(L, "string slice too long");
+    return luaL_error(L, "string slice too long");
   luaL_checkstack(L, n, "string slice too long");
   for (i=0; i<n; i++)
     lua_pushinteger(L, uchar(s[posi+i-1]));
@@ -126,13 +151,13 @@ static int str_char (lua_State *L) {
   int n = lua_gettop(L);  /* number of arguments */
   int i;
   luaL_Buffer b;
-  luaL_buffinit(L, &b);
+  char *p = luaL_buffinitsize(L, &b, n);
   for (i=1; i<=n; i++) {
     int c = luaL_checkint(L, i);
     luaL_argcheck(L, uchar(c) == c, i, "invalid value");
-    luaL_addchar(&b, uchar(c));
+    p[i - 1] = uchar(c);
   }
-  luaL_pushresult(&b);
+  luaL_pushresultsize(&b, n);
   return 1;
 }
 
@@ -150,7 +175,7 @@ static int str_dump (lua_State *L) {
   lua_settop(L, 1);
   luaL_buffinit(L,&b);
   if (lua_dump(L, writer, &b) != 0)
-    luaL_error(L, "unable to dump given function");
+    return luaL_error(L, "unable to dump given function");
   luaL_pushresult(&b);
   return 1;
 }
@@ -169,7 +194,8 @@ static int str_dump (lua_State *L) {
 
 typedef struct MatchState {
   const char *src_init;  /* init of source string */
-  const char *src_end;  /* end (`\0') of source string */
+  const char *src_end;  /* end ('\0') of source string */
+  const char *p_end;  /* end ('\0') of pattern */
   lua_State *L;
   int level;  /* total number of captures (finished or unfinished) */
   struct {
@@ -186,7 +212,7 @@ typedef struct MatchState {
 static int check_capture (MatchState *ms, int l) {
   l -= '1';
   if (l < 0 || l >= ms->level || ms->capture[l].len == CAP_UNFINISHED)
-    return luaL_error(ms->L, "invalid capture index");
+    return luaL_error(ms->L, "invalid capture index %%%d", l + 1);
   return l;
 }
 
@@ -202,16 +228,16 @@ static int capture_to_close (MatchState *ms) {
 static const char *classend (MatchState *ms, const char *p) {
   switch (*p++) {
     case L_ESC: {
-      if (*p == '\0')
+      if (p == ms->p_end)
         luaL_error(ms->L, "malformed pattern (ends with " LUA_QL("%%") ")");
       return p+1;
     }
     case '[': {
       if (*p == '^') p++;
       do {  /* look for a `]' */
-        if (*p == '\0')
+        if (p == ms->p_end)
           luaL_error(ms->L, "malformed pattern (missing " LUA_QL("]") ")");
-        if (*(p++) == L_ESC && *p != '\0')
+        if (*(p++) == L_ESC && p < ms->p_end)
           p++;  /* skip escapes (e.g. `%]') */
       } while (*p != ']');
       return p+1;
@@ -229,13 +255,14 @@ static int match_class (int c, int cl) {
     case 'a' : res = isalpha(c); break;
     case 'c' : res = iscntrl(c); break;
     case 'd' : res = isdigit(c); break;
+    case 'g' : res = isgraph(c); break;
     case 'l' : res = islower(c); break;
     case 'p' : res = ispunct(c); break;
     case 's' : res = isspace(c); break;
     case 'u' : res = isupper(c); break;
     case 'w' : res = isalnum(c); break;
     case 'x' : res = isxdigit(c); break;
-    case 'z' : res = (c == 0); break;
+    case 'z' : res = (c == 0); break;  /* deprecated option */
     default: return (cl == c);
   }
   return (islower(cl) ? res : !res);
@@ -280,8 +307,9 @@ static const char *match (MatchState *ms, const char *s, const char *p);
 
 static const char *matchbalance (MatchState *ms, const char *s,
                                    const char *p) {
-  if (*p == 0 || *(p+1) == 0)
-    luaL_error(ms->L, "unbalanced pattern");
+  if (p >= ms->p_end - 1)
+    luaL_error(ms->L, "malformed pattern "
+                      "(missing arguments to " LUA_QL("%%b") ")");
   if (*s != *p) return NULL;
   else {
     int b = *p;
@@ -364,6 +392,8 @@ static const char *match_capture (MatchState *ms, const char *s, int l) {
 
 static const char *match (MatchState *ms, const char *s, const char *p) {
   init: /* using goto's to optimize tail recursion */
+  if (p == ms->p_end)  /* end of pattern? */
+    return s;  /* match succeeded */
   switch (*p) {
     case '(': {  /* start capture */
       if (*(p+1) == ')')  /* position capture? */
@@ -374,7 +404,12 @@ static const char *match (MatchState *ms, const char *s, const char *p) {
     case ')': {  /* end capture */
       return end_capture(ms, s, p+1);
     }
-    case L_ESC: {
+    case '$': {
+      if ((p+1) == ms->p_end)  /* is the `$' the last char in pattern? */
+        return (s == ms->src_end) ? s : NULL;  /* check end of string */
+      else goto dflt;
+    }
+    case L_ESC: {  /* escaped sequences not in the format class[*+?-]? */
       switch (*(p+1)) {
         case 'b': {  /* balanced string? */
           s = matchbalance(ms, s, p+2);
@@ -393,27 +428,19 @@ static const char *match (MatchState *ms, const char *s, const char *p) {
              !matchbracketclass(uchar(*s), p, ep-1)) return NULL;
           p=ep; goto init;  /* else return match(ms, s, ep); */
         }
-        default: {
-          if (isdigit(uchar(*(p+1)))) {  /* capture results (%0-%9)? */
-            s = match_capture(ms, s, uchar(*(p+1)));
-            if (s == NULL) return NULL;
-            p+=2; goto init;  /* else return match(ms, s, p+2) */
-          }
-          goto dflt;  /* case default */
+        case '0': case '1': case '2': case '3':
+        case '4': case '5': case '6': case '7':
+        case '8': case '9': {  /* capture results (%0-%9)? */
+          s = match_capture(ms, s, uchar(*(p+1)));
+          if (s == NULL) return NULL;
+          p+=2; goto init;  /* else return match(ms, s, p+2) */
         }
+        default: goto dflt;
       }
     }
-    case '\0': {  /* end of pattern */
-      return s;  /* match succeeded */
-    }
-    case '$': {
-      if (*(p+1) == '\0')  /* is the `$' the last char in pattern? */
-        return (s == ms->src_end) ? s : NULL;  /* check end of string */
-      else goto dflt;
-    }
-    default: dflt: {  /* it is a pattern item */
+    default: dflt: {  /* pattern class plus optional suffix */
       const char *ep = classend(ms, p);  /* points to what is next */
-      int m = s<ms->src_end && singlematch(uchar(*s), p, ep);
+      int m = s < ms->src_end && singlematch(uchar(*s), p, ep);
       switch (*ep) {
         case '?': {  /* optional */
           const char *res;
@@ -492,37 +519,56 @@ static int push_captures (MatchState *ms, const char *s, const char *e) {
 }
 
 
+/* check whether pattern has no special characters */
+static int nospecials (const char *p, size_t l) {
+  size_t upto = 0;
+  do {
+    if (strpbrk(p + upto, SPECIALS))
+      return 0;  /* pattern has a special character */
+    upto += strlen(p + upto) + 1;  /* may have more after \0 */
+  } while (upto <= l);
+  return 1;  /* no special chars found */
+}
+
+
 static int str_find_aux (lua_State *L, int find) {
-  size_t l1, l2;
-  const char *s = luaL_checklstring(L, 1, &l1);
-  const char *p = luaL_checklstring(L, 2, &l2);
-  ptrdiff_t init = posrelat(luaL_optinteger(L, 3, 1), l1) - 1;
-  if (init < 0) init = 0;
-  else if ((size_t)(init) > l1) init = (ptrdiff_t)l1;
-  if (find && (lua_toboolean(L, 4) ||  /* explicit request? */
-      strpbrk(p, SPECIALS) == NULL)) {  /* or no special characters? */
+  size_t ls, lp;
+  const char *s = luaL_checklstring(L, 1, &ls);
+  const char *p = luaL_checklstring(L, 2, &lp);
+  size_t init = posrelat(luaL_optinteger(L, 3, 1), ls);
+  if (init < 1) init = 1;
+  else if (init > ls + 1) {  /* start after string's end? */
+    lua_pushnil(L);  /* cannot find anything */
+    return 1;
+  }
+  /* explicit request or no special characters? */
+  if (find && (lua_toboolean(L, 4) || nospecials(p, lp))) {
     /* do a plain search */
-    const char *s2 = lmemfind(s+init, l1-init, p, l2);
+    const char *s2 = lmemfind(s + init - 1, ls - init + 1, p, lp);
     if (s2) {
-      lua_pushinteger(L, s2-s+1);
-      lua_pushinteger(L, s2-s+l2);
+      lua_pushinteger(L, s2 - s + 1);
+      lua_pushinteger(L, s2 - s + lp);
       return 2;
     }
   }
   else {
     MatchState ms;
-    int anchor = (*p == '^') ? (p++, 1) : 0;
-    const char *s1=s+init;
+    const char *s1 = s + init - 1;
+    int anchor = (*p == '^');
+    if (anchor) {
+      p++; lp--;  /* skip anchor character */
+    }
     ms.L = L;
     ms.src_init = s;
-    ms.src_end = s+l1;
+    ms.src_end = s + ls;
+    ms.p_end = p + lp;
     do {
       const char *res;
       ms.level = 0;
       if ((res=match(&ms, s1, p)) != NULL) {
         if (find) {
-          lua_pushinteger(L, s1-s+1);  /* start */
-          lua_pushinteger(L, res-s);   /* end */
+          lua_pushinteger(L, s1 - s + 1);  /* start */
+          lua_pushinteger(L, res - s);   /* end */
           return push_captures(&ms, NULL, 0) + 2;
         }
         else
@@ -547,13 +593,14 @@ static int str_match (lua_State *L) {
 
 static int gmatch_aux (lua_State *L) {
   MatchState ms;
-  size_t ls;
+  size_t ls, lp;
   const char *s = lua_tolstring(L, lua_upvalueindex(1), &ls);
-  const char *p = lua_tostring(L, lua_upvalueindex(2));
+  const char *p = lua_tolstring(L, lua_upvalueindex(2), &lp);
   const char *src;
   ms.L = L;
   ms.src_init = s;
   ms.src_end = s+ls;
+  ms.p_end = p + lp;
   for (src = s + (size_t)lua_tointeger(L, lua_upvalueindex(3));
        src <= ms.src_end;
        src++) {
@@ -581,12 +628,6 @@ static int gmatch (lua_State *L) {
 }
 
 
-static int gfind_nodef (lua_State *L) {
-  return luaL_error(L, LUA_QL("string.gfind") " was renamed to "
-                       LUA_QL("string.gmatch"));
-}
-
-
 static void add_s (MatchState *ms, luaL_Buffer *b, const char *s,
                                                    const char *e) {
   size_t l, i;
@@ -596,8 +637,12 @@ static void add_s (MatchState *ms, luaL_Buffer *b, const char *s,
       luaL_addchar(b, news[i]);
     else {
       i++;  /* skip ESC */
-      if (!isdigit(uchar(news[i])))
+      if (!isdigit(uchar(news[i]))) {
+        if (news[i] != L_ESC)
+          luaL_error(ms->L, "invalid use of " LUA_QL("%c")
+                           " in replacement string", L_ESC);
         luaL_addchar(b, news[i]);
+      }
       else if (news[i] == '0')
           luaL_addlstring(b, s, e - s);
       else {
@@ -610,14 +655,9 @@ static void add_s (MatchState *ms, luaL_Buffer *b, const char *s,
 
 
 static void add_value (MatchState *ms, luaL_Buffer *b, const char *s,
-                                                       const char *e) {
+                                       const char *e, int tr) {
   lua_State *L = ms->L;
-  switch (lua_type(L, 3)) {
-    case LUA_TNUMBER:
-    case LUA_TSTRING: {
-      add_s(ms, b, s, e);
-      return;
-    }
+  switch (tr) {
     case LUA_TFUNCTION: {
       int n;
       lua_pushvalue(L, 3);
@@ -630,41 +670,49 @@ static void add_value (MatchState *ms, luaL_Buffer *b, const char *s,
       lua_gettable(L, 3);
       break;
     }
+    default: {  /* LUA_TNUMBER or LUA_TSTRING */
+      add_s(ms, b, s, e);
+      return;
+    }
   }
   if (!lua_toboolean(L, -1)) {  /* nil or false? */
     lua_pop(L, 1);
     lua_pushlstring(L, s, e - s);  /* keep original text */
   }
   else if (!lua_isstring(L, -1))
-    luaL_error(L, "invalid replacement value (a %s)", luaL_typename(L, -1)); 
+    luaL_error(L, "invalid replacement value (a %s)", luaL_typename(L, -1));
   luaL_addvalue(b);  /* add result to accumulator */
 }
 
 
 static int str_gsub (lua_State *L) {
-  size_t srcl;
+  size_t srcl, lp;
   const char *src = luaL_checklstring(L, 1, &srcl);
-  const char *p = luaL_checkstring(L, 2);
-  int  tr = lua_type(L, 3);
-  int max_s = luaL_optint(L, 4, srcl+1);
-  int anchor = (*p == '^') ? (p++, 1) : 0;
-  int n = 0;
+  const char *p = luaL_checklstring(L, 2, &lp);
+  int tr = lua_type(L, 3);
+  size_t max_s = luaL_optinteger(L, 4, srcl+1);
+  int anchor = (*p == '^');
+  size_t n = 0;
   MatchState ms;
   luaL_Buffer b;
   luaL_argcheck(L, tr == LUA_TNUMBER || tr == LUA_TSTRING ||
                    tr == LUA_TFUNCTION || tr == LUA_TTABLE, 3,
                       "string/function/table expected");
   luaL_buffinit(L, &b);
+  if (anchor) {
+    p++; lp--;  /* skip anchor character */
+  }
   ms.L = L;
   ms.src_init = src;
   ms.src_end = src+srcl;
+  ms.p_end = p + lp;
   while (n < max_s) {
     const char *e;
     ms.level = 0;
     e = match(&ms, src, p);
     if (e) {
       n++;
-      add_value(&ms, &b, src, e);
+      add_value(&ms, &b, src, e, tr);
     }
     if (e && e>src) /* non empty match? */
       src = e;  /* skip it */
@@ -682,6 +730,46 @@ static int str_gsub (lua_State *L) {
 /* }====================================================== */
 
 
+
+/*
+** {======================================================
+** STRING FORMAT
+** =======================================================
+*/
+
+/*
+** LUA_INTFRMLEN is the length modifier for integer conversions in
+** 'string.format'; LUA_INTFRM_T is the integer type corresponding to
+** the previous length
+*/
+#if !defined(LUA_INTFRMLEN)	/* { */
+#if defined(LUA_USE_LONGLONG)
+
+#define LUA_INTFRMLEN           "ll"
+#define LUA_INTFRM_T            long long
+
+#else
+
+#define LUA_INTFRMLEN           "l"
+#define LUA_INTFRM_T            long
+
+#endif
+#endif				/* } */
+
+
+/*
+** LUA_FLTFRMLEN is the length modifier for float conversions in
+** 'string.format'; LUA_FLTFRM_T is the float type corresponding to
+** the previous length
+*/
+#if !defined(LUA_FLTFRMLEN)
+
+#define LUA_FLTFRMLEN           ""
+#define LUA_FLTFRM_T            double
+
+#endif
+
+
 /* maximum size of each formatted item (> len(format('%99.99f', -1e308))) */
 #define MAX_ITEM	512
 /* valid flags in a format specification */
@@ -698,25 +786,20 @@ static void addquoted (lua_State *L, luaL_Buffer *b, int arg) {
   const char *s = luaL_checklstring(L, arg, &l);
   luaL_addchar(b, '"');
   while (l--) {
-    switch (*s) {
-      case '"': case '\\': case '\n': {
-        luaL_addchar(b, '\\');
-        luaL_addchar(b, *s);
-        break;
-      }
-      case '\r': {
-        luaL_addlstring(b, "\\r", 2);
-        break;
-      }
-      case '\0': {
-        luaL_addlstring(b, "\\000", 4);
-        break;
-      }
-      default: {
-        luaL_addchar(b, *s);
-        break;
-      }
+    if (*s == '"' || *s == '\\' || *s == '\n') {
+      luaL_addchar(b, '\\');
+      luaL_addchar(b, *s);
+    }
+    else if (*s == '\0' || iscntrl(uchar(*s))) {
+      char buff[10];
+      if (!isdigit(uchar(*(s+1))))
+        sprintf(buff, "\\%d", (int)uchar(*s));
+      else
+        sprintf(buff, "\\%03d", (int)uchar(*s));
+      luaL_addstring(b, buff);
     }
+    else
+      luaL_addchar(b, *s);
     s++;
   }
   luaL_addchar(b, '"');
@@ -725,7 +808,7 @@ static void addquoted (lua_State *L, luaL_Buffer *b, int arg) {
 static const char *scanformat (lua_State *L, const char *strfrmt, char *form) {
   const char *p = strfrmt;
   while (*p != '\0' && strchr(FLAGS, *p) != NULL) p++;  /* skip flags */
-  if ((size_t)(p - strfrmt) >= sizeof(FLAGS))
+  if ((size_t)(p - strfrmt) >= sizeof(FLAGS)/sizeof(char))
     luaL_error(L, "invalid format (repeated flags)");
   if (isdigit(uchar(*p))) p++;  /* skip width */
   if (isdigit(uchar(*p))) p++;  /* (2 digits at most) */
@@ -737,19 +820,23 @@ static const char *scanformat (lua_State *L, const char *strfrmt, char *form) {
   if (isdigit(uchar(*p)))
     luaL_error(L, "invalid format (width or precision too long)");
   *(form++) = '%';
-  strncpy(form, strfrmt, p - strfrmt + 1);
+  memcpy(form, strfrmt, (p - strfrmt + 1) * sizeof(char));
   form += p - strfrmt + 1;
   *form = '\0';
   return p;
 }
 
 
-static void addintlen (char *form) {
+/*
+** add length modifier into formats
+*/
+static void addlenmod (char *form, const char *lenmod) {
   size_t l = strlen(form);
+  size_t lm = strlen(lenmod);
   char spec = form[l - 1];
-  strcpy(form + l - 1, LUA_INTFRMLEN);
-  form[l + sizeof(LUA_INTFRMLEN) - 2] = spec;
-  form[l + sizeof(LUA_INTFRMLEN) - 1] = '\0';
+  strcpy(form + l - 1, lenmod);
+  form[l + lm - 1] = spec;
+  form[l + lm] = '\0';
 }
 
 
@@ -768,46 +855,50 @@ static int str_format (lua_State *L) {
       luaL_addchar(&b, *strfrmt++);  /* %% */
     else { /* format item */
       char form[MAX_FORMAT];  /* to store the format (`%...') */
-      char buff[MAX_ITEM];  /* to store the formatted item */
+      char *buff = luaL_prepbuffsize(&b, MAX_ITEM);  /* to put formatted item */
+      int nb = 0;  /* number of bytes in added item */
       if (++arg > top)
         luaL_argerror(L, arg, "no value");
       strfrmt = scanformat(L, strfrmt, form);
       switch (*strfrmt++) {
         case 'c': {
-          sprintf(buff, form, (int)luaL_checknumber(L, arg));
-          break;
-        }
-        case 'd':  case 'i': {
-          addintlen(form);
-          sprintf(buff, form, (LUA_INTFRM_T)luaL_checknumber(L, arg));
+          nb = sprintf(buff, form, luaL_checkint(L, arg));
           break;
         }
+        case 'd':  case 'i':
         case 'o':  case 'u':  case 'x':  case 'X': {
-          addintlen(form);
-          sprintf(buff, form, (unsigned LUA_INTFRM_T)luaL_checknumber(L, arg));
+          lua_Number n = luaL_checknumber(L, arg);
+          LUA_INTFRM_T r = (n < 0) ? (LUA_INTFRM_T)n :
+                                     (LUA_INTFRM_T)(unsigned LUA_INTFRM_T)n;
+          addlenmod(form, LUA_INTFRMLEN);
+          nb = sprintf(buff, form, r);
           break;
         }
         case 'e':  case 'E': case 'f':
+#if defined(LUA_USE_AFORMAT)
+        case 'a': case 'A':
+#endif
         case 'g': case 'G': {
-          sprintf(buff, form, (double)luaL_checknumber(L, arg));
+          addlenmod(form, LUA_FLTFRMLEN);
+          nb = sprintf(buff, form, (LUA_FLTFRM_T)luaL_checknumber(L, arg));
           break;
         }
         case 'q': {
           addquoted(L, &b, arg);
-          continue;  /* skip the 'addsize' at the end */
+          break;
         }
         case 's': {
           size_t l;
-          const char *s = luaL_checklstring(L, arg, &l);
+          const char *s = luaL_tolstring(L, arg, &l);
           if (!strchr(form, '.') && l >= 100) {
             /* no precision and string is too long to be formatted;
                keep original string */
-            lua_pushvalue(L, arg);
             luaL_addvalue(&b);
-            continue;  /* skip the `addsize' at the end */
+            break;
           }
           else {
-            sprintf(buff, form, s);
+            nb = sprintf(buff, form, s);
+            lua_pop(L, 1);  /* remove result from 'luaL_tolstring' */
             break;
           }
         }
@@ -816,13 +907,15 @@ static int str_format (lua_State *L) {
                                LUA_QL("format"), *(strfrmt - 1));
         }
       }
-      luaL_addlstring(&b, buff, strlen(buff));
+      luaL_addsize(&b, nb);
     }
   }
   luaL_pushresult(&b);
   return 1;
 }
 
+/* }====================================================== */
+
 
 static const luaL_Reg strlib[] = {
   {"byte", str_byte},
@@ -830,7 +923,6 @@ static const luaL_Reg strlib[] = {
   {"dump", str_dump},
   {"find", str_find},
   {"format", str_format},
-  {"gfind", gfind_nodef},
   {"gmatch", gmatch},
   {"gsub", str_gsub},
   {"len", str_len},
@@ -845,13 +937,13 @@ static const luaL_Reg strlib[] = {
 
 
 static void createmetatable (lua_State *L) {
-  lua_createtable(L, 0, 1);  /* create metatable for strings */
+  lua_createtable(L, 0, 1);  /* table to be metatable for strings */
   lua_pushliteral(L, "");  /* dummy string */
-  lua_pushvalue(L, -2);
-  lua_setmetatable(L, -2);  /* set string metatable */
+  lua_pushvalue(L, -2);  /* copy table */
+  lua_setmetatable(L, -2);  /* set table as metatable for strings */
   lua_pop(L, 1);  /* pop dummy string */
-  lua_pushvalue(L, -2);  /* string library... */
-  lua_setfield(L, -2, "__index");  /* ...is the __index metamethod */
+  lua_pushvalue(L, -2);  /* get string library */
+  lua_setfield(L, -2, "__index");  /* metatable.__index = string */
   lua_pop(L, 1);  /* pop metatable */
 }
 
@@ -859,12 +951,8 @@ static void createmetatable (lua_State *L) {
 /*
 ** Open string library
 */
-LUALIB_API int luaopen_string (lua_State *L) {
-  luaL_register(L, LUA_STRLIBNAME, strlib);
-#if defined(LUA_COMPAT_GFIND)
-  lua_getfield(L, -1, "gmatch");
-  lua_setfield(L, -2, "gfind");
-#endif
+LUAMOD_API int luaopen_string (lua_State *L) {
+  luaL_newlib(L, strlib);
   createmetatable(L);
   return 1;
 }
diff --git a/src/ltable.c b/src/ltable.c
index ec84f4f..a937959 100644..100755
--- a/src/ltable.c
+++ b/src/ltable.c
@@ -1,5 +1,5 @@
 /*
-** $Id: ltable.c,v 2.32.1.2 2007/12/28 15:32:23 roberto Exp $
+** $Id: ltable.c,v 2.60 2011/06/16 14:14:31 roberto Exp $
 ** Lua tables (hash)
 ** See Copyright Notice in lua.h
 */
@@ -18,7 +18,6 @@
 ** Hence even when the load factor reaches 100%, performance remains good.
 */
 
-#include <math.h>
 #include <string.h>
 
 #define ltable_c
@@ -32,14 +31,16 @@
 #include "lmem.h"
 #include "lobject.h"
 #include "lstate.h"
+#include "lstring.h"
 #include "ltable.h"
+#include "lvm.h"
 
 
 /*
 ** max size of array part is 2^MAXBITS
 */
-#if LUAI_BITSINT > 26
-#define MAXBITS		26
+#if LUAI_BITSINT >= 32
+#define MAXBITS		30
 #else
 #define MAXBITS		(LUAI_BITSINT-2)
 #endif
@@ -48,7 +49,7 @@
 
 
 #define hashpow2(t,n)      (gnode(t, lmod((n), sizenode(t))))
-  
+
 #define hashstr(t,str)  hashpow2(t, (str)->tsv.hash)
 #define hashboolean(t,p)        hashpow2(t, p)
 
@@ -72,9 +73,11 @@
 
 #define dummynode		(&dummynode_)
 
+#define isdummy(n)		((n) == dummynode)
+
 static const Node dummynode_ = {
-  {{NULL}, LUA_TNIL},  /* value */
-  {{{NULL}, LUA_TNIL, NULL}}  /* key */
+  {NILCONSTANT},  /* value */
+  {{NILCONSTANT, NULL}}  /* key */
 };
 
 
@@ -82,13 +85,14 @@ static const Node dummynode_ = {
 ** hash for lua_Numbers
 */
 static Node *hashnum (const Table *t, lua_Number n) {
-  unsigned int a[numints];
   int i;
-  if (luai_numeq(n, 0))  /* avoid problems with -0 */
-    return gnode(t, 0);
-  memcpy(a, &n, sizeof(a));
-  for (i = 1; i < numints; i++) a[0] += a[i];
-  return hashmod(t, a[0]);
+  luai_hashnum(i, n);
+  if (i < 0) {
+    if (cast(unsigned int, i) == 0u - i)  /* use unsigned to avoid overflows */
+      i = 0;  /* handle INT_MIN */
+    i = -i;  /* must be a positive value */
+  }
+  return hashmod(t, i);
 }
 
 
@@ -107,6 +111,8 @@ static Node *mainposition (const Table *t, const TValue *key) {
       return hashboolean(t, bvalue(key));
     case LUA_TLIGHTUSERDATA:
       return hashpointer(t, pvalue(key));
+    case LUA_TLCF:
+      return hashpointer(t, fvalue(key));
     default:
       return hashpointer(t, gcvalue(key));
   }
@@ -132,7 +138,7 @@ static int arrayindex (const TValue *key) {
 /*
 ** returns the index of a `key' for table traversals. First goes all
 ** elements in the array part, then elements in the hash part. The
-** beginning of a traversal is signalled by -1.
+** beginning of a traversal is signaled by -1.
 */
 static int findindex (lua_State *L, Table *t, StkId key) {
   int i;
@@ -144,8 +150,8 @@ static int findindex (lua_State *L, Table *t, StkId key) {
     Node *n = mainposition(t, key);
     do {  /* check whether `key' is somewhere in the chain */
       /* key may be dead already, but it is ok to use it in `next' */
-      if (luaO_rawequalObj(key2tval(n), key) ||
-            (ttype(gkey(n)) == LUA_TDEADKEY && iscollectable(key) &&
+      if (luaV_rawequalobj(gkey(n), key) ||
+            (ttisdeadkey(gkey(n)) && iscollectable(key) &&
              gcvalue(gkey(n)) == gcvalue(key))) {
         i = cast_int(n - gnode(t, 0));  /* key index in hash table */
         /* hash elements are numbered after array ones */
@@ -170,7 +176,7 @@ int luaH_next (lua_State *L, Table *t, StkId key) {
   }
   for (i -= t->sizearray; i < sizenode(t); i++) {  /* then hash part */
     if (!ttisnil(gval(gnode(t, i)))) {  /* a non-nil value? */
-      setobj2s(L, key, key2tval(gnode(t, i)));
+      setobj2s(L, key, gkey(gnode(t, i)));
       setobj2s(L, key+1, gval(gnode(t, i)));
       return 1;
     }
@@ -211,7 +217,7 @@ static int computesizes (int nums[], int *narray) {
 static int countint (const TValue *key, int *nums) {
   int k = arrayindex(key);
   if (0 < k && k <= MAXASIZE) {  /* is `key' an appropriate array index? */
-    nums[ceillog2(k)]++;  /* count as such */
+    nums[luaO_ceillog2(k)]++;  /* count as such */
     return 1;
   }
   else
@@ -251,7 +257,7 @@ static int numusehash (const Table *t, int *nums, int *pnasize) {
   while (i--) {
     Node *n = &t->node[i];
     if (!ttisnil(gval(n))) {
-      ause += countint(key2tval(n), nums);
+      ause += countint(gkey(n), nums);
       totaluse++;
     }
   }
@@ -277,7 +283,7 @@ static void setnodevector (lua_State *L, Table *t, int size) {
   }
   else {
     int i;
-    lsize = ceillog2(size);
+    lsize = luaO_ceillog2(size);
     if (lsize > MAXBITS)
       luaG_runerror(L, "table overflow");
     size = twoto(lsize);
@@ -294,7 +300,7 @@ static void setnodevector (lua_State *L, Table *t, int size) {
 }
 
 
-static void resize (lua_State *L, Table *t, int nasize, int nhsize) {
+void luaH_resize (lua_State *L, Table *t, int nasize, int nhsize) {
   int i;
   int oldasize = t->sizearray;
   int oldhsize = t->lsizenode;
@@ -302,13 +308,13 @@ static void resize (lua_State *L, Table *t, int nasize, int nhsize) {
   if (nasize > oldasize)  /* array part must grow? */
     setarrayvector(L, t, nasize);
   /* create new hash part with appropriate size */
-  setnodevector(L, t, nhsize);  
+  setnodevector(L, t, nhsize);
   if (nasize < oldasize) {  /* array part must shrink? */
     t->sizearray = nasize;
     /* re-insert elements from vanishing slice */
     for (i=nasize; i<oldasize; i++) {
       if (!ttisnil(&t->array[i]))
-        setobjt2t(L, luaH_setnum(L, t, i+1), &t->array[i]);
+        setobjt2t(L, luaH_setint(L, t, i+1), &t->array[i]);
     }
     /* shrink array */
     luaM_reallocvector(L, t->array, oldasize, nasize, TValue);
@@ -317,22 +323,22 @@ static void resize (lua_State *L, Table *t, int nasize, int nhsize) {
   for (i = twoto(oldhsize) - 1; i >= 0; i--) {
     Node *old = nold+i;
     if (!ttisnil(gval(old)))
-      setobjt2t(L, luaH_set(L, t, key2tval(old)), gval(old));
+      setobjt2t(L, luaH_set(L, t, gkey(old)), gval(old));
   }
-  if (nold != dummynode)
-    luaM_freearray(L, nold, twoto(oldhsize), Node);  /* free old array */
+  if (!isdummy(nold))
+    luaM_freearray(L, nold, twoto(oldhsize));  /* free old array */
 }
 
 
 void luaH_resizearray (lua_State *L, Table *t, int nasize) {
-  int nsize = (t->node == dummynode) ? 0 : sizenode(t);
-  resize(L, t, nasize, nsize);
+  int nsize = isdummy(t->node) ? 0 : sizenode(t);
+  luaH_resize(L, t, nasize, nsize);
 }
 
 
 static void rehash (lua_State *L, Table *t, const TValue *ek) {
   int nasize, na;
-  int nums[MAXBITS+1];  /* nums[i] = number of keys between 2^(i-1) and 2^i */
+  int nums[MAXBITS+1];  /* nums[i] = number of keys with 2^(i-1) < k <= 2^i */
   int i;
   int totaluse;
   for (i=0; i<=MAXBITS; i++) nums[i] = 0;  /* reset counts */
@@ -345,7 +351,7 @@ static void rehash (lua_State *L, Table *t, const TValue *ek) {
   /* compute new size for array part */
   na = computesizes(nums, &nasize);
   /* resize the table to new computed sizes */
-  resize(L, t, nasize, totaluse - na);
+  luaH_resize(L, t, nasize, totaluse - na);
 }
 
 
@@ -355,32 +361,28 @@ static void rehash (lua_State *L, Table *t, const TValue *ek) {
 */
 
 
-Table *luaH_new (lua_State *L, int narray, int nhash) {
-  Table *t = luaM_new(L, Table);
-  luaC_link(L, obj2gco(t), LUA_TTABLE);
+Table *luaH_new (lua_State *L) {
+  Table *t = &luaC_newobj(L, LUA_TTABLE, sizeof(Table), NULL, 0)->h;
   t->metatable = NULL;
   t->flags = cast_byte(~0);
-  /* temporary values (kept only if some malloc fails) */
   t->array = NULL;
   t->sizearray = 0;
-  t->lsizenode = 0;
-  t->node = cast(Node *, dummynode);
-  setarrayvector(L, t, narray);
-  setnodevector(L, t, nhash);
+  setnodevector(L, t, 0);
   return t;
 }
 
 
 void luaH_free (lua_State *L, Table *t) {
-  if (t->node != dummynode)
-    luaM_freearray(L, t->node, sizenode(t), Node);
-  luaM_freearray(L, t->array, t->sizearray, TValue);
+  if (!isdummy(t->node))
+    luaM_freearray(L, t->node, sizenode(t));
+  luaM_freearray(L, t->array, t->sizearray);
   luaM_free(L, t);
 }
 
 
 static Node *getfreepos (Table *t) {
-  while (t->lastfree-- > t->node) {
+  while (t->lastfree > t->node) {
+    t->lastfree--;
     if (ttisnil(gkey(t->lastfree)))
       return t->lastfree;
   }
@@ -390,23 +392,23 @@ static Node *getfreepos (Table *t) {
 
 
 /*
-** inserts a new key into a hash table; first, check whether key's main 
-** position is free. If not, check whether colliding node is in its main 
-** position or not: if it is not, move colliding node to an empty place and 
-** put new key in its main position; otherwise (colliding node is in its main 
-** position), new key goes to an empty position. 
+** inserts a new key into a hash table; first, check whether key's main
+** position is free. If not, check whether colliding node is in its main
+** position or not: if it is not, move colliding node to an empty place and
+** put new key in its main position; otherwise (colliding node is in its main
+** position), new key goes to an empty position.
 */
 static TValue *newkey (lua_State *L, Table *t, const TValue *key) {
   Node *mp = mainposition(t, key);
-  if (!ttisnil(gval(mp)) || mp == dummynode) {
+  if (!ttisnil(gval(mp)) || isdummy(mp)) {  /* main position is taken? */
     Node *othern;
     Node *n = getfreepos(t);  /* get a free place */
     if (n == NULL) {  /* cannot find a free place? */
       rehash(L, t, key);  /* grow table */
       return luaH_set(L, t, key);  /* re-insert key into grown table */
     }
-    lua_assert(n != dummynode);
-    othern = mainposition(t, key2tval(mp));
+    lua_assert(!isdummy(n));
+    othern = mainposition(t, gkey(mp));
     if (othern != mp) {  /* is colliding node out of its main position? */
       /* yes; move colliding node into free position */
       while (gnext(othern) != mp) othern = gnext(othern);  /* find previous */
@@ -422,8 +424,8 @@ static TValue *newkey (lua_State *L, Table *t, const TValue *key) {
       mp = n;
     }
   }
-  gkey(mp)->value = key->value; gkey(mp)->tt = key->tt;
-  luaC_barriert(L, t, key);
+  setobj2t(L, gkey(mp), key);
+  luaC_barrierback(L, obj2gco(t), key);
   lua_assert(ttisnil(gval(mp)));
   return gval(mp);
 }
@@ -432,7 +434,7 @@ static TValue *newkey (lua_State *L, Table *t, const TValue *key) {
 /*
 ** search function for integers
 */
-const TValue *luaH_getnum (Table *t, int key) {
+const TValue *luaH_getint (Table *t, int key) {
   /* (1 <= key && key <= t->sizearray) */
   if (cast(unsigned int, key-1) < cast(unsigned int, t->sizearray))
     return &t->array[key-1];
@@ -455,7 +457,7 @@ const TValue *luaH_getnum (Table *t, int key) {
 const TValue *luaH_getstr (Table *t, TString *key) {
   Node *n = hashstr(t, key);
   do {  /* check whether `key' is somewhere in the chain */
-    if (ttisstring(gkey(n)) && rawtsvalue(gkey(n)) == key)
+    if (ttisstring(gkey(n)) && eqstr(rawtsvalue(gkey(n)), key))
       return gval(n);  /* that's it */
     else n = gnext(n);
   } while (n);
@@ -467,7 +469,7 @@ const TValue *luaH_getstr (Table *t, TString *key) {
 ** main search function
 */
 const TValue *luaH_get (Table *t, const TValue *key) {
-  switch (ttype(key)) {
+  switch (ttypenv(key)) {
     case LUA_TNIL: return luaO_nilobject;
     case LUA_TSTRING: return luaH_getstr(t, rawtsvalue(key));
     case LUA_TNUMBER: {
@@ -475,13 +477,13 @@ const TValue *luaH_get (Table *t, const TValue *key) {
       lua_Number n = nvalue(key);
       lua_number2int(k, n);
       if (luai_numeq(cast_num(k), nvalue(key))) /* index is int? */
-        return luaH_getnum(t, k);  /* use specialized version */
+        return luaH_getint(t, k);  /* use specialized version */
       /* else go through */
     }
     default: {
       Node *n = mainposition(t, key);
       do {  /* check whether `key' is somewhere in the chain */
-        if (luaO_rawequalObj(key2tval(n), key))
+        if (luaV_rawequalobj(gkey(n), key))
           return gval(n);  /* that's it */
         else n = gnext(n);
       } while (n);
@@ -498,15 +500,15 @@ TValue *luaH_set (lua_State *L, Table *t, const TValue *key) {
     return cast(TValue *, p);
   else {
     if (ttisnil(key)) luaG_runerror(L, "table index is nil");
-    else if (ttisnumber(key) && luai_numisnan(nvalue(key)))
+    else if (ttisnumber(key) && luai_numisnan(L, nvalue(key)))
       luaG_runerror(L, "table index is NaN");
     return newkey(L, t, key);
   }
 }
 
 
-TValue *luaH_setnum (lua_State *L, Table *t, int key) {
-  const TValue *p = luaH_getnum(t, key);
+TValue *luaH_setint (lua_State *L, Table *t, int key) {
+  const TValue *p = luaH_getint(t, key);
   if (p != luaO_nilobject)
     return cast(TValue *, p);
   else {
@@ -533,20 +535,20 @@ static int unbound_search (Table *t, unsigned int j) {
   unsigned int i = j;  /* i is zero or a present index */
   j++;
   /* find `i' and `j' such that i is present and j is not */
-  while (!ttisnil(luaH_getnum(t, j))) {
+  while (!ttisnil(luaH_getint(t, j))) {
     i = j;
     j *= 2;
     if (j > cast(unsigned int, MAX_INT)) {  /* overflow? */
       /* table was built with bad purposes: resort to linear search */
       i = 1;
-      while (!ttisnil(luaH_getnum(t, i))) i++;
+      while (!ttisnil(luaH_getint(t, i))) i++;
       return i - 1;
     }
   }
   /* now do a binary search between them */
   while (j - i > 1) {
     unsigned int m = (i+j)/2;
-    if (ttisnil(luaH_getnum(t, m))) j = m;
+    if (ttisnil(luaH_getint(t, m))) j = m;
     else i = m;
   }
   return i;
@@ -570,7 +572,7 @@ int luaH_getn (Table *t) {
     return i;
   }
   /* else must find a boundary in hash part */
-  else if (t->node == dummynode)  /* hash part is empty? */
+  else if (isdummy(t->node))  /* hash part is empty? */
     return j;  /* that is easy... */
   else return unbound_search(t, j);
 }
@@ -583,6 +585,6 @@ Node *luaH_mainposition (const Table *t, const TValue *key) {
   return mainposition(t, key);
 }
 
-int luaH_isdummy (Node *n) { return n == dummynode; }
+int luaH_isdummy (Node *n) { return isdummy(n); }
 
 #endif
diff --git a/src/ltable.h b/src/ltable.h
index f5b9d5e..c14b028 100644..100755
--- a/src/ltable.h
+++ b/src/ltable.h
@@ -1,5 +1,5 @@
 /*
-** $Id: ltable.h,v 2.10.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: ltable.h,v 2.14 2010/06/25 12:18:10 roberto Exp $
 ** Lua tables (hash)
 ** See Copyright Notice in lua.h
 */
@@ -11,20 +11,19 @@
 
 
 #define gnode(t,i)	(&(t)->node[i])
-#define gkey(n)		(&(n)->i_key.nk)
+#define gkey(n)		(&(n)->i_key.tvk)
 #define gval(n)		(&(n)->i_val)
 #define gnext(n)	((n)->i_key.nk.next)
 
-#define key2tval(n)	(&(n)->i_key.tvk)
 
-
-LUAI_FUNC const TValue *luaH_getnum (Table *t, int key);
-LUAI_FUNC TValue *luaH_setnum (lua_State *L, Table *t, int key);
+LUAI_FUNC const TValue *luaH_getint (Table *t, int key);
+LUAI_FUNC TValue *luaH_setint (lua_State *L, Table *t, int key);
 LUAI_FUNC const TValue *luaH_getstr (Table *t, TString *key);
 LUAI_FUNC TValue *luaH_setstr (lua_State *L, Table *t, TString *key);
 LUAI_FUNC const TValue *luaH_get (Table *t, const TValue *key);
 LUAI_FUNC TValue *luaH_set (lua_State *L, Table *t, const TValue *key);
-LUAI_FUNC Table *luaH_new (lua_State *L, int narray, int lnhash);
+LUAI_FUNC Table *luaH_new (lua_State *L);
+LUAI_FUNC void luaH_resize (lua_State *L, Table *t, int nasize, int nhsize);
 LUAI_FUNC void luaH_resizearray (lua_State *L, Table *t, int nasize);
 LUAI_FUNC void luaH_free (lua_State *L, Table *t);
 LUAI_FUNC int luaH_next (lua_State *L, Table *t, StkId key);
diff --git a/src/ltablib.c b/src/ltablib.c
index b6d9cb4..06353c7 100644..100755
--- a/src/ltablib.c
+++ b/src/ltablib.c
@@ -1,5 +1,5 @@
 /*
-** $Id: ltablib.c,v 1.38.1.3 2008/02/14 16:46:58 roberto Exp $
+** $Id: ltablib.c,v 1.61 2011/07/05 12:49:35 roberto Exp $
 ** Library for Table Manipulation
 ** See Copyright Notice in lua.h
 */
@@ -16,43 +16,11 @@
 #include "lualib.h"
 
 
-#define aux_getn(L,n)	(luaL_checktype(L, n, LUA_TTABLE), luaL_getn(L, n))
-
-
-static int foreachi (lua_State *L) {
-  int i;
-  int n = aux_getn(L, 1);
-  luaL_checktype(L, 2, LUA_TFUNCTION);
-  for (i=1; i <= n; i++) {
-    lua_pushvalue(L, 2);  /* function */
-    lua_pushinteger(L, i);  /* 1st argument */
-    lua_rawgeti(L, 1, i);  /* 2nd argument */
-    lua_call(L, 2, 1);
-    if (!lua_isnil(L, -1))
-      return 1;
-    lua_pop(L, 1);  /* remove nil result */
-  }
-  return 0;
-}
-
-
-static int foreach (lua_State *L) {
-  luaL_checktype(L, 1, LUA_TTABLE);
-  luaL_checktype(L, 2, LUA_TFUNCTION);
-  lua_pushnil(L);  /* first key */
-  while (lua_next(L, 1)) {
-    lua_pushvalue(L, 2);  /* function */
-    lua_pushvalue(L, -3);  /* key */
-    lua_pushvalue(L, -3);  /* value */
-    lua_call(L, 2, 1);
-    if (!lua_isnil(L, -1))
-      return 1;
-    lua_pop(L, 2);  /* remove value and result */
-  }
-  return 0;
-}
+#define aux_getn(L,n)  \
+	(luaL_checktype(L, n, LUA_TTABLE), luaL_len(L, n))
 
 
+#if defined(LUA_COMPAT_MAXN)
 static int maxn (lua_State *L) {
   lua_Number max = 0;
   luaL_checktype(L, 1, LUA_TTABLE);
@@ -67,24 +35,7 @@ static int maxn (lua_State *L) {
   lua_pushnumber(L, max);
   return 1;
 }
-
-
-static int getn (lua_State *L) {
-  lua_pushinteger(L, aux_getn(L, 1));
-  return 1;
-}
-
-
-static int setn (lua_State *L) {
-  luaL_checktype(L, 1, LUA_TTABLE);
-#ifndef luaL_setn
-  luaL_setn(L, 1, luaL_checkint(L, 2));
-#else
-  luaL_error(L, LUA_QL("setn") " is obsolete");
 #endif
-  lua_pushvalue(L, 1);
-  return 1;
-}
 
 
 static int tinsert (lua_State *L) {
@@ -109,7 +60,6 @@ static int tinsert (lua_State *L) {
       return luaL_error(L, "wrong number of arguments to " LUA_QL("insert"));
     }
   }
-  luaL_setn(L, 1, e);  /* new size */
   lua_rawseti(L, 1, pos);  /* t[pos] = v */
   return 0;
 }
@@ -119,8 +69,7 @@ static int tremove (lua_State *L) {
   int e = aux_getn(L, 1);
   int pos = luaL_optint(L, 2, e);
   if (!(1 <= pos && pos <= e))  /* position is outside bounds? */
-   return 0;  /* nothing to remove */
-  luaL_setn(L, 1, e - 1);  /* t.n = n-1 */
+    return 0;  /* nothing to remove */
   lua_rawgeti(L, 1, pos);  /* result = t[pos] */
   for ( ;pos<e; pos++) {
     lua_rawgeti(L, 1, pos+1);
@@ -148,7 +97,7 @@ static int tconcat (lua_State *L) {
   const char *sep = luaL_optlstring(L, 2, "", &lsep);
   luaL_checktype(L, 1, LUA_TTABLE);
   i = luaL_optint(L, 3, 1);
-  last = luaL_opt(L, luaL_checkint, 4, luaL_getn(L, 1));
+  last = luaL_opt(L, luaL_checkint, 4, luaL_len(L, 1));
   luaL_buffinit(L, &b);
   for (; i < last; i++) {
     addfield(L, &b, i);
@@ -161,12 +110,55 @@ static int tconcat (lua_State *L) {
 }
 
 
+/*
+** {======================================================
+** Pack/unpack
+** =======================================================
+*/
+
+static int pack (lua_State *L) {
+  int n = lua_gettop(L);  /* number of elements to pack */
+  lua_createtable(L, n, 1);  /* create result table */
+  lua_pushinteger(L, n);
+  lua_setfield(L, -2, "n");  /* t.n = number of elements */
+  if (n > 0) {  /* at least one element? */
+    int i;
+    lua_pushvalue(L, 1);
+    lua_rawseti(L, -2, 1);  /* insert first element */
+    lua_replace(L, 1);  /* move table into index 1 */
+    for (i = n; i >= 2; i--)  /* assign other elements */
+      lua_rawseti(L, 1, i);
+  }
+  lua_pushinteger(L, n);
+  return 2;  /* return table and number of elements */
+}
+
+
+static int 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_len(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;
+}
+
+/* }====================================================== */
+
+
 
 /*
 ** {======================================================
 ** Quicksort
 ** (based on `Algorithms in MODULA-3', Robert Sedgewick;
 **  Addison-Wesley, 1993.)
+** =======================================================
 */
 
 
@@ -187,7 +179,7 @@ static int sort_comp (lua_State *L, int a, int b) {
     return res;
   }
   else  /* a < b? */
-    return lua_lessthan(L, a, b);
+    return lua_compare(L, a, b, LUA_OPLT);
 }
 
 static void auxsort (lua_State *L, int l, int u) {
@@ -224,12 +216,12 @@ static void auxsort (lua_State *L, int l, int u) {
     for (;;) {  /* invariant: a[l..i] <= P <= a[j..u] */
       /* repeat ++i until a[i] >= P */
       while (lua_rawgeti(L, 1, ++i), sort_comp(L, -1, -2)) {
-        if (i>u) luaL_error(L, "invalid order function for sorting");
+        if (i>=u) luaL_error(L, "invalid order function for sorting");
         lua_pop(L, 1);  /* remove a[i] */
       }
       /* repeat --j until a[j] <= P */
       while (lua_rawgeti(L, 1, --j), sort_comp(L, -3, -1)) {
-        if (j<l) luaL_error(L, "invalid order function for sorting");
+        if (j<=l) luaL_error(L, "invalid order function for sorting");
         lua_pop(L, 1);  /* remove a[j] */
       }
       if (j<i) {
@@ -268,20 +260,25 @@ static int sort (lua_State *L) {
 
 static const luaL_Reg tab_funcs[] = {
   {"concat", tconcat},
-  {"foreach", foreach},
-  {"foreachi", foreachi},
-  {"getn", getn},
+#if defined(LUA_COMPAT_MAXN)
   {"maxn", maxn},
+#endif
   {"insert", tinsert},
+  {"pack", pack},
+  {"unpack", unpack},
   {"remove", tremove},
-  {"setn", setn},
   {"sort", sort},
   {NULL, NULL}
 };
 
 
-LUALIB_API int luaopen_table (lua_State *L) {
-  luaL_register(L, LUA_TABLIBNAME, tab_funcs);
+LUAMOD_API int luaopen_table (lua_State *L) {
+  luaL_newlib(L, tab_funcs);
+#if defined(LUA_COMPAT_UNPACK)
+  /* _G.unpack = table.unpack */
+  lua_getfield(L, -1, "unpack");
+  lua_setglobal(L, "unpack");
+#endif
   return 1;
 }
 
diff --git a/src/ltm.c b/src/ltm.c
index c27f0f6..e70006d 100644..100755
--- a/src/ltm.c
+++ b/src/ltm.c
@@ -1,5 +1,5 @@
 /*
-** $Id: ltm.c,v 2.8.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: ltm.c,v 2.14 2011/06/02 19:31:40 roberto Exp $
 ** Tag methods
 ** See Copyright Notice in lua.h
 */
@@ -19,20 +19,22 @@
 #include "ltm.h"
 
 
+static const char udatatypename[] = "userdata";
 
-const char *const luaT_typenames[] = {
-  "nil", "boolean", "userdata", "number",
-  "string", "table", "function", "userdata", "thread",
-  "proto", "upval"
+LUAI_DDEF const char *const luaT_typenames_[LUA_TOTALTAGS] = {
+  "no value",
+  "nil", "boolean", udatatypename, "number",
+  "string", "table", "function", udatatypename, "thread",
+  "proto", "upval"  /* these last two cases are used for tests only */
 };
 
 
 void luaT_init (lua_State *L) {
   static const char *const luaT_eventname[] = {  /* ORDER TM */
     "__index", "__newindex",
-    "__gc", "__mode", "__eq",
+    "__gc", "__mode", "__len", "__eq",
     "__add", "__sub", "__mul", "__div", "__mod",
-    "__pow", "__unm", "__len", "__lt", "__le",
+    "__pow", "__unm", "__lt", "__le",
     "__concat", "__call"
   };
   int i;
@@ -60,7 +62,7 @@ const TValue *luaT_gettm (Table *events, TMS event, TString *ename) {
 
 const TValue *luaT_gettmbyobj (lua_State *L, const TValue *o, TMS event) {
   Table *mt;
-  switch (ttype(o)) {
+  switch (ttypenv(o)) {
     case LUA_TTABLE:
       mt = hvalue(o)->metatable;
       break;
@@ -68,7 +70,7 @@ const TValue *luaT_gettmbyobj (lua_State *L, const TValue *o, TMS event) {
       mt = uvalue(o)->metatable;
       break;
     default:
-      mt = G(L)->mt[ttype(o)];
+      mt = G(L)->mt[ttypenv(o)];
   }
   return (mt ? luaH_getstr(mt, G(L)->tmname[event]) : luaO_nilobject);
 }
diff --git a/src/ltm.h b/src/ltm.h
index 64343b7..89bdc19 100644..100755
--- a/src/ltm.h
+++ b/src/ltm.h
@@ -1,5 +1,5 @@
 /*
-** $Id: ltm.h,v 2.6.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: ltm.h,v 2.11 2011/02/28 17:32:10 roberto Exp $
 ** Tag methods
 ** See Copyright Notice in lua.h
 */
@@ -20,6 +20,7 @@ typedef enum {
   TM_NEWINDEX,
   TM_GC,
   TM_MODE,
+  TM_LEN,
   TM_EQ,  /* last tag method with `fast' access */
   TM_ADD,
   TM_SUB,
@@ -28,7 +29,6 @@ typedef enum {
   TM_MOD,
   TM_POW,
   TM_UNM,
-  TM_LEN,
   TM_LT,
   TM_LE,
   TM_CONCAT,
@@ -43,7 +43,10 @@ typedef enum {
 
 #define fasttm(l,et,e)	gfasttm(G(l), et, e)
 
-LUAI_DATA const char *const luaT_typenames[];
+#define ttypename(x)	luaT_typenames_[(x) + 1]
+#define objtypename(x)	ttypename(ttypenv(x))
+
+LUAI_DDEC const char *const luaT_typenames_[LUA_TOTALTAGS];
 
 
 LUAI_FUNC const TValue *luaT_gettm (Table *events, TMS event, TString *ename);
diff --git a/src/lua.c b/src/lua.c
index 3a46609..8b317c6 100644..100755
--- a/src/lua.c
+++ b/src/lua.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lua.c,v 1.160.1.2 2007/12/28 15:32:23 roberto Exp $
+** $Id: lua.c,v 1.200 2011/06/16 14:30:58 roberto Exp $
 ** Lua stand-alone interpreter
 ** See Copyright Notice in lua.h
 */
@@ -18,6 +18,72 @@
 #include "lualib.h"
 
 
+#if !defined(LUA_PROMPT)
+#define LUA_PROMPT		"> "
+#define LUA_PROMPT2		">> "
+#endif
+
+#if !defined(LUA_PROGNAME)
+#define LUA_PROGNAME		"lua"
+#endif
+
+#if !defined(LUA_MAXINPUT)
+#define LUA_MAXINPUT		512
+#endif
+
+#if !defined(LUA_INIT)
+#define LUA_INIT		"LUA_INIT"
+#endif
+
+#define LUA_INITVERSION  \
+	LUA_INIT "_" LUA_VERSION_MAJOR "_" LUA_VERSION_MINOR
+
+
+/*
+** lua_stdin_is_tty detects whether the standard input is a 'tty' (that
+** is, whether we're running lua interactively).
+*/
+#if defined(LUA_USE_ISATTY)
+#include <unistd.h>
+#define lua_stdin_is_tty()      isatty(0)
+#elif defined(LUA_WIN)
+#include <io.h>
+#include <stdio.h>
+#define lua_stdin_is_tty()      _isatty(_fileno(stdin))
+#else
+#define lua_stdin_is_tty()      1  /* assume stdin is a tty */
+#endif
+
+
+/*
+** lua_readline defines how to show a prompt and then read a line from
+** the standard input.
+** lua_saveline defines how to "save" a read line in a "history".
+** lua_freeline defines how to free a line read by lua_readline.
+*/
+#if defined(LUA_USE_READLINE)
+
+#include <stdio.h>
+#include <readline/readline.h>
+#include <readline/history.h>
+#define lua_readline(L,b,p)     ((void)L, ((b)=readline(p)) != NULL)
+#define lua_saveline(L,idx) \
+        if (lua_rawlen(L,idx) > 0)  /* non-empty line? */ \
+          add_history(lua_tostring(L, idx));  /* add it to history */
+#define lua_freeline(L,b)       ((void)L, free(b))
+
+#elif !defined(lua_readline)
+
+#define lua_readline(L,b,p)     \
+        ((void)L, fputs(p, stdout), fflush(stdout),  /* show prompt */ \
+        fgets(b, LUA_MAXINPUT, stdin) != NULL)  /* get line */
+#define lua_saveline(L,idx)     { (void)L; (void)idx; }
+#define lua_freeline(L,b)       { (void)L; (void)b; }
+
+#endif
+
+
+
 
 static lua_State *globalL = NULL;
 
@@ -39,77 +105,86 @@ static void laction (int i) {
 }
 
 
-static void print_usage (void) {
-  fprintf(stderr,
-  "usage: %s [options] [script [args]].\n"
+static void print_usage (const char *badoption) {
+  luai_writestringerror("%s: ", progname);
+  if (badoption[1] == 'e' || badoption[1] == 'l')
+    luai_writestringerror("'%s' needs argument\n", badoption);
+  else
+    luai_writestringerror("unrecognized option '%s'\n", badoption);
+  luai_writestringerror(
+  "usage: %s [options] [script [args]]\n"
   "Available options are:\n"
   "  -e stat  execute string " LUA_QL("stat") "\n"
-  "  -l name  require library " LUA_QL("name") "\n"
   "  -i       enter interactive mode after executing " LUA_QL("script") "\n"
+  "  -l name  require library " LUA_QL("name") "\n"
   "  -v       show version information\n"
   "  --       stop handling options\n"
-  "  -        execute stdin and stop handling options\n"
+  "  -        stop handling options and execute stdin\n"
   ,
   progname);
-  fflush(stderr);
 }
 
 
 static void l_message (const char *pname, const char *msg) {
-  if (pname) fprintf(stderr, "%s: ", pname);
-  fprintf(stderr, "%s\n", msg);
-  fflush(stderr);
+  if (pname) luai_writestringerror("%s: ", pname);
+  luai_writestringerror("%s\n", msg);
 }
 
 
 static int report (lua_State *L, int status) {
-  if (status && !lua_isnil(L, -1)) {
+  if (status != LUA_OK && !lua_isnil(L, -1)) {
     const char *msg = lua_tostring(L, -1);
     if (msg == NULL) msg = "(error object is not a string)";
     l_message(progname, msg);
     lua_pop(L, 1);
+    /* force a complete garbage collection in case of errors */
+    lua_gc(L, LUA_GCCOLLECT, 0);
   }
   return status;
 }
 
 
-static int traceback (lua_State *L) {
-  if (!lua_isstring(L, 1))  /* 'message' not a string? */
-    return 1;  /* keep it intact */
-  lua_getfield(L, LUA_GLOBALSINDEX, "debug");
-  if (!lua_istable(L, -1)) {
+/* the next function is called unprotected, so it must avoid errors */
+static void finalreport (lua_State *L, int status) {
+  if (status != LUA_OK) {
+    const char *msg = (lua_type(L, -1) == LUA_TSTRING) ? lua_tostring(L, -1)
+                                                       : NULL;
+    if (msg == NULL) msg = "(error object is not a string)";
+    l_message(progname, msg);
     lua_pop(L, 1);
-    return 1;
   }
-  lua_getfield(L, -1, "traceback");
-  if (!lua_isfunction(L, -1)) {
-    lua_pop(L, 2);
-    return 1;
+}
+
+
+static int traceback (lua_State *L) {
+  const char *msg = lua_tostring(L, 1);
+  if (msg)
+    luaL_traceback(L, L, msg, 1);
+  else if (!lua_isnoneornil(L, 1)) {  /* is there an error object? */
+    if (!luaL_callmeta(L, 1, "__tostring"))  /* try its 'tostring' metamethod */
+      lua_pushliteral(L, "(no error message)");
   }
-  lua_pushvalue(L, 1);  /* pass error message */
-  lua_pushinteger(L, 2);  /* skip this function and traceback */
-  lua_call(L, 2, 1);  /* call debug.traceback */
   return 1;
 }
 
 
-static int docall (lua_State *L, int narg, int clear) {
+static int docall (lua_State *L, int narg, int nres) {
   int status;
   int base = lua_gettop(L) - narg;  /* function index */
   lua_pushcfunction(L, traceback);  /* push traceback function */
   lua_insert(L, base);  /* put it under chunk and args */
+  globalL = L;  /* to be available to 'laction' */
   signal(SIGINT, laction);
-  status = lua_pcall(L, narg, (clear ? 0 : LUA_MULTRET), base);
+  status = lua_pcall(L, narg, nres, base);
   signal(SIGINT, SIG_DFL);
   lua_remove(L, base);  /* remove traceback function */
-  /* force a complete garbage collection in case of errors */
-  if (status != 0) lua_gc(L, LUA_GCCOLLECT, 0);
   return status;
 }
 
 
 static void print_version (void) {
-  l_message(NULL, LUA_RELEASE "  " LUA_COPYRIGHT);
+  luai_writestring(LUA_COPYRIGHT, strlen(LUA_COPYRIGHT));
+  luai_writeline();
 }
 
 
@@ -132,40 +207,53 @@ static int getargs (lua_State *L, char **argv, int n) {
 
 
 static int dofile (lua_State *L, const char *name) {
-  int status = luaL_loadfile(L, name) || docall(L, 0, 1);
+  int status = luaL_loadfile(L, name);
+  if (status == LUA_OK) status = docall(L, 0, 0);
   return report(L, status);
 }
 
 
 static int dostring (lua_State *L, const char *s, const char *name) {
-  int status = luaL_loadbuffer(L, s, strlen(s), name) || docall(L, 0, 1);
+  int status = luaL_loadbuffer(L, s, strlen(s), name);
+  if (status == LUA_OK) status = docall(L, 0, 0);
   return report(L, status);
 }
 
 
 static int dolibrary (lua_State *L, const char *name) {
-  lua_getglobal(L, "require");
+  int status;
+  lua_pushglobaltable(L);
+  lua_getfield(L, -1, "require");
   lua_pushstring(L, name);
-  return report(L, docall(L, 1, 1));
+  status = docall(L, 1, 1);
+  if (status == LUA_OK) {
+    lua_setfield(L, -2, name);  /* global[name] = require return */
+    lua_pop(L, 1);  /* remove global table */
+  }
+  else
+    lua_remove(L, -2);  /* remove global table (below error msg.) */
+  return report(L, status);
 }
 
 
 static const char *get_prompt (lua_State *L, int firstline) {
   const char *p;
-  lua_getfield(L, LUA_GLOBALSINDEX, firstline ? "_PROMPT" : "_PROMPT2");
+  lua_getglobal(L, firstline ? "_PROMPT" : "_PROMPT2");
   p = lua_tostring(L, -1);
   if (p == NULL) p = (firstline ? LUA_PROMPT : LUA_PROMPT2);
   lua_pop(L, 1);  /* remove global */
   return p;
 }
 
+/* mark in error messages for incomplete statements */
+#define EOFMARK		"<eof>"
+#define marklen		(sizeof(EOFMARK)/sizeof(char) - 1)
 
 static int incomplete (lua_State *L, int status) {
   if (status == LUA_ERRSYNTAX) {
     size_t lmsg;
     const char *msg = lua_tolstring(L, -1, &lmsg);
-    const char *tp = msg + lmsg - (sizeof(LUA_QL("<eof>")) - 1);
-    if (strstr(msg, LUA_QL("<eof>")) == tp) {
+    if (lmsg >= marklen && strcmp(msg + lmsg - marklen, EOFMARK) == 0) {
       lua_pop(L, 1);
       return 1;
     }
@@ -199,7 +287,9 @@ static int loadline (lua_State *L) {
   if (!pushline(L, 1))
     return -1;  /* no input */
   for (;;) {  /* repeat until gets a complete line */
-    status = luaL_loadbuffer(L, lua_tostring(L, 1), lua_strlen(L, 1), "=stdin");
+    size_t l;
+    const char *line = lua_tolstring(L, 1, &l);
+    status = luaL_loadbuffer(L, line, l, "=stdin");
     if (!incomplete(L, status)) break;  /* cannot try to add lines? */
     if (!pushline(L, 0))  /* no more input? */
       return -1;
@@ -218,20 +308,20 @@ static void dotty (lua_State *L) {
   const char *oldprogname = progname;
   progname = NULL;
   while ((status = loadline(L)) != -1) {
-    if (status == 0) status = docall(L, 0, 0);
+    if (status == LUA_OK) status = docall(L, 0, LUA_MULTRET);
     report(L, status);
-    if (status == 0 && lua_gettop(L) > 0) {  /* any result to print? */
+    if (status == LUA_OK && lua_gettop(L) > 0) {  /* any result to print? */
+      luaL_checkstack(L, LUA_MINSTACK, "too many results to print");
       lua_getglobal(L, "print");
       lua_insert(L, 1);
-      if (lua_pcall(L, lua_gettop(L)-1, 0, 0) != 0)
+      if (lua_pcall(L, lua_gettop(L)-1, 0, 0) != LUA_OK)
         l_message(progname, lua_pushfstring(L,
                                "error calling " LUA_QL("print") " (%s)",
                                lua_tostring(L, -1)));
     }
   }
   lua_settop(L, 0);  /* clear stack */
-  fputs("\n", stdout);
-  fflush(stdout);
+  luai_writeline();
   progname = oldprogname;
 }
 
@@ -242,20 +332,20 @@ static int handle_script (lua_State *L, char **argv, int n) {
   int narg = getargs(L, argv, n);  /* collect arguments */
   lua_setglobal(L, "arg");
   fname = argv[n];
-  if (strcmp(fname, "-") == 0 && strcmp(argv[n-1], "--") != 0) 
+  if (strcmp(fname, "-") == 0 && strcmp(argv[n-1], "--") != 0)
     fname = NULL;  /* stdin */
   status = luaL_loadfile(L, fname);
   lua_insert(L, -(narg+1));
-  if (status == 0)
-    status = docall(L, narg, 0);
+  if (status == LUA_OK)
+    status = docall(L, narg, LUA_MULTRET);
   else
-    lua_pop(L, narg);      
+    lua_pop(L, narg);
   return report(L, status);
 }
 
 
 /* check that argument has no extra characters at the end */
-#define notail(x)	{if ((x)[2] != '\0') return -1;}
+#define noextrachars(x)		{if ((x)[2] != '\0') return -1;}
 
 
 static int collectargs (char **argv, int *pi, int *pv, int *pe) {
@@ -265,26 +355,28 @@ static int collectargs (char **argv, int *pi, int *pv, int *pe) {
         return i;
     switch (argv[i][1]) {  /* option */
       case '-':
-        notail(argv[i]);
+        noextrachars(argv[i]);
         return (argv[i+1] != NULL ? i+1 : 0);
       case '\0':
         return i;
       case 'i':
-        notail(argv[i]);
+        noextrachars(argv[i]);
         *pi = 1;  /* go through */
       case 'v':
-        notail(argv[i]);
+        noextrachars(argv[i]);
         *pv = 1;
         break;
       case 'e':
         *pe = 1;  /* go through */
-      case 'l':
-        if (argv[i][2] == '\0') {
-          i++;
-          if (argv[i] == NULL) return -1;
+      case 'l':  /* both options need an argument */
+        if (argv[i][2] == '\0') {  /* no concatenated argument? */
+          i++;  /* try next 'argv' */
+          if (argv[i] == NULL || argv[i][0] == '-')
+            return -(i - 1);  /* no next argument or it is another option */
         }
         break;
-      default: return -1;  /* invalid option */
+      default:  /* invalid option; return its index... */
+        return -i;  /* ...as a negative value */
     }
   }
   return 0;
@@ -294,99 +386,98 @@ static int collectargs (char **argv, int *pi, int *pv, int *pe) {
 static int runargs (lua_State *L, char **argv, int n) {
   int i;
   for (i = 1; i < n; i++) {
-    if (argv[i] == NULL) continue;
     lua_assert(argv[i][0] == '-');
     switch (argv[i][1]) {  /* option */
       case 'e': {
         const char *chunk = argv[i] + 2;
         if (*chunk == '\0') chunk = argv[++i];
         lua_assert(chunk != NULL);
-        if (dostring(L, chunk, "=(command line)") != 0)
-          return 1;
+        if (dostring(L, chunk, "=(command line)") != LUA_OK)
+          return 0;
         break;
       }
       case 'l': {
         const char *filename = argv[i] + 2;
         if (*filename == '\0') filename = argv[++i];
         lua_assert(filename != NULL);
-        if (dolibrary(L, filename))
-          return 1;  /* stop if file fails */
+        if (dolibrary(L, filename) != LUA_OK)
+          return 0;  /* stop if file fails */
         break;
       }
       default: break;
     }
   }
-  return 0;
+  return 1;
 }
 
 
 static int handle_luainit (lua_State *L) {
-  const char *init = getenv(LUA_INIT);
-  if (init == NULL) return 0;  /* status OK */
+  const char *name = "=" LUA_INITVERSION;
+  const char *init = getenv(name + 1);
+  if (init == NULL) {
+    name = "=" LUA_INIT;
+    init = getenv(name + 1);  /* try alternative name */
+  }
+  if (init == NULL) return LUA_OK;
   else if (init[0] == '@')
     return dofile(L, init+1);
   else
-    return dostring(L, init, "=" LUA_INIT);
+    return dostring(L, init, name);
 }
 
 
-struct Smain {
-  int argc;
-  char **argv;
-  int status;
-};
-
-
 static int pmain (lua_State *L) {
-  struct Smain *s = (struct Smain *)lua_touserdata(L, 1);
-  char **argv = s->argv;
+  int argc = (int)lua_tointeger(L, 1);
+  char **argv = (char **)lua_touserdata(L, 2);
   int script;
   int has_i = 0, has_v = 0, has_e = 0;
-  globalL = L;
   if (argv[0] && argv[0][0]) progname = argv[0];
-  lua_gc(L, LUA_GCSTOP, 0);  /* stop collector during initialization */
-  luaL_openlibs(L);  /* open libraries */
-  lua_gc(L, LUA_GCRESTART, 0);
-  s->status = handle_luainit(L);
-  if (s->status != 0) return 0;
   script = collectargs(argv, &has_i, &has_v, &has_e);
-  if (script < 0) {  /* invalid args? */
-    print_usage();
-    s->status = 1;
+  if (script < 0) {  /* invalid arg? */
+    print_usage(argv[-script]);
     return 0;
   }
   if (has_v) print_version();
-  s->status = runargs(L, argv, (script > 0) ? script : s->argc);
-  if (s->status != 0) return 0;
-  if (script)
-    s->status = handle_script(L, argv, script);
-  if (s->status != 0) return 0;
-  if (has_i)
+  /* open standard libraries */
+  luaL_checkversion(L);
+  lua_gc(L, LUA_GCSTOP, 0);  /* stop collector during initialization */
+  luaL_openlibs(L);  /* open libraries */
+  lua_gc(L, LUA_GCRESTART, 0);
+  /* run LUA_INIT */
+  if (handle_luainit(L) != LUA_OK) return 0;
+  /* execute arguments -e and -l */
+  if (!runargs(L, argv, (script > 0) ? script : argc)) return 0;
+  /* execute main script (if there is one) */
+  if (script && handle_script(L, argv, script) != LUA_OK) return 0;
+  if (has_i)  /* -i option? */
     dotty(L);
-  else if (script == 0 && !has_e && !has_v) {
+  else if (script == 0 && !has_e && !has_v) {  /* no arguments? */
     if (lua_stdin_is_tty()) {
       print_version();
       dotty(L);
     }
     else dofile(L, NULL);  /* executes stdin as a file */
   }
-  return 0;
+  lua_pushboolean(L, 1);  /* signal no errors */
+  return 1;
 }
 
 
 int main (int argc, char **argv) {
-  int status;
-  struct Smain s;
-  lua_State *L = lua_open();  /* create state */
+  int status, result;
+  lua_State *L = luaL_newstate();  /* create state */
   if (L == NULL) {
     l_message(argv[0], "cannot create state: not enough memory");
     return EXIT_FAILURE;
   }
-  s.argc = argc;
-  s.argv = argv;
-  status = lua_cpcall(L, &pmain, &s);
-  report(L, status);
+  /* call 'pmain' in protected mode */
+  lua_pushcfunction(L, &pmain);
+  lua_pushinteger(L, argc);  /* 1st argument */
+  lua_pushlightuserdata(L, argv); /* 2nd argument */
+  status = lua_pcall(L, 2, 1, 0);
+  result = lua_toboolean(L, -1);  /* get result */
+  finalreport(L, status);
   lua_close(L);
-  return (status || s.status) ? EXIT_FAILURE : EXIT_SUCCESS;
+  return (result && status == LUA_OK) ? EXIT_SUCCESS : EXIT_FAILURE;
 }
 
diff --git a/src/lua.def b/src/lua.def
deleted file mode 100644
index 5870586..0000000
--- a/src/lua.def
+++ /dev/null
@@ -1,131 +0,0 @@
-EXPORTS

-  lua_tolstring

-  lua_typename

-  lua_pushfstring

-  lua_pushvfstring

-  lua_getlocal

-  lua_getupvalue

-  lua_setlocal

-  lua_setupvalue

-  lua_topointer

-  lua_iscfunction

-  lua_isnumber

-  lua_isstring

-  lua_isuserdata

-  lua_toboolean

-  lua_type

-  lua_equal

-  lua_lessthan

-  lua_rawequal

-  lua_checkstack

-  lua_cpcall

-  lua_error

-  lua_getmetatable

-  lua_gettop

-  lua_load

-  lua_next

-  lua_pcall

-  lua_pushthread

-  lua_setfenv

-  lua_setmetatable

-  lua_resume

-  lua_status

-  lua_yield

-  lua_dump

-  lua_gc

-  lua_gethook

-  lua_gethookcount

-  lua_gethookmask

-  lua_getinfo

-  lua_getstack

-  lua_sethook

-  lua_getallocf

-  lua_tocfunction

-  lua_atpanic

-  lua_tointeger

-  lua_tonumber

-  lua_tothread

-  lua_newstate

-  lua_newthread

-  lua_objlen

-  lua_touserdata

-  lua_close

-  lua_call

-  lua_concat

-  lua_createtable

-  lua_getfenv

-  lua_getfield

-  lua_gettable

-  lua_insert

-  lua_pushboolean

-  lua_pushcclosure

-  lua_pushinteger

-  lua_pushlightuserdata

-  lua_pushlstring

-  lua_pushnil

-  lua_pushnumber

-  lua_pushstring

-  lua_pushvalue

-  lua_rawget

-  lua_rawgeti

-  lua_rawset

-  lua_rawseti

-  lua_remove

-  lua_replace

-  lua_setfield

-  lua_settable

-  lua_settop

-  lua_xmove

-  lua_newuserdata

-  lua_setallocf

-  luaL_prepbuffer

-  luaL_checklstring

-  luaL_findtable

-  luaL_gsub

-  luaL_optlstring

-  luaL_newmetatable

-  luaL_argerror

-  luaL_callmeta

-  luaL_checkoption

-  luaL_error

-  luaL_getmetafield

-  luaL_loadbuffer

-  luaL_loadfile

-  luaL_loadstring

-  luaL_ref

-  luaL_typerror

-  luaL_checkinteger

-  luaL_optinteger

-  luaL_checknumber

-  luaL_optnumber

-  luaL_newstate

-  luaL_openlib

-  luaL_addlstring

-  luaL_addstring

-  luaL_addvalue

-  luaL_buffinit

-  luaL_checkany

-  luaL_checkstack

-  luaL_checktype

-  luaL_pushresult

-  luaL_register

-  luaL_unref

-  luaL_where

-  luaL_checkudata

-  luaopen_base

-  luaopen_debug

-  luaopen_io

-  luaopen_math

-  luaopen_os

-  luaopen_package

-  luaopen_string

-  luaopen_table

-  luaL_openlibs

-  luaU_dump

-  luaM_toobig

-  luaM_realloc_

-  luaS_newlstr

-  luaD_growstack

-  luaF_newproto

-  luaP_opmodes

-  luaP_opnames

diff --git a/src/lua.h b/src/lua.h
index e4bdfd3..518d44c 100644..100755
--- a/src/lua.h
+++ b/src/lua.h
@@ -1,6 +1,6 @@
 /*
-** $Id: lua.h,v 1.218.1.5 2008/08/06 13:30:12 roberto Exp $
-** Lua - An Extensible Extension Language
+** $Id: lua.h,v 1.278 2011/07/02 16:00:15 roberto Exp $
+** Lua - A Scripting Language
 ** Lua.org, PUC-Rio, Brazil (http://www.lua.org)
 ** See Copyright Notice at the end of this file
 */
@@ -16,35 +16,39 @@
 #include "luaconf.h"
 
 
-#define LUA_VERSION	"Lua 5.1"
-#define LUA_RELEASE	"Lua 5.1.4"
-#define LUA_VERSION_NUM	501
-#define LUA_COPYRIGHT	"Copyright (C) 1994-2008 Lua.org, PUC-Rio"
-#define LUA_AUTHORS 	"R. Ierusalimschy, L. H. de Figueiredo & W. Celes"
+#define LUA_VERSION_MAJOR	"5"
+#define LUA_VERSION_MINOR	"2"
+#define LUA_VERSION_NUM		502
+#define LUA_VERSION_RELEASE	"0" " (beta)"
 
+#define LUA_VERSION	"Lua " LUA_VERSION_MAJOR "." LUA_VERSION_MINOR
+#define LUA_RELEASE	LUA_VERSION "." LUA_VERSION_RELEASE
+#define LUA_COPYRIGHT	LUA_RELEASE "  Copyright (C) 1994-2011 Lua.org, PUC-Rio"
+#define LUA_AUTHORS	"R. Ierusalimschy, L. H. de Figueiredo, W. Celes"
 
-/* mark for precompiled code (`<esc>Lua') */
-#define	LUA_SIGNATURE	"\033Lua"
 
-/* option for multiple returns in `lua_pcall' and `lua_call' */
+/* mark for precompiled code ('<esc>Lua') */
+#define LUA_SIGNATURE	"\033Lua"
+
+/* option for multiple returns in 'lua_pcall' and 'lua_call' */
 #define LUA_MULTRET	(-1)
 
 
 /*
 ** pseudo-indices
 */
-#define LUA_REGISTRYINDEX	(-10000)
-#define LUA_ENVIRONINDEX	(-10001)
-#define LUA_GLOBALSINDEX	(-10002)
-#define lua_upvalueindex(i)	(LUA_GLOBALSINDEX-(i))
+#define LUA_REGISTRYINDEX	LUAI_FIRSTPSEUDOIDX
+#define lua_upvalueindex(i)	(LUA_REGISTRYINDEX - (i))
 
 
-/* thread status; 0 is OK */
+/* thread status */
+#define LUA_OK		0
 #define LUA_YIELD	1
 #define LUA_ERRRUN	2
 #define LUA_ERRSYNTAX	3
 #define LUA_ERRMEM	4
-#define LUA_ERRERR	5
+#define LUA_ERRGCMM	5
+#define LUA_ERRERR	6
 
 
 typedef struct lua_State lua_State;
@@ -81,18 +85,18 @@ typedef void * (*lua_Alloc) (void *ud, void *ptr, size_t osize, size_t nsize);
 #define LUA_TUSERDATA		7
 #define LUA_TTHREAD		8
 
+#define LUA_NUMTAGS		9
+
 
 
 /* minimum Lua stack available to a C function */
 #define LUA_MINSTACK	20
 
 
-/*
-** generic extra include file
-*/
-#if defined(LUA_USER_H)
-#include LUA_USER_H
-#endif
+/* predefined values in the registry */
+#define LUA_RIDX_MAINTHREAD	1
+#define LUA_RIDX_GLOBALS	2
+#define LUA_RIDX_LAST		LUA_RIDX_GLOBALS
 
 
 /* type of numbers in Lua */
@@ -102,6 +106,18 @@ typedef LUA_NUMBER lua_Number;
 /* type for integer functions */
 typedef LUA_INTEGER lua_Integer;
 
+/* unsigned integer type */
+typedef LUA_UNSIGNED lua_Unsigned;
+
+
+
+/*
+** generic extra include file
+*/
+#if defined(LUA_USER_H)
+#include LUA_USER_H
+#endif
+
 
 
 /*
@@ -114,15 +130,20 @@ LUA_API lua_State *(lua_newthread) (lua_State *L);
 LUA_API lua_CFunction (lua_atpanic) (lua_State *L, lua_CFunction panicf);
 
 
+LUA_API const lua_Number *(lua_version) (lua_State *L);
+
+
 /*
 ** basic stack manipulation
 */
+LUA_API int   (lua_absindex) (lua_State *L, int idx);
 LUA_API int   (lua_gettop) (lua_State *L);
 LUA_API void  (lua_settop) (lua_State *L, int idx);
 LUA_API void  (lua_pushvalue) (lua_State *L, int idx);
 LUA_API void  (lua_remove) (lua_State *L, int idx);
 LUA_API void  (lua_insert) (lua_State *L, int idx);
 LUA_API void  (lua_replace) (lua_State *L, int idx);
+LUA_API void  (lua_copy) (lua_State *L, int fromidx, int toidx);
 LUA_API int   (lua_checkstack) (lua_State *L, int sz);
 
 LUA_API void  (lua_xmove) (lua_State *from, lua_State *to, int n);
@@ -139,15 +160,12 @@ LUA_API int             (lua_isuserdata) (lua_State *L, int idx);
 LUA_API int             (lua_type) (lua_State *L, int idx);
 LUA_API const char     *(lua_typename) (lua_State *L, int tp);
 
-LUA_API int            (lua_equal) (lua_State *L, int idx1, int idx2);
-LUA_API int            (lua_rawequal) (lua_State *L, int idx1, int idx2);
-LUA_API int            (lua_lessthan) (lua_State *L, int idx1, int idx2);
-
-LUA_API lua_Number      (lua_tonumber) (lua_State *L, int idx);
-LUA_API lua_Integer     (lua_tointeger) (lua_State *L, int idx);
+LUA_API lua_Number      (lua_tonumberx) (lua_State *L, int idx, int *isnum);
+LUA_API lua_Integer     (lua_tointegerx) (lua_State *L, int idx, int *isnum);
+LUA_API lua_Unsigned    (lua_tounsignedx) (lua_State *L, int idx, int *isnum);
 LUA_API int             (lua_toboolean) (lua_State *L, int idx);
 LUA_API const char     *(lua_tolstring) (lua_State *L, int idx, size_t *len);
-LUA_API size_t          (lua_objlen) (lua_State *L, int idx);
+LUA_API size_t          (lua_rawlen) (lua_State *L, int idx);
 LUA_API lua_CFunction   (lua_tocfunction) (lua_State *L, int idx);
 LUA_API void	       *(lua_touserdata) (lua_State *L, int idx);
 LUA_API lua_State      *(lua_tothread) (lua_State *L, int idx);
@@ -155,13 +173,36 @@ LUA_API const void     *(lua_topointer) (lua_State *L, int idx);
 
 
 /*
+** Comparison and arithmetic functions
+*/
+
+#define LUA_OPADD	0	/* ORDER TM */
+#define LUA_OPSUB	1
+#define LUA_OPMUL	2
+#define LUA_OPDIV	3
+#define LUA_OPMOD	4
+#define LUA_OPPOW	5
+#define LUA_OPUNM	6
+
+LUA_API void  (lua_arith) (lua_State *L, int op);
+
+#define LUA_OPEQ	0
+#define LUA_OPLT	1
+#define LUA_OPLE	2
+
+LUA_API int   (lua_rawequal) (lua_State *L, int idx1, int idx2);
+LUA_API int   (lua_compare) (lua_State *L, int idx1, int idx2, int op);
+
+
+/*
 ** push functions (C -> stack)
 */
-LUA_API void  (lua_pushnil) (lua_State *L);
-LUA_API void  (lua_pushnumber) (lua_State *L, lua_Number n);
-LUA_API void  (lua_pushinteger) (lua_State *L, lua_Integer n);
-LUA_API void  (lua_pushlstring) (lua_State *L, const char *s, size_t l);
-LUA_API void  (lua_pushstring) (lua_State *L, const char *s);
+LUA_API void        (lua_pushnil) (lua_State *L);
+LUA_API void        (lua_pushnumber) (lua_State *L, lua_Number n);
+LUA_API void        (lua_pushinteger) (lua_State *L, lua_Integer n);
+LUA_API void        (lua_pushunsigned) (lua_State *L, lua_Unsigned n);
+LUA_API const char *(lua_pushlstring) (lua_State *L, const char *s, size_t l);
+LUA_API const char *(lua_pushstring) (lua_State *L, const char *s);
 LUA_API const char *(lua_pushvfstring) (lua_State *L, const char *fmt,
                                                       va_list argp);
 LUA_API const char *(lua_pushfstring) (lua_State *L, const char *fmt, ...);
@@ -181,7 +222,7 @@ LUA_API void  (lua_rawgeti) (lua_State *L, int idx, int n);
 LUA_API void  (lua_createtable) (lua_State *L, int narr, int nrec);
 LUA_API void *(lua_newuserdata) (lua_State *L, size_t sz);
 LUA_API int   (lua_getmetatable) (lua_State *L, int objindex);
-LUA_API void  (lua_getfenv) (lua_State *L, int idx);
+LUA_API void  (lua_getuservalue) (lua_State *L, int idx);
 
 
 /*
@@ -192,15 +233,22 @@ LUA_API void  (lua_setfield) (lua_State *L, int idx, const char *k);
 LUA_API void  (lua_rawset) (lua_State *L, int idx);
 LUA_API void  (lua_rawseti) (lua_State *L, int idx, int n);
 LUA_API int   (lua_setmetatable) (lua_State *L, int objindex);
-LUA_API int   (lua_setfenv) (lua_State *L, int idx);
+LUA_API void  (lua_setuservalue) (lua_State *L, int idx);
 
 
 /*
-** `load' and `call' functions (load and run Lua code)
+** 'load' and 'call' functions (load and run Lua code)
 */
-LUA_API void  (lua_call) (lua_State *L, int nargs, int nresults);
-LUA_API int   (lua_pcall) (lua_State *L, int nargs, int nresults, int errfunc);
-LUA_API int   (lua_cpcall) (lua_State *L, lua_CFunction func, void *ud);
+LUA_API void  (lua_callk) (lua_State *L, int nargs, int nresults, int ctx,
+                           lua_CFunction k);
+#define lua_call(L,n,r)		lua_callk(L, (n), (r), 0, NULL)
+
+LUA_API int   (lua_getctx) (lua_State *L, int *ctx);
+
+LUA_API int   (lua_pcallk) (lua_State *L, int nargs, int nresults, int errfunc,
+                            int ctx, lua_CFunction k);
+#define lua_pcall(L,n,r,f)	lua_pcallk(L, (n), (r), (f), 0, NULL)
+
 LUA_API int   (lua_load) (lua_State *L, lua_Reader reader, void *dt,
                                         const char *chunkname);
 
@@ -210,7 +258,9 @@ LUA_API int (lua_dump) (lua_State *L, lua_Writer writer, void *data);
 /*
 ** coroutine functions
 */
-LUA_API int  (lua_yield) (lua_State *L, int nresults);
+LUA_API int  (lua_yieldk) (lua_State *L, int nresults, int ctx,
+                           lua_CFunction k);
+#define lua_yield(L,n)		lua_yieldk(L, (n), 0, NULL)
 LUA_API int  (lua_resume) (lua_State *L, int narg);
 LUA_API int  (lua_status) (lua_State *L);
 
@@ -226,6 +276,10 @@ LUA_API int  (lua_status) (lua_State *L);
 #define LUA_GCSTEP		5
 #define LUA_GCSETPAUSE		6
 #define LUA_GCSETSTEPMUL	7
+#define LUA_GCSETMAJORINC	8
+#define LUA_GCISRUNNING		9
+#define LUA_GCGEN		10
+#define LUA_GCINC		11
 
 LUA_API int (lua_gc) (lua_State *L, int what, int data);
 
@@ -239,28 +293,38 @@ LUA_API int   (lua_error) (lua_State *L);
 LUA_API int   (lua_next) (lua_State *L, int idx);
 
 LUA_API void  (lua_concat) (lua_State *L, int n);
+LUA_API void  (lua_len)    (lua_State *L, int idx);
 
 LUA_API lua_Alloc (lua_getallocf) (lua_State *L, void **ud);
-LUA_API void lua_setallocf (lua_State *L, lua_Alloc f, void *ud);
+LUA_API void      (lua_setallocf) (lua_State *L, lua_Alloc f, void *ud);
 
 
 
-/* 
+/*
 ** ===============================================================
 ** some useful macros
 ** ===============================================================
 */
 
+#define lua_tonumber(L,i)	lua_tonumberx(L,i,NULL)
+#define lua_tointeger(L,i)	lua_tointegerx(L,i,NULL)
+#define lua_tounsigned(L,i)	lua_tounsignedx(L,i,NULL)
+
 #define lua_pop(L,n)		lua_settop(L, -(n)-1)
 
 #define lua_newtable(L)		lua_createtable(L, 0, 0)
 
+#define lua_setglobal(L,s)  \
+	(lua_pushglobaltable(L), lua_pushvalue(L, -2), \
+	 lua_setfield(L, -2, (s)), lua_pop(L, 2))
+
+#define lua_getglobal(L,s) \
+	(lua_pushglobaltable(L), lua_getfield(L, -1, (s)), lua_remove(L, -2))
+
 #define lua_register(L,n,f) (lua_pushcfunction(L, (f)), lua_setglobal(L, (n)))
 
 #define lua_pushcfunction(L,f)	lua_pushcclosure(L, (f), 0)
 
-#define lua_strlen(L,i)		lua_objlen(L, (i))
-
 #define lua_isfunction(L,n)	(lua_type(L, (n)) == LUA_TFUNCTION)
 #define lua_istable(L,n)	(lua_type(L, (n)) == LUA_TTABLE)
 #define lua_islightuserdata(L,n)	(lua_type(L, (n)) == LUA_TLIGHTUSERDATA)
@@ -273,32 +337,14 @@ LUA_API void lua_setallocf (lua_State *L, lua_Alloc f, void *ud);
 #define lua_pushliteral(L, s)	\
 	lua_pushlstring(L, "" s, (sizeof(s)/sizeof(char))-1)
 
-#define lua_setglobal(L,s)	lua_setfield(L, LUA_GLOBALSINDEX, (s))
-#define lua_getglobal(L,s)	lua_getfield(L, LUA_GLOBALSINDEX, (s))
+#define lua_pushglobaltable(L)  \
+	lua_rawgeti(L, LUA_REGISTRYINDEX, LUA_RIDX_GLOBALS)
 
 #define lua_tostring(L,i)	lua_tolstring(L, (i), NULL)
 
 
 
 /*
-** compatibility macros and functions
-*/
-
-#define lua_open()	luaL_newstate()
-
-#define lua_getregistry(L)	lua_pushvalue(L, LUA_REGISTRYINDEX)
-
-#define lua_getgccount(L)	lua_gc(L, LUA_GCCOUNT, 0)
-
-#define lua_Chunkreader		lua_Reader
-#define lua_Chunkwriter		lua_Writer
-
-
-/* hack */
-LUA_API void lua_setlevel	(lua_State *from, lua_State *to);
-
-
-/*
 ** {======================================================================
 ** Debug API
 ** =======================================================================
@@ -312,7 +358,7 @@ LUA_API void lua_setlevel	(lua_State *from, lua_State *to);
 #define LUA_HOOKRET	1
 #define LUA_HOOKLINE	2
 #define LUA_HOOKCOUNT	3
-#define LUA_HOOKTAILRET 4
+#define LUA_HOOKTAILCALL 4
 
 
 /*
@@ -326,43 +372,50 @@ LUA_API void lua_setlevel	(lua_State *from, lua_State *to);
 typedef struct lua_Debug lua_Debug;  /* activation record */
 
 
-/* Functions to be called by the debuger in specific events */
+/* Functions to be called by the debugger in specific events */
 typedef void (*lua_Hook) (lua_State *L, lua_Debug *ar);
 
 
-LUA_API int lua_getstack (lua_State *L, int level, lua_Debug *ar);
-LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar);
-LUA_API const char *lua_getlocal (lua_State *L, const lua_Debug *ar, int n);
-LUA_API const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n);
-LUA_API const char *lua_getupvalue (lua_State *L, int funcindex, int n);
-LUA_API const char *lua_setupvalue (lua_State *L, int funcindex, int n);
+LUA_API int (lua_getstack) (lua_State *L, int level, lua_Debug *ar);
+LUA_API int (lua_getinfo) (lua_State *L, const char *what, lua_Debug *ar);
+LUA_API const char *(lua_getlocal) (lua_State *L, const lua_Debug *ar, int n);
+LUA_API const char *(lua_setlocal) (lua_State *L, const lua_Debug *ar, int n);
+LUA_API const char *(lua_getupvalue) (lua_State *L, int funcindex, int n);
+LUA_API const char *(lua_setupvalue) (lua_State *L, int funcindex, int n);
+
+LUA_API void *(lua_upvalueid) (lua_State *L, int fidx, int n);
+LUA_API void  (lua_upvaluejoin) (lua_State *L, int fidx1, int n1,
+                                               int fidx2, int n2);
 
-LUA_API int lua_sethook (lua_State *L, lua_Hook func, int mask, int count);
-LUA_API lua_Hook lua_gethook (lua_State *L);
-LUA_API int lua_gethookmask (lua_State *L);
-LUA_API int lua_gethookcount (lua_State *L);
+LUA_API int (lua_sethook) (lua_State *L, lua_Hook func, int mask, int count);
+LUA_API lua_Hook (lua_gethook) (lua_State *L);
+LUA_API int (lua_gethookmask) (lua_State *L);
+LUA_API int (lua_gethookcount) (lua_State *L);
 
 
 struct lua_Debug {
   int event;
   const char *name;	/* (n) */
-  const char *namewhat;	/* (n) `global', `local', `field', `method' */
-  const char *what;	/* (S) `Lua', `C', `main', `tail' */
+  const char *namewhat;	/* (n) 'global', 'local', 'field', 'method' */
+  const char *what;	/* (S) 'Lua', 'C', 'main', 'tail' */
   const char *source;	/* (S) */
   int currentline;	/* (l) */
-  int nups;		/* (u) number of upvalues */
   int linedefined;	/* (S) */
   int lastlinedefined;	/* (S) */
+  unsigned char nups;	/* (u) number of upvalues */
+  unsigned char nparams;/* (u) number of parameters */
+  char isvararg;        /* (u) */
+  char istailcall;	/* (t) */
   char short_src[LUA_IDSIZE]; /* (S) */
   /* private part */
-  int i_ci;  /* active function */
+  struct CallInfo *i_ci;  /* active function */
 };
 
 /* }====================================================================== */
 
 
 /******************************************************************************
-* Copyright (C) 1994-2008 Lua.org, PUC-Rio.  All rights reserved.
+* Copyright (C) 1994-2011 Lua.org, PUC-Rio.  All rights reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
diff --git a/etc/lua.hpp b/src/lua.hpp
index ec417f5..ec417f5 100644..100755
--- a/etc/lua.hpp
+++ b/src/lua.hpp
diff --git a/src/lua.rc b/src/lua.rc
index 893807a..7654186 100644
--- a/src/lua.rc
+++ b/src/lua.rc
@@ -1,8 +1,8 @@
 0  ICON  "..\\etc\\lua.ico"

 

 1 VERSIONINFO

- FILEVERSION 5,1,4,0

- PRODUCTVERSION 5,1,4,0

+ FILEVERSION 5,2,0,0

+ PRODUCTVERSION 5,2,0,0

 BEGIN

     BLOCK "StringFileInfo"

     BEGIN

@@ -11,12 +11,12 @@ BEGIN
             VALUE "Comments", "www.lua.org\0"

             VALUE "CompanyName", "Lua.org\0"

             VALUE "FileDescription", "Lua Console Standalone Interpreter\0"

-            VALUE "FileVersion", "5.1.4\0"

-            VALUE "LegalCopyright", "Copyright © 1994-2008 Lua.org, PUC-Rio.\0"

-            VALUE "OriginalFilename", "lua5.1.exe\0"

+            VALUE "FileVersion", "5.2.0-beta\0"

+            VALUE "LegalCopyright", "Copyright © 1994-2011 Lua.org, PUC-Rio.\0"

+            VALUE "OriginalFilename", "lua.exe\0"

             VALUE "ProductName", "Lua - The Programming Language\0"

-            VALUE "ProductVersion", "5.1.4\0"

-            VALUE "PrivateBuild", "Built for LuaDist\0"

+            VALUE "ProductVersion", "5.2.0-beta\0"

+            VALUE "PrivateBuild", "Built using LuaDist\0"

         END

     END

 END

diff --git a/src/lua_dll.rc b/src/lua_dll.rc
deleted file mode 100644
index fce29d9..0000000
--- a/src/lua_dll.rc
+++ /dev/null
@@ -1,26 +0,0 @@
-1 VERSIONINFO

- FILEVERSION 5,1,4,0

- PRODUCTVERSION 5,1,4,0

-BEGIN

-    BLOCK "StringFileInfo"

-    BEGIN

-        BLOCK "040904b0"

-        BEGIN

-            VALUE "Comments", "www.lua.org\0"

-            VALUE "CompanyName", "Lua.org\0"

-            VALUE "FileDescription", "Lua Language Run Time\0"

-            VALUE "FileVersion", "5.1.4\0"

-            VALUE "LegalCopyright", "Copyright © 1994-2009 Lua.org, PUC-Rio.\0"

-            VALUE "OriginalFilename", "lua5.1.dll\0"

-            VALUE "ProductName", "Lua - The Programming Language\0"

-            VALUE "ProductVersion", "5.1.4\0"

-            VALUE "PrivateBuild", "Built for LuaDist\0"

-        END

-    END

-END

-

-#ifdef MSVC8

-2 24 "lua_dll8.manifest"

-#elif MSVC9

-2 24 "lua_dll9.manifest"

-#endif

diff --git a/src/luac.c b/src/luac.c
index d070173..62ff9cc 100644..100755
--- a/src/luac.c
+++ b/src/luac.c
@@ -1,5 +1,5 @@
 /*
-** $Id: luac.c,v 1.54 2006/06/02 17:37:11 lhf Exp $
+** $Id: luac.c,v 1.67 2011/06/21 12:29:00 lhf Exp $
 ** Lua compiler (saves bytecodes to files; also list bytecodes)
 ** See Copyright Notice in lua.h
 */
@@ -15,16 +15,15 @@
 #include "lua.h"
 #include "lauxlib.h"
 
-#include "ldo.h"
-#include "lfunc.h"
-#include "lmem.h"
 #include "lobject.h"
-#include "lopcodes.h"
-#include "lstring.h"
+#include "lstate.h"
 #include "lundump.h"
 
+static void PrintFunction(const Proto* f, int full);
+#define luaU_print	PrintFunction
+
 #define PROGNAME	"luac"		/* default program name */
-#define	OUTPUT		PROGNAME ".out"	/* default output file */
+#define OUTPUT		PROGNAME ".out"	/* default output file */
 
 static int listing=0;			/* list bytecodes? */
 static int dumping=1;			/* dump bytecodes? */
@@ -52,20 +51,20 @@ static void usage(const char* message)
  else
   fprintf(stderr,"%s: %s\n",progname,message);
  fprintf(stderr,
- "usage: %s [options] [filenames].\n"
- "Available options are:\n"
- "  -        process stdin\n"
- "  -l       list\n"
- "  -o name  output to file " LUA_QL("name") " (default is \"%s\")\n"
- "  -p       parse only\n"
- "  -s       strip debug information\n"
- "  -v       show version information\n"
- "  --       stop handling options\n",
- progname,Output);
+  "usage: %s [options] [filenames]\n"
+  "Available options are:\n"
+  "  -l       list\n"
+  "  -o name  output to file " LUA_QL("name") " (default is \"%s\")\n"
+  "  -p       parse only\n"
+  "  -s       strip debug information\n"
+  "  -v       show version information\n"
+  "  --       stop handling options\n"
+  "  -        stop handling options and process stdin\n"
+  ,progname,Output);
  exit(EXIT_FAILURE);
 }
 
-#define	IS(s)	(strcmp(argv[i],s)==0)
+#define IS(s)	(strcmp(argv[i],s)==0)
 
 static int doargs(int argc, char* argv[])
 {
@@ -89,7 +88,8 @@ static int doargs(int argc, char* argv[])
   else if (IS("-o"))			/* output file */
   {
    output=argv[++i];
-   if (output==NULL || *output==0) usage(LUA_QL("-o") " needs argument");
+   if (output==NULL || *output==0 || (*output=='-' && output[1]!=0))
+    usage(LUA_QL("-o") " needs argument");
    if (IS("-")) output=NULL;
   }
   else if (IS("-p"))			/* parse only */
@@ -108,13 +108,30 @@ static int doargs(int argc, char* argv[])
  }
  if (version)
  {
-  printf("%s  %s\n",LUA_RELEASE,LUA_COPYRIGHT);
+  printf("%s\n",LUA_COPYRIGHT);
   if (version==argc-1) exit(EXIT_SUCCESS);
  }
  return i;
 }
 
-#define toproto(L,i) (clvalue(L->top+(i))->l.p)
+#define FUNCTION "(function()end)();"
+
+static const char* reader(lua_State *L, void *ud, size_t *size)
+{
+ UNUSED(L);
+ if ((*(int*)ud)--)
+ {
+  *size=sizeof(FUNCTION)-1;
+  return FUNCTION;
+ }
+ else
+ {
+  *size=0;
+  return NULL;
+ }
+}
+
+#define toproto(L,i) getproto(L->top+(i))
 
 static const Proto* combine(lua_State* L, int n)
 {
@@ -122,24 +139,16 @@ static const Proto* combine(lua_State* L, int n)
   return toproto(L,-1);
  else
  {
-  int i,pc;
-  Proto* f=luaF_newproto(L);
-  setptvalue2s(L,L->top,f); incr_top(L);
-  f->source=luaS_newliteral(L,"=(" PROGNAME ")");
-  f->maxstacksize=1;
-  pc=2*n+1;
-  f->code=luaM_newvector(L,pc,Instruction);
-  f->sizecode=pc;
-  f->p=luaM_newvector(L,n,Proto*);
-  f->sizep=n;
-  pc=0;
+  Proto* f;
+  int i=n;
+  if (lua_load(L,reader,&i,"=(" PROGNAME ")")!=LUA_OK) fatal(lua_tostring(L,-1));
+  f=toproto(L,-1);
   for (i=0; i<n; i++)
   {
    f->p[i]=toproto(L,i-n-1);
-   f->code[pc++]=CREATE_ABx(OP_CLOSURE,0,i);
-   f->code[pc++]=CREATE_ABC(OP_CALL,0,1,1);
+   if (f->p[i]->sizeupvalues>0) f->p[i]->upvalues[0].instack=0;
   }
-  f->code[pc++]=CREATE_ABC(OP_RETURN,0,1,0);
+  f->sizelineinfo=0;
   return f;
  }
 }
@@ -150,23 +159,17 @@ static int writer(lua_State* L, const void* p, size_t size, void* u)
  return (fwrite(p,size,1,(FILE*)u)!=1) && (size!=0);
 }
 
-struct Smain {
- int argc;
- char** argv;
-};
-
 static int pmain(lua_State* L)
 {
- struct Smain* s = (struct Smain*)lua_touserdata(L, 1);
- int argc=s->argc;
- char** argv=s->argv;
+ int argc=(int)lua_tointeger(L,1);
+ char** argv=(char**)lua_touserdata(L,2);
  const Proto* f;
  int i;
  if (!lua_checkstack(L,argc)) fatal("too many input files");
  for (i=0; i<argc; i++)
  {
   const char* filename=IS("-") ? NULL : argv[i];
-  if (luaL_loadfile(L,filename)!=0) fatal(lua_tostring(L,-1));
+  if (luaL_loadfile(L,filename)!=LUA_OK) fatal(lua_tostring(L,-1));
  }
  f=combine(L,argc);
  if (listing) luaU_print(f,listing>1);
@@ -186,15 +189,245 @@ static int pmain(lua_State* L)
 int main(int argc, char* argv[])
 {
  lua_State* L;
- struct Smain s;
  int i=doargs(argc,argv);
  argc-=i; argv+=i;
  if (argc<=0) usage("no input files given");
- L=lua_open();
- if (L==NULL) fatal("not enough memory for state");
- s.argc=argc;
- s.argv=argv;
- if (lua_cpcall(L,pmain,&s)!=0) fatal(lua_tostring(L,-1));
+ L=luaL_newstate();
+ if (L==NULL) fatal("cannot create state: not enough memory");
+ lua_pushcfunction(L,&pmain);
+ lua_pushinteger(L,argc);
+ lua_pushlightuserdata(L,argv);
+ if (lua_pcall(L,2,0,0)!=LUA_OK) fatal(lua_tostring(L,-1));
  lua_close(L);
  return EXIT_SUCCESS;
 }
+
+/*
+** $Id: print.c,v 1.67 2011/05/06 13:37:15 lhf Exp $
+** print bytecodes
+** See Copyright Notice in lua.h
+*/
+
+#include <ctype.h>
+#include <stdio.h>
+
+#define luac_c
+#define LUA_CORE
+
+#include "ldebug.h"
+#include "lobject.h"
+#include "lopcodes.h"
+
+#define Sizeof(x)	((int)sizeof(x))
+#define VOID(p)		((const void*)(p))
+
+static void PrintString(const TString* ts)
+{
+ const char* s=getstr(ts);
+ size_t i,n=ts->tsv.len;
+ printf("%c",'"');
+ for (i=0; i<n; i++)
+ {
+  int c=(int)(unsigned char)s[i];
+  switch (c)
+  {
+   case '"':  printf("\\\""); break;
+   case '\\': printf("\\\\"); break;
+   case '\a': printf("\\a"); break;
+   case '\b': printf("\\b"); break;
+   case '\f': printf("\\f"); break;
+   case '\n': printf("\\n"); break;
+   case '\r': printf("\\r"); break;
+   case '\t': printf("\\t"); break;
+   case '\v': printf("\\v"); break;
+   default:	if (isprint(c))
+   			printf("%c",c);
+		else
+			printf("\\%03d",c);
+  }
+ }
+ printf("%c",'"');
+}
+
+static void PrintConstant(const Proto* f, int i)
+{
+ const TValue* o=&f->k[i];
+ switch (ttype(o))
+ {
+  case LUA_TNIL:
+	printf("nil");
+	break;
+  case LUA_TBOOLEAN:
+	printf(bvalue(o) ? "true" : "false");
+	break;
+  case LUA_TNUMBER:
+	printf(LUA_NUMBER_FMT,nvalue(o));
+	break;
+  case LUA_TSTRING:
+	PrintString(rawtsvalue(o));
+	break;
+  default:				/* cannot happen */
+	printf("? type=%d",ttype(o));
+	break;
+ }
+}
+
+#define UPVALNAME(x) ((f->upvalues[x].name) ? getstr(f->upvalues[x].name) : "-")
+#define MYK(x)		(-1-(x))
+
+static void PrintCode(const Proto* f)
+{
+ const Instruction* code=f->code;
+ int pc,n=f->sizecode;
+ for (pc=0; pc<n; pc++)
+ {
+  Instruction i=code[pc];
+  OpCode o=GET_OPCODE(i);
+  int a=GETARG_A(i);
+  int b=GETARG_B(i);
+  int c=GETARG_C(i);
+  int ax=GETARG_Ax(i);
+  int bx=GETARG_Bx(i);
+  int sbx=GETARG_sBx(i);
+  int line=getfuncline(f,pc);
+  printf("\t%d\t",pc+1);
+  if (line>0) printf("[%d]\t",line); else printf("[-]\t");
+  printf("%-9s\t",luaP_opnames[o]);
+  switch (getOpMode(o))
+  {
+   case iABC:
+    printf("%d",a);
+    if (getBMode(o)!=OpArgN) printf(" %d",ISK(b) ? (MYK(INDEXK(b))) : b);
+    if (getCMode(o)!=OpArgN) printf(" %d",ISK(c) ? (MYK(INDEXK(c))) : c);
+    break;
+   case iABx:
+    printf("%d",a);
+    if (getBMode(o)==OpArgK) printf(" %d",MYK(bx));
+    if (getBMode(o)==OpArgU) printf(" %d",bx);
+    break;
+   case iAsBx:
+    printf("%d %d",a,sbx);
+    break;
+   case iAx:
+    printf("%d",MYK(ax));
+    break;
+  }
+  switch (o)
+  {
+   case OP_LOADK:
+    printf("\t; "); PrintConstant(f,bx);
+    break;
+   case OP_GETUPVAL:
+   case OP_SETUPVAL:
+    printf("\t; %s",UPVALNAME(b));
+    break;
+   case OP_GETTABUP:
+    printf("\t; %s",UPVALNAME(b));
+    if (ISK(c)) { printf(" "); PrintConstant(f,INDEXK(c)); }
+    break;
+   case OP_SETTABUP:
+    printf("\t; %s",UPVALNAME(a));
+    if (ISK(b)) { printf(" "); PrintConstant(f,INDEXK(b)); }
+    if (ISK(c)) { printf(" "); PrintConstant(f,INDEXK(c)); }
+    break;
+   case OP_GETTABLE:
+   case OP_SELF:
+    if (ISK(c)) { printf("\t; "); PrintConstant(f,INDEXK(c)); }
+    break;
+   case OP_SETTABLE:
+   case OP_ADD:
+   case OP_SUB:
+   case OP_MUL:
+   case OP_DIV:
+   case OP_POW:
+   case OP_EQ:
+   case OP_LT:
+   case OP_LE:
+    if (ISK(b) || ISK(c))
+    {
+     printf("\t; ");
+     if (ISK(b)) PrintConstant(f,INDEXK(b)); else printf("-");
+     printf(" ");
+     if (ISK(c)) PrintConstant(f,INDEXK(c)); else printf("-");
+    }
+    break;
+   case OP_JMP:
+   case OP_FORLOOP:
+   case OP_FORPREP:
+   case OP_TFORLOOP:
+    printf("\t; to %d",sbx+pc+2);
+    break;
+   case OP_CLOSURE:
+    printf("\t; %p",VOID(f->p[bx]));
+    break;
+   case OP_SETLIST:
+    if (c==0) printf("\t; %d",(int)code[++pc]); else printf("\t; %d",c);
+    break;
+   case OP_EXTRAARG:
+    printf("\t; "); PrintConstant(f,ax);
+    break;
+   default:
+    break;
+  }
+  printf("\n");
+ }
+}
+
+#define SS(x)	((x==1)?"":"s")
+#define S(x)	(int)(x),SS(x)
+
+static void PrintHeader(const Proto* f)
+{
+ const char* s=f->source ? getstr(f->source) : "=?";
+ if (*s=='@' || *s=='=')
+  s++;
+ else if (*s==LUA_SIGNATURE[0])
+  s="(bstring)";
+ else
+  s="(string)";
+ printf("\n%s <%s:%d,%d> (%d instruction%s at %p)\n",
+ 	(f->linedefined==0)?"main":"function",s,
+	f->linedefined,f->lastlinedefined,
+	S(f->sizecode),VOID(f));
+ printf("%d%s param%s, %d slot%s, %d upvalue%s, ",
+	(int)(f->numparams),f->is_vararg?"+":"",SS(f->numparams),
+	S(f->maxstacksize),S(f->sizeupvalues));
+ printf("%d local%s, %d constant%s, %d function%s\n",
+	S(f->sizelocvars),S(f->sizek),S(f->sizep));
+}
+
+static void PrintDebug(const Proto* f)
+{
+ int i,n;
+ n=f->sizek;
+ printf("constants (%d) for %p:\n",n,VOID(f));
+ for (i=0; i<n; i++)
+ {
+  printf("\t%d\t",i+1);
+  PrintConstant(f,i);
+  printf("\n");
+ }
+ n=f->sizelocvars;
+ printf("locals (%d) for %p:\n",n,VOID(f));
+ for (i=0; i<n; i++)
+ {
+  printf("\t%d\t%s\t%d\t%d\n",
+  i,getstr(f->locvars[i].varname),f->locvars[i].startpc+1,f->locvars[i].endpc+1);
+ }
+ n=f->sizeupvalues;
+ printf("upvalues (%d) for %p:\n",n,VOID(f));
+ for (i=0; i<n; i++)
+ {
+  printf("\t%d\t%s\t%d\t%d\n",
+  i,UPVALNAME(i),f->upvalues[i].instack,f->upvalues[i].idx);
+ }
+}
+
+static void PrintFunction(const Proto* f, int full)
+{
+ int i,n=f->sizep;
+ PrintHeader(f);
+ PrintCode(f);
+ if (full) PrintDebug(f);
+ for (i=0; i<n; i++) PrintFunction(f->p[i],full);
+}
diff --git a/src/luac.rc b/src/luac.rc
index 7caa98c..60eca7a 100644
--- a/src/luac.rc
+++ b/src/luac.rc
@@ -1 +1,28 @@
 0  ICON  "..\\etc\\lua.ico"

+

+1 VERSIONINFO

+ FILEVERSION 5,2,0,0

+ PRODUCTVERSION 5,2,0,0

+BEGIN

+    BLOCK "StringFileInfo"

+    BEGIN

+        BLOCK "040904b0"

+        BEGIN

+            VALUE "Comments", "www.lua.org\0"

+            VALUE "CompanyName", "Lua.org\0"

+            VALUE "FileDescription", "Lua Console Compiler\0"

+            VALUE "FileVersion", "5.2.0-beta\0"

+            VALUE "LegalCopyright", "Copyright © 1994-2011 Lua.org, PUC-Rio.\0"

+            VALUE "OriginalFilename", "luac.exe\0"

+            VALUE "ProductName", "Lua - The Programming Language\0"

+            VALUE "ProductVersion", "5.2.0-beta\0"

+            VALUE "PrivateBuild", "Built using LuaDist\0"

+        END

+    END

+END

+

+#ifdef MSVC8

+1 24 "lua_dll8.manifest"

+#elif MSVC9

+1 24 "lua_dll9.manifest"

+#endif

diff --git a/src/luaconf.h.in b/src/luaconf.h.in
index 7102028..e4916f0 100644
--- a/src/luaconf.h.in
+++ b/src/luaconf.h.in
@@ -1,5 +1,5 @@
 /*
-** $Id: luaconf.h,v 1.82.1.7 2008/02/11 16:25:08 roberto Exp $
+** $Id: luaconf.h,v 1.161 2011/07/08 20:07:11 roberto Exp $
 ** Configuration file for Lua
 ** See Copyright Notice in lua.h
 */
@@ -25,33 +25,25 @@
 ** non-ansi feature or library.
 */
 #cmakedefine LUA_ANSI
-
 #cmakedefine LUA_WIN
+
+#if defined(LUA_WIN)
+#undef LUA_ANSI
+#define LUA_DL_DLL
+#define LUA_USE_AFORMAT		/* assume 'printf' handles 'aA' specifiers */
+#endif
+
 #cmakedefine LUA_USE_POSIX
 #cmakedefine LUA_USE_DLOPEN		/* needs an extra library: -ldl */
 #cmakedefine LUA_USE_READLINE	/* needs some extra libraries */
-
+#cmakedefine LUA_USE_STRTODHEX	/* assume 'strtod' handles hexa formats */
+#cmakedefine LUA_USE_AFORMAT	/* assume 'printf' handles 'aA' specifiers */
+#cmakedefine LUA_USE_LONGLONG	/* assume support for long long */
 #cmakedefine LUA_USE_MKSTEMP
 #cmakedefine LUA_USE_ISATTY
 #cmakedefine LUA_USE_POPEN
 #cmakedefine LUA_USE_ULONGJMP
 
-//#if defined(LUA_USE_MACOSX)
-//#define LUA_USE_POSIX
-//#define LUA_DL_DYLD		/* does not need extra library */
-//#endif
-
-/*
-@@ LUA_PATH and LUA_CPATH are the names of the environment variables that
-@* Lua check to set its paths.
-@@ LUA_INIT is the name of the environment variable that Lua
-@* checks for initialization code.
-** CHANGE them if you want different names.
-*/
-#cmakedefine LUA_PATH "@LUA_PATH@"
-#cmakedefine LUA_CPATH "@LUA_CPATH@"
-#cmakedefine LUA_INIT "@LUA_INIT@"
-
 /*
 @@ LUA_PATH_DEFAULT is the default path that Lua uses to look for
 @* Lua libraries.
@@ -79,79 +71,72 @@
 #cmakedefine LUA_DIRSEP	"@LUA_DIRSEP@"
 
 /*
-@@ LUA_PATHSEP is the character that separates templates in a path.
-@@ LUA_PATH_MARK is the string that marks the substitution points in a
-@* template.
-@@ LUA_EXECDIR in a Windows path is replaced by the executable's
-@* directory.
-@@ LUA_IGMARK is a mark to ignore all before it when bulding the
-@* luaopen_ function name.
-** CHANGE them if for some reason your system cannot use those
-** characters. (E.g., if one of those characters is a common character
-** in file/directory names.) Probably you do not need to change them.
+@@ LUA_ENV is the name of the variable that holds the current
+@@ environment, used to access global names.
+** CHANGE it if you do not like this name.
 */
-#define LUA_PATHSEP	";"
-#define LUA_PATH_MARK	"?"
-#define LUA_EXECDIR	"!"
-#define LUA_IGMARK	"-"
-
-
-/*
-@@ LUA_INTEGER is the integral type used by lua_pushinteger/lua_tointeger.
-** CHANGE that if ptrdiff_t is not adequate on your machine. (On most
-** machines, ptrdiff_t gives a good choice between int or long.)
-*/
-#define LUA_INTEGER	ptrdiff_t
+#define LUA_ENV		"_ENV"
 
 
 /*
 @@ LUA_API is a mark for all core API functions.
-@@ LUALIB_API is a mark for all standard library functions.
+@@ LUALIB_API is a mark for all auxiliary library functions.
+@@ LUAMOD_API is a mark for all standard library opening functions.
 ** CHANGE them if you need to define those functions in some special way.
 ** For instance, if you want to create one Windows DLL with the core and
 ** the libraries, you may want to use the following definition (define
 ** LUA_BUILD_AS_DLL to get it).
 */
-#if defined(LUA_BUILD_AS_DLL)
+#if defined(LUA_BUILD_AS_DLL)	/* { */
 
-#if defined(LUA_CORE) || defined(LUA_LIB)
+#if defined(LUA_CORE) || defined(LUA_LIB)	/* { */
 #define LUA_API __declspec(dllexport)
-#else
+#else						/* }{ */
 #define LUA_API __declspec(dllimport)
-#endif
+#endif						/* } */
 
-#else
+#else				/* }{ */
 
 #define LUA_API		extern
 
-#endif
+#endif				/* } */
+
 
 /* more often than not the libs go together with the core */
 #define LUALIB_API	LUA_API
+#define LUAMOD_API	LUALIB_API
 
 
 /*
 @@ LUAI_FUNC is a mark for all extern functions that are not to be
 @* exported to outside modules.
-@@ LUAI_DATA is a mark for all extern (const) variables that are not to
-@* be exported to outside modules.
+@@ LUAI_DDEF and LUAI_DDEC are marks for all extern (const) variables
+@* that are not to be exported to outside modules (LUAI_DDEF for
+@* definitions and LUAI_DDEC for declarations).
 ** CHANGE them if you need to mark them in some special way. Elf/gcc
 ** (versions 3.2 and later) mark them as "hidden" to optimize access
-** when Lua is compiled as a shared library.
+** when Lua is compiled as a shared library. Not all elf targets support
+** this attribute. Unfortunately, gcc does not offer a way to check
+** whether the target offers that support, and those without support
+** give a warning about it. To avoid these warnings, change to the
+** default definition.
 */
-#if defined(luaall_c)
+#if defined(luaall_c)		/* { */
 #define LUAI_FUNC	static
-#define LUAI_DATA	/* empty */
+#define LUAI_DDEC	static
+#define LUAI_DDEF	static
 
 #elif defined(__GNUC__) && ((__GNUC__*100 + __GNUC_MINOR__) >= 302) && \
       defined(__ELF__)
 #define LUAI_FUNC	__attribute__((visibility("hidden"))) extern
-#define LUAI_DATA	LUAI_FUNC
+#define LUAI_DDEC	LUAI_FUNC
+#define LUAI_DDEF	/* empty */
 
-#else
+#else				/* }{ */
 #define LUAI_FUNC	extern
-#define LUAI_DATA	extern
-#endif
+#define LUAI_DDEC	extern
+#define LUAI_DDEF	/* empty */
+#endif				/* } */
 
 
 
@@ -168,179 +153,102 @@
 @* of a function in debug information.
 ** CHANGE it if you want a different size.
 */
-#cmakedefine LUA_IDSIZE	@LUA_IDSIZE@
+#define LUA_IDSIZE	60
 
 
 /*
-** {==================================================================
-** Stand-alone configuration
-** ===================================================================
+@@ luai_writestring/luai_writeline define how 'print' prints its results.
 */
-
-#if defined(lua_c) || defined(luaall_c)
+#include <stdio.h>
+#define luai_writestring(s,l)	fwrite((s), sizeof(char), (l), stdout)
+#define luai_writeline()	(luai_writestring("\n", 1), fflush(stdout))
 
 /*
-@@ lua_stdin_is_tty detects whether the standard input is a 'tty' (that
-@* is, whether we're running lua interactively).
-** CHANGE it if you have a better definition for non-POSIX/non-Windows
-** systems.
+@@ luai_writestringerror defines how to print error messages.
+** (A format string with one argument is enough for Lua...)
 */
-#if defined(LUA_USE_ISATTY)
-#include <unistd.h>
-#define lua_stdin_is_tty()	isatty(0)
-#elif defined(LUA_WIN)
-#include <io.h>
-#include <stdio.h>
-#define lua_stdin_is_tty()	_isatty(_fileno(stdin))
-#else
-#define lua_stdin_is_tty()	1  /* assume stdin is a tty */
-#endif
+#define luai_writestringerror(s,p) \
+	(fprintf(stderr, (s), (p)), fflush(stderr))
+
 
 
-/*
-@@ LUA_PROMPT is the default prompt used by stand-alone Lua.
-@@ LUA_PROMPT2 is the default continuation prompt used by stand-alone Lua.
-** CHANGE them if you want different prompts. (You can also change the
-** prompts dynamically, assigning to globals _PROMPT/_PROMPT2.)
-*/
-#cmakedefine LUA_PROMPT		"@LUA_PROMPT@"
-#cmakedefine LUA_PROMPT2	"@LUA_PROMPT2@"
 
 
 /*
-@@ LUA_PROGNAME is the default name for the stand-alone Lua program.
-** CHANGE it if your stand-alone interpreter has a different name and
-** your system is not able to detect that name automatically.
+** {==================================================================
+** Compatibility with previous versions
+** ===================================================================
 */
-#define LUA_PROGNAME		"lua"
-
 
 /*
-@@ LUA_MAXINPUT is the maximum length for an input line in the
-@* stand-alone interpreter.
-** CHANGE it if you need longer lines.
+@@ LUA_COMPAT_ALL controls all compatibility options.
+** You can define it to get all options, or change specific options
+** to fit your specific needs.
 */
-#cmakedefine LUA_MAXINPUT	@LUA_MAXINPUT@
-
+#cmakedefine LUA_COMPAT_ALL
+#if defined(LUA_COMPAT_ALL)	/* { */
 
 /*
-@@ lua_readline defines how to show a prompt and then read a line from
-@* the standard input.
-@@ lua_saveline defines how to "save" a read line in a "history".
-@@ lua_freeline defines how to free a line read by lua_readline.
-** CHANGE them if you want to improve this functionality (e.g., by using
-** GNU readline and history facilities).
+@@ LUA_COMPAT_UNPACK controls the presence of global 'unpack'.
+** You can replace it with 'table.unpack'.
 */
-#if defined(LUA_USE_READLINE)
-#include <stdio.h>
-#include <readline/readline.h>
-#include <readline/history.h>
-#define lua_readline(L,b,p)	((void)L, ((b)=readline(p)) != NULL)
-#define lua_saveline(L,idx) \
-	if (lua_strlen(L,idx) > 0)  /* non-empty line? */ \
-	  add_history(lua_tostring(L, idx));  /* add it to history */
-#define lua_freeline(L,b)	((void)L, free(b))
-#else
-#define lua_readline(L,b,p)	\
-	((void)L, fputs(p, stdout), fflush(stdout),  /* show prompt */ \
-	fgets(b, LUA_MAXINPUT, stdin) != NULL)  /* get line */
-#define lua_saveline(L,idx)	{ (void)L; (void)idx; }
-#define lua_freeline(L,b)	{ (void)L; (void)b; }
-#endif
-
-#endif
-
-/* }================================================================== */
-
+#define LUA_COMPAT_UNPACK
 
 /*
-@@ LUAI_GCPAUSE defines the default pause between garbage-collector cycles
-@* as a percentage.
-** CHANGE it if you want the GC to run faster or slower (higher values
-** mean larger pauses which mean slower collection.) You can also change
-** this value dynamically.
+@@ LUA_COMPAT_LOADERS controls the presence of table 'package.loaders'.
+** You can replace it with 'package.searchers'.
 */
-#define LUAI_GCPAUSE	200  /* 200% (wait memory to double before next GC) */
-
+#define LUA_COMPAT_LOADERS
 
 /*
-@@ LUAI_GCMUL defines the default speed of garbage collection relative to
-@* memory allocation as a percentage.
-** CHANGE it if you want to change the granularity of the garbage
-** collection. (Higher values mean coarser collections. 0 represents
-** infinity, where each step performs a full collection.) You can also
-** change this value dynamically.
+@@ macro 'lua_cpcall' emulates deprecated function lua_cpcall.
+** You can call your C function directly (with light C functions).
 */
-#define LUAI_GCMUL	200 /* GC runs 'twice the speed' of memory allocation */
-
+#define lua_cpcall(L,f,u)  \
+	(lua_pushcfunction(L, (f)), \
+	 lua_pushlightuserdata(L,(u)), \
+	 lua_pcall(L,1,0,0))
 
 
 /*
-@@ LUA_COMPAT_GETN controls compatibility with old getn behavior.
-** CHANGE it (define it) if you want exact compatibility with the
-** behavior of setn/getn in Lua 5.0.
+@@ LUA_COMPAT_LOG10 defines the function 'log10' in the math library.
+** You can rewrite 'log10(x)' as 'log(x, 10)'.
 */
-#undef LUA_COMPAT_GETN
+#define LUA_COMPAT_LOG10
 
 /*
-@@ LUA_COMPAT_LOADLIB controls compatibility about global loadlib.
-** CHANGE it to undefined as soon as you do not need a global 'loadlib'
-** function (the function is still available as 'package.loadlib').
+@@ LUA_COMPAT_LOADSTRING defines the function 'loadstring' in the base
+** library. You can rewrite 'loadstring(s)' as 'load(s)'.
 */
-#undef LUA_COMPAT_LOADLIB
+#define LUA_COMPAT_LOADSTRING
 
 /*
-@@ LUA_COMPAT_VARARG controls compatibility with old vararg feature.
-** CHANGE it to undefined as soon as your programs use only '...' to
-** access vararg parameters (instead of the old 'arg' table).
+@@ LUA_COMPAT_MAXN defines the function 'maxn' in the table library.
 */
-#define LUA_COMPAT_VARARG
+#define LUA_COMPAT_MAXN
 
 /*
-@@ LUA_COMPAT_MOD controls compatibility with old math.mod function.
-** CHANGE it to undefined as soon as your programs use 'math.fmod' or
-** the new '%' operator instead of 'math.mod'.
+@@ The following macros supply trivial compatibility for some
+** changes in the API. The macros themselves document how to
+** change your code to avoid using them.
 */
-#define LUA_COMPAT_MOD
+#define lua_strlen(L,i)		lua_rawlen(L, (i))
 
-/*
-@@ LUA_COMPAT_LSTR controls compatibility with old long string nesting
-@* facility.
-** CHANGE it to 2 if you want the old behaviour, or undefine it to turn
-** off the advisory error when nesting [[...]].
-*/
-#define LUA_COMPAT_LSTR		1
+#define lua_objlen(L,i)		lua_rawlen(L, (i))
 
-/*
-@@ LUA_COMPAT_GFIND controls compatibility with old 'string.gfind' name.
-** CHANGE it to undefined as soon as you rename 'string.gfind' to
-** 'string.gmatch'.
-*/
-#define LUA_COMPAT_GFIND
+#define lua_equal(L,idx1,idx2)		lua_compare(L,(idx1),(idx2),LUA_OPEQ)
+#define lua_lessthan(L,idx1,idx2)	lua_compare(L,(idx1),(idx2),LUA_OPLT)
 
 /*
-@@ LUA_COMPAT_OPENLIB controls compatibility with old 'luaL_openlib'
-@* behavior.
-** CHANGE it to undefined as soon as you replace to 'luaL_register'
-** your uses of 'luaL_openlib'
+@@ LUA_COMPAT_MODULE controls compatibility with previous
+** module functions 'module' (Lua) and 'luaL_register' (C).
 */
-#define LUA_COMPAT_OPENLIB
+#define LUA_COMPAT_MODULE
 
+#endif				/* } */
 
+/* }================================================================== */
 
-/*
-@@ luai_apicheck is the assert macro used by the Lua-C API.
-** CHANGE luai_apicheck if you want Lua to perform some checks in the
-** parameters it gets from API calls. This may slow down the interpreter
-** a bit, but may be quite useful when debugging C code that interfaces
-** with Lua. A useful redefinition is to use assert.h.
-*/
-#if defined(LUA_USE_APICHECK)
-#include <assert.h>
-#define luai_apicheck(L,o)	{ (void)L; assert(o); }
-#else
-#define luai_apicheck(L,o)	{ (void)L; }
-#endif
 
 
 /*
@@ -349,107 +257,62 @@
 ** your machine. Probably you do not need to change this.
 */
 /* avoid overflows in comparison */
-#if INT_MAX-20 < 32760
+#if INT_MAX-20 < 32760		/* { */
 #define LUAI_BITSINT	16
-#elif INT_MAX > 2147483640L
+#elif INT_MAX > 2147483640L	/* }{ */
 /* int has at least 32 bits */
 #define LUAI_BITSINT	32
-#else
+#else				/* }{ */
 #error "you must define LUA_BITSINT with number of bits in an integer"
-#endif
+#endif				/* } */
 
 
 /*
-@@ LUAI_UINT32 is an unsigned integer with at least 32 bits.
-@@ LUAI_INT32 is an signed integer with at least 32 bits.
+@@ LUA_INT32 is an signed integer with exactly 32 bits.
 @@ LUAI_UMEM is an unsigned integer big enough to count the total
 @* memory used by Lua.
 @@ LUAI_MEM is a signed integer big enough to count the total memory
 @* used by Lua.
 ** CHANGE here if for some weird reason the default definitions are not
-** good enough for your machine. (The definitions in the 'else'
-** part always works, but may waste space on machines with 64-bit
-** longs.) Probably you do not need to change this.
+** good enough for your machine. Probably you do not need to change
+** this.
 */
-#if LUAI_BITSINT >= 32
-#define LUAI_UINT32	unsigned int
-#define LUAI_INT32	int
-#define LUAI_MAXINT32	INT_MAX
+#if LUAI_BITSINT >= 32		/* { */
+#define LUA_INT32	int
 #define LUAI_UMEM	size_t
 #define LUAI_MEM	ptrdiff_t
-#else
+#else				/* }{ */
 /* 16-bit ints */
-#define LUAI_UINT32	unsigned long
-#define LUAI_INT32	long
-#define LUAI_MAXINT32	LONG_MAX
+#define LUA_INT32	long
 #define LUAI_UMEM	unsigned long
 #define LUAI_MEM	long
-#endif
-
-
-/*
-@@ LUAI_MAXCALLS limits the number of nested calls.
-** CHANGE it if you need really deep recursive calls. This limit is
-** arbitrary; its only purpose is to stop infinite recursion before
-** exhausting memory.
-*/
-#define LUAI_MAXCALLS	20000
-
-
-/*
-@@ LUAI_MAXCSTACK limits the number of Lua stack slots that a C function
-@* can use.
-** CHANGE it if you need lots of (Lua) stack space for your C
-** functions. This limit is arbitrary; its only purpose is to stop C
-** functions to consume unlimited stack space. (must be smaller than
-** -LUA_REGISTRYINDEX)
-*/
-#define LUAI_MAXCSTACK	8000
-
-
-
-/*
-** {==================================================================
-** CHANGE (to smaller values) the following definitions if your system
-** has a small C stack. (Or you may want to change them to larger
-** values if your system has a large C stack and these limits are
-** too rigid for you.) Some of these constants control the size of
-** stack-allocated arrays used by the compiler or the interpreter, while
-** others limit the maximum number of recursive calls that the compiler
-** or the interpreter can perform. Values too large may cause a C stack
-** overflow for some forms of deep constructs.
-** ===================================================================
-*/
+#endif				/* } */
 
 
 /*
-@@ LUAI_MAXCCALLS is the maximum depth for nested C calls (short) and
-@* syntactical nested non-terminals in a program.
+@@ LUAI_MAXSTACK limits the size of the Lua stack.
+** CHANGE it if you need a different limit. This limit is arbitrary;
+** its only purpose is to stop Lua to consume unlimited stack
+** space (and to reserve some numbers for pseudo-indices).
 */
-#define LUAI_MAXCCALLS		200
+#if LUAI_BITSINT >= 32
+#define LUAI_MAXSTACK		1000000
+#else
+#define LUAI_MAXSTACK		15000
+#endif
 
+/* reserve some space for error handling */
+#define LUAI_FIRSTPSEUDOIDX	(-LUAI_MAXSTACK - 1000)
 
-/*
-@@ LUAI_MAXVARS is the maximum number of local variables per function
-@* (must be smaller than 250).
-*/
-#define LUAI_MAXVARS		200
 
 
-/*
-@@ LUAI_MAXUPVALUES is the maximum number of upvalues per function
-@* (must be smaller than 250).
-*/
-#define LUAI_MAXUPVALUES	60
-
 
 /*
 @@ LUAL_BUFFERSIZE is the buffer size used by the lauxlib buffer system.
+** CHANGE it if it uses too much C-stack space.
 */
 #define LUAL_BUFFERSIZE		BUFSIZ
 
-/* }================================================================== */
-
 
 
 
@@ -477,237 +340,127 @@
 @@ LUA_NUMBER_FMT is the format for writing numbers.
 @@ lua_number2str converts a number to a string.
 @@ LUAI_MAXNUMBER2STR is maximum size of previous conversion.
-@@ lua_str2number converts a string to a number.
 */
 #define LUA_NUMBER_SCAN		"%lf"
 #define LUA_NUMBER_FMT		"%.14g"
 #define lua_number2str(s,n)	sprintf((s), LUA_NUMBER_FMT, (n))
 #define LUAI_MAXNUMBER2STR	32 /* 16 digits, sign, point, and \0 */
-#define lua_str2number(s,p)	strtod((s), (p))
 
 
 /*
-@@ The luai_num* macros define the primitive operations over numbers.
+@@ lua_str2number converts a decimal numeric string to a number.
+@@ lua_strx2number converts an hexadecimal numeric string to a number.
+** In C99, 'strtod' do both conversions. C89, however, has no function
+** to convert floating hexadecimal strings to numbers. For these
+** systems, you can leave 'lua_strx2number' undefined and Lua will
+** provide its own implementation.
 */
-#if defined(LUA_CORE)
-#include <math.h>
-#define luai_numadd(a,b)	((a)+(b))
-#define luai_numsub(a,b)	((a)-(b))
-#define luai_nummul(a,b)	((a)*(b))
-#define luai_numdiv(a,b)	((a)/(b))
-#define luai_nummod(a,b)	((a) - floor((a)/(b))*(b))
-#define luai_numpow(a,b)	(pow(a,b))
-#define luai_numunm(a)		(-(a))
-#define luai_numeq(a,b)		((a)==(b))
-#define luai_numlt(a,b)		((a)<(b))
-#define luai_numle(a,b)		((a)<=(b))
-#define luai_numisnan(a)	(!luai_numeq((a), (a)))
+#define lua_str2number(s,p)	strtod((s), (p))
+
+#if defined(LUA_USE_STRTODHEX)
+#define lua_strx2number(s,p)	strtod((s), (p))
 #endif
 
 
 /*
-@@ lua_number2int is a macro to convert lua_Number to int.
-@@ lua_number2integer is a macro to convert lua_Number to lua_Integer.
-** CHANGE them if you know a faster way to convert a lua_Number to
-** int (with any rounding method and without throwing errors) in your
-** system. In Pentium machines, a naive typecast from double to int
-** in C is extremely slow, so any alternative is worth trying.
+@@ The luai_num* macros define the primitive operations over numbers.
 */
 
-/* On a Pentium, resort to a trick */
-#if defined(LUA_NUMBER_DOUBLE) && !defined(LUA_ANSI) && !defined(__SSE2__) && \
-    (defined(__i386) || defined (_M_IX86) || defined(__i386__))
-
-/* On a Microsoft compiler, use assembler */
-#if defined(_MSC_VER)
-
-#define lua_number2int(i,d)   __asm fld d   __asm fistp i
-#define lua_number2integer(i,n)		lua_number2int(i, n)
-
-/* the next trick should work on any Pentium, but sometimes clashes
-   with a DirectX idiosyncrasy */
-#else
-
-union luai_Cast { double l_d; long l_l; };
-#define lua_number2int(i,d) \
-  { volatile union luai_Cast u; u.l_d = (d) + 6755399441055744.0; (i) = u.l_l; }
-#define lua_number2integer(i,n)		lua_number2int(i, n)
-
+/* the following operations need the math library */
+#if defined(lobject_c) || defined(lvm_c) || defined(luaall_c)
+#include <math.h>
+#define luai_nummod(L,a,b)	((a) - floor((a)/(b))*(b))
+#define luai_numpow(L,a,b)	(pow(a,b))
 #endif
 
-
-/* this option always works, but may be slow */
-#else
-#define lua_number2int(i,d)	((i)=(int)(d))
-#define lua_number2integer(i,d)	((i)=(lua_Integer)(d))
-
+/* these are quite standard operations */
+#if defined(LUA_CORE)
+#define luai_numadd(L,a,b)	((a)+(b))
+#define luai_numsub(L,a,b)	((a)-(b))
+#define luai_nummul(L,a,b)	((a)*(b))
+#define luai_numdiv(L,a,b)	((a)/(b))
+#define luai_numunm(L,a)	(-(a))
+#define luai_numeq(a,b)		((a)==(b))
+#define luai_numlt(L,a,b)	((a)<(b))
+#define luai_numle(L,a,b)	((a)<=(b))
+#define luai_numisnan(L,a)	(!luai_numeq((a), (a)))
 #endif
 
-/* }================================================================== */
 
 
 /*
-@@ LUAI_USER_ALIGNMENT_T is a type that requires maximum alignment.
-** CHANGE it if your system requires alignments larger than double. (For
-** instance, if your system supports long doubles and they must be
-** aligned in 16-byte boundaries, then you should add long double in the
-** union.) Probably you do not need to change this.
+@@ LUA_INTEGER is the integral type used by lua_pushinteger/lua_tointeger.
+** CHANGE that if ptrdiff_t is not adequate on your machine. (On most
+** machines, ptrdiff_t gives a good choice between int or long.)
 */
-#define LUAI_USER_ALIGNMENT_T	union { double u; void *s; long l; }
-
+#define LUA_INTEGER	ptrdiff_t
 
 /*
-@@ LUAI_THROW/LUAI_TRY define how Lua does exception handling.
-** CHANGE them if you prefer to use longjmp/setjmp even with C++
-** or if want/don't to use _longjmp/_setjmp instead of regular
-** longjmp/setjmp. By default, Lua handles errors with exceptions when
-** compiling as C++ code, with _longjmp/_setjmp when asked to use them,
-** and with longjmp/setjmp otherwise.
+@@ LUA_UNSIGNED is the integral type used by lua_pushunsigned/lua_tounsigned.
+** It must have at least 32 bits.
 */
-#if defined(__cplusplus)
-/* C++ exceptions */
-#define LUAI_THROW(L,c)	throw(c)
-#define LUAI_TRY(L,c,a)	try { a } catch(...) \
-	{ if ((c)->status == 0) (c)->status = -1; }
-#define luai_jmpbuf	int  /* dummy variable */
-
-#elif defined(LUA_USE_ULONGJMP)
-/* in Unix, try _longjmp/_setjmp (more efficient) */
-#define LUAI_THROW(L,c)	_longjmp((c)->b, 1)
-#define LUAI_TRY(L,c,a)	if (_setjmp((c)->b) == 0) { a }
-#define luai_jmpbuf	jmp_buf
-
-#else
-/* default handling with long jumps */
-#define LUAI_THROW(L,c)	longjmp((c)->b, 1)
-#define LUAI_TRY(L,c,a)	if (setjmp((c)->b) == 0) { a }
-#define luai_jmpbuf	jmp_buf
+#define LUA_UNSIGNED	unsigned LUA_INT32
 
-#endif
 
+#if defined(LUA_CORE)		/* { */
 
-/*
-@@ LUA_MAXCAPTURES is the maximum number of captures that a pattern
-@* can do during pattern-matching.
-** CHANGE it if you need more captures. This limit is arbitrary.
-*/
-#define LUA_MAXCAPTURES		32
+#if defined(LUA_NUMBER_DOUBLE) && !defined(LUA_ANSI)	/* { */
 
+/* On a Microsoft compiler on a Pentium, use assembler to avoid clashes
+   with a DirectX idiosyncrasy */
+#if defined(_MSC_VER) && defined(M_IX86)		/* { */
 
-/*
-@@ lua_tmpnam is the function that the OS library uses to create a
-@* temporary name.
-@@ LUA_TMPNAMBUFSIZE is the maximum size of a name created by lua_tmpnam.
-** CHANGE them if you have an alternative to tmpnam (which is considered
-** insecure) or if you want the original tmpnam anyway.  By default, Lua
-** uses tmpnam except when POSIX is available, where it uses mkstemp.
-*/
-#if defined(loslib_c) || defined(luaall_c)
-
-#if defined(LUA_USE_MKSTEMP)
-#include <unistd.h>
-#define LUA_TMPNAMBUFSIZE	32
-#define lua_tmpnam(b,e)	{ \
-	strcpy(b, "/tmp/lua_XXXXXX"); \
-	e = mkstemp(b); \
-	if (e != -1) close(e); \
-	e = (e == -1); }
+#define MS_ASMTRICK
 
-#else
-#define LUA_TMPNAMBUFSIZE	L_tmpnam
-#define lua_tmpnam(b,e)		{ e = (tmpnam(b) == NULL); }
-#endif
-
-#endif
+#else				/* }{ */
+/* the next definition uses a trick that should work on any machine
+   using IEEE754 with a 32-bit integer type */
 
+#define LUA_IEEE754TRICK
 
 /*
-@@ lua_popen spawns a new process connected to the current one through
-@* the file streams.
-** CHANGE it if you have a way to implement it in your system.
+@@ LUA_IEEEENDIAN is the endianness of doubles in your machine
+** (0 for little endian, 1 for big endian); if not defined, Lua will
+** check it dynamically.
 */
-#if defined(LUA_USE_POPEN)
-
-#define lua_popen(L,c,m)	((void)L, fflush(NULL), popen(c,m))
-#define lua_pclose(L,file)	((void)L, (pclose(file) != -1))
-
-#elif defined(LUA_WIN)
-
-#define lua_popen(L,c,m)	((void)L, _popen(c,m))
-#define lua_pclose(L,file)	((void)L, (_pclose(file) != -1))
-
-#else
-
-#define lua_popen(L,c,m)	((void)((void)c, m),  \
-		luaL_error(L, LUA_QL("popen") " not supported"), (FILE*)0)
-#define lua_pclose(L,file)		((void)((void)L, file), 0)
-
+/* check for known architectures */
+#if defined(__i386__) || defined(__i386) || defined(__X86__) || \
+    defined (__x86_64)
+#define LUA_IEEEENDIAN	0
+#elif defined(__POWERPC__) || defined(__ppc__)
+#define LUA_IEEEENDIAN	1
 #endif
 
-/*
-@@ LUA_DL_* define which dynamic-library system Lua should use.
-** CHANGE here if Lua has problems choosing the appropriate
-** dynamic-library system for your platform (either Windows' DLL, Mac's
-** dyld, or Unix's dlopen). If your system is some kind of Unix, there
-** is a good chance that it has dlopen, so LUA_DL_DLOPEN will work for
-** it.  To use dlopen you also need to adapt the src/Makefile (probably
-** adding -ldl to the linker options), so Lua does not select it
-** automatically.  (When you change the makefile to add -ldl, you must
-** also add -DLUA_USE_DLOPEN.)
-** If you do not want any kind of dynamic library, undefine all these
-** options.
-** By default, _WIN32 gets LUA_DL_DLL and MAC OS X gets LUA_DL_DYLD.
-*/
-#if defined(LUA_USE_DLOPEN)
-#define LUA_DL_DLOPEN
-#endif
+#endif				/* } */
 
-#if defined(LUA_WIN)
-#define LUA_DL_DLL
-#endif
+#endif			/* } */
 
+#endif			/* } */
 
-/*
-@@ LUAI_EXTRASPACE allows you to add user-specific data in a lua_State
-@* (the data goes just *before* the lua_State pointer).
-** CHANGE (define) this if you really need that. This value must be
-** a multiple of the maximum alignment required for your machine.
-*/
-#define LUAI_EXTRASPACE		0
-
-
-/*
-@@ luai_userstate* allow user-specific actions on threads.
-** CHANGE them if you defined LUAI_EXTRASPACE and need to do something
-** extra when a thread is created/deleted/resumed/yielded.
-*/
-#define luai_userstateopen(L)		((void)L)
-#define luai_userstateclose(L)		((void)L)
-#define luai_userstatethread(L,L1)	((void)L)
-#define luai_userstatefree(L)		((void)L)
-#define luai_userstateresume(L,n)	((void)L)
-#define luai_userstateyield(L,n)	((void)L)
+/* }================================================================== */
 
 
 /*
-@@ LUA_INTFRMLEN is the length modifier for integer conversions
-@* in 'string.format'.
-@@ LUA_INTFRM_T is the integer type correspoding to the previous length
-@* modifier.
-** CHANGE them if your system supports long long or does not support long.
+@@ LUA_NANTRICKLE/LUA_NANTRICKBE controls the use of a trick to pack all
+** types into a single double value, using NaN values to represent
+** non-number values. The trick only works on 32-bit machines (ints and
+** pointers are 32-bit values) with numbers represented as IEEE 754-2008
+** doubles with conventional endianess (12345678 or 87654321), in CPUs
+** that do not produce signaling NaN values (all NaNs are quiet).
 */
+#if defined(LUA_CORE) && \
+    defined(LUA_NUMBER_DOUBLE) && !defined(LUA_ANSI)	/* { */
 
-#if defined(LUA_USELONGLONG)
+/* little-endian architectures that satisfy those conditions */
+#if defined(__i386__) || defined(__i386) || defined(__X86__) || \
+    defined(_M_IX86)
 
-#define LUA_INTFRMLEN		"ll"
-#define LUA_INTFRM_T		long long
+#define LUA_NANTRICKLE
 
-#else
+#endif
 
-#define LUA_INTFRMLEN		"l"
-#define LUA_INTFRM_T		long
+#endif							/* } */
 
-#endif
 
 
 
diff --git a/src/luaconf.h.orig b/src/luaconf.h.orig
index e2cb261..1135e50 100644..100755
--- a/src/luaconf.h.orig
+++ b/src/luaconf.h.orig
@@ -1,5 +1,5 @@
 /*
-** $Id: luaconf.h,v 1.82.1.7 2008/02/11 16:25:08 roberto Exp $
+** $Id: luaconf.h,v 1.161 2011/07/08 20:07:11 roberto Exp $
 ** Configuration file for Lua
 ** See Copyright Notice in lua.h
 */
@@ -24,7 +24,7 @@
 ** CHANGE it (define it) if you want Lua to avoid the use of any
 ** non-ansi feature or library.
 */
-#if defined(__STRICT_ANSI__)
+#if !defined(LUA_ANSI) && defined(__STRICT_ANSI__)
 #define LUA_ANSI
 #endif
 
@@ -33,21 +33,35 @@
 #define LUA_WIN
 #endif
 
+#if defined(LUA_WIN)
+#define LUA_DL_DLL
+#define LUA_USE_AFORMAT		/* assume 'printf' handles 'aA' specifiers */
+#endif
+
+
+
 #if defined(LUA_USE_LINUX)
 #define LUA_USE_POSIX
 #define LUA_USE_DLOPEN		/* needs an extra library: -ldl */
 #define LUA_USE_READLINE	/* needs some extra libraries */
+#define LUA_USE_STRTODHEX	/* assume 'strtod' handles hexa formats */
+#define LUA_USE_AFORMAT		/* assume 'printf' handles 'aA' specifiers */
+#define LUA_USE_LONGLONG	/* assume support for long long */
 #endif
 
 #if defined(LUA_USE_MACOSX)
 #define LUA_USE_POSIX
-#define LUA_DL_DYLD		/* does not need extra library */
+#define LUA_USE_DLOPEN		/* does not need -ldl */
+#define LUA_USE_READLINE	/* needs an extra library: -lreadline */
+#define LUA_USE_STRTODHEX	/* assume 'strtod' handles hexa formats */
+#define LUA_USE_AFORMAT		/* assume 'printf' handles 'aA' specifiers */
+#define LUA_USE_LONGLONG	/* assume support for long long */
 #endif
 
 
 
 /*
-@@ LUA_USE_POSIX includes all functionallity listed as X/Open System
+@@ LUA_USE_POSIX includes all functionality listed as X/Open System
 @* Interfaces Extension (XSI).
 ** CHANGE it (define it) if your system is XSI compatible.
 */
@@ -59,17 +73,6 @@
 #endif
 
 
-/*
-@@ LUA_PATH and LUA_CPATH are the names of the environment variables that
-@* Lua check to set its paths.
-@@ LUA_INIT is the name of the environment variable that Lua
-@* checks for initialization code.
-** CHANGE them if you want different names.
-*/
-#define LUA_PATH        "LUA_PATH"
-#define LUA_CPATH       "LUA_CPATH"
-#define LUA_INIT	"LUA_INIT"
-
 
 /*
 @@ LUA_PATH_DEFAULT is the default path that Lua uses to look for
@@ -80,7 +83,7 @@
 ** hierarchy or if you want to install your libraries in
 ** non-conventional directories.
 */
-#if defined(_WIN32)
+#if defined(_WIN32)	/* { */
 /*
 ** In Windows, any exclamation mark ('!') in the path is replaced by the
 ** path of the directory of the executable file of the current process.
@@ -88,21 +91,23 @@
 #define LUA_LDIR	"!\\lua\\"
 #define LUA_CDIR	"!\\"
 #define LUA_PATH_DEFAULT  \
-		".\\?.lua;"  LUA_LDIR"?.lua;"  LUA_LDIR"?\\init.lua;" \
-		             LUA_CDIR"?.lua;"  LUA_CDIR"?\\init.lua"
+		LUA_LDIR"?.lua;"  LUA_LDIR"?\\init.lua;" \
+		LUA_CDIR"?.lua;"  LUA_CDIR"?\\init.lua;" ".\\?.lua"
 #define LUA_CPATH_DEFAULT \
-	".\\?.dll;"  LUA_CDIR"?.dll;" LUA_CDIR"loadall.dll"
+		LUA_CDIR"?.dll;" LUA_CDIR"loadall.dll;" ".\\?.dll"
 
-#else
+#else			/* }{ */
+
+#define LUA_VDIR	LUA_VERSION_MAJOR "." LUA_VERSION_MINOR "/"
 #define LUA_ROOT	"/usr/local/"
-#define LUA_LDIR	LUA_ROOT "share/lua/5.1/"
-#define LUA_CDIR	LUA_ROOT "lib/lua/5.1/"
+#define LUA_LDIR	LUA_ROOT "share/lua/" LUA_VDIR
+#define LUA_CDIR	LUA_ROOT "lib/lua/" LUA_VDIR
 #define LUA_PATH_DEFAULT  \
-		"./?.lua;"  LUA_LDIR"?.lua;"  LUA_LDIR"?/init.lua;" \
-		            LUA_CDIR"?.lua;"  LUA_CDIR"?/init.lua"
+		LUA_LDIR"?.lua;"  LUA_LDIR"?/init.lua;" \
+		LUA_CDIR"?.lua;"  LUA_CDIR"?/init.lua;" "./?.lua"
 #define LUA_CPATH_DEFAULT \
-	"./?.so;"  LUA_CDIR"?.so;" LUA_CDIR"loadall.so"
-#endif
+		LUA_CDIR"?.so;" LUA_CDIR"loadall.so;" "./?.so"
+#endif			/* } */
 
 
 /*
@@ -118,79 +123,72 @@
 
 
 /*
-@@ LUA_PATHSEP is the character that separates templates in a path.
-@@ LUA_PATH_MARK is the string that marks the substitution points in a
-@* template.
-@@ LUA_EXECDIR in a Windows path is replaced by the executable's
-@* directory.
-@@ LUA_IGMARK is a mark to ignore all before it when bulding the
-@* luaopen_ function name.
-** CHANGE them if for some reason your system cannot use those
-** characters. (E.g., if one of those characters is a common character
-** in file/directory names.) Probably you do not need to change them.
+@@ LUA_ENV is the name of the variable that holds the current
+@@ environment, used to access global names.
+** CHANGE it if you do not like this name.
 */
-#define LUA_PATHSEP	";"
-#define LUA_PATH_MARK	"?"
-#define LUA_EXECDIR	"!"
-#define LUA_IGMARK	"-"
-
-
-/*
-@@ LUA_INTEGER is the integral type used by lua_pushinteger/lua_tointeger.
-** CHANGE that if ptrdiff_t is not adequate on your machine. (On most
-** machines, ptrdiff_t gives a good choice between int or long.)
-*/
-#define LUA_INTEGER	ptrdiff_t
+#define LUA_ENV		"_ENV"
 
 
 /*
 @@ LUA_API is a mark for all core API functions.
-@@ LUALIB_API is a mark for all standard library functions.
+@@ LUALIB_API is a mark for all auxiliary library functions.
+@@ LUAMOD_API is a mark for all standard library opening functions.
 ** CHANGE them if you need to define those functions in some special way.
 ** For instance, if you want to create one Windows DLL with the core and
 ** the libraries, you may want to use the following definition (define
 ** LUA_BUILD_AS_DLL to get it).
 */
-#if defined(LUA_BUILD_AS_DLL)
+#if defined(LUA_BUILD_AS_DLL)	/* { */
 
-#if defined(LUA_CORE) || defined(LUA_LIB)
+#if defined(LUA_CORE) || defined(LUA_LIB)	/* { */
 #define LUA_API __declspec(dllexport)
-#else
+#else						/* }{ */
 #define LUA_API __declspec(dllimport)
-#endif
+#endif						/* } */
 
-#else
+#else				/* }{ */
 
 #define LUA_API		extern
 
-#endif
+#endif				/* } */
+
 
 /* more often than not the libs go together with the core */
 #define LUALIB_API	LUA_API
+#define LUAMOD_API	LUALIB_API
 
 
 /*
 @@ LUAI_FUNC is a mark for all extern functions that are not to be
 @* exported to outside modules.
-@@ LUAI_DATA is a mark for all extern (const) variables that are not to
-@* be exported to outside modules.
+@@ LUAI_DDEF and LUAI_DDEC are marks for all extern (const) variables
+@* that are not to be exported to outside modules (LUAI_DDEF for
+@* definitions and LUAI_DDEC for declarations).
 ** CHANGE them if you need to mark them in some special way. Elf/gcc
 ** (versions 3.2 and later) mark them as "hidden" to optimize access
-** when Lua is compiled as a shared library.
+** when Lua is compiled as a shared library. Not all elf targets support
+** this attribute. Unfortunately, gcc does not offer a way to check
+** whether the target offers that support, and those without support
+** give a warning about it. To avoid these warnings, change to the
+** default definition.
 */
-#if defined(luaall_c)
+#if defined(luaall_c)		/* { */
 #define LUAI_FUNC	static
-#define LUAI_DATA	/* empty */
+#define LUAI_DDEC	static
+#define LUAI_DDEF	static
 
 #elif defined(__GNUC__) && ((__GNUC__*100 + __GNUC_MINOR__) >= 302) && \
       defined(__ELF__)
 #define LUAI_FUNC	__attribute__((visibility("hidden"))) extern
-#define LUAI_DATA	LUAI_FUNC
+#define LUAI_DDEC	LUAI_FUNC
+#define LUAI_DDEF	/* empty */
 
-#else
+#else				/* }{ */
 #define LUAI_FUNC	extern
-#define LUAI_DATA	extern
-#endif
+#define LUAI_DDEC	extern
+#define LUAI_DDEF	/* empty */
+#endif				/* } */
 
 
 
@@ -211,175 +209,97 @@
 
 
 /*
-** {==================================================================
-** Stand-alone configuration
-** ===================================================================
+@@ luai_writestring/luai_writeline define how 'print' prints its results.
 */
-
-#if defined(lua_c) || defined(luaall_c)
+#include <stdio.h>
+#define luai_writestring(s,l)	fwrite((s), sizeof(char), (l), stdout)
+#define luai_writeline()	(luai_writestring("\n", 1), fflush(stdout))
 
 /*
-@@ lua_stdin_is_tty detects whether the standard input is a 'tty' (that
-@* is, whether we're running lua interactively).
-** CHANGE it if you have a better definition for non-POSIX/non-Windows
-** systems.
+@@ luai_writestringerror defines how to print error messages.
+** (A format string with one argument is enough for Lua...)
 */
-#if defined(LUA_USE_ISATTY)
-#include <unistd.h>
-#define lua_stdin_is_tty()	isatty(0)
-#elif defined(LUA_WIN)
-#include <io.h>
-#include <stdio.h>
-#define lua_stdin_is_tty()	_isatty(_fileno(stdin))
-#else
-#define lua_stdin_is_tty()	1  /* assume stdin is a tty */
-#endif
+#define luai_writestringerror(s,p) \
+	(fprintf(stderr, (s), (p)), fflush(stderr))
+
 
 
-/*
-@@ LUA_PROMPT is the default prompt used by stand-alone Lua.
-@@ LUA_PROMPT2 is the default continuation prompt used by stand-alone Lua.
-** CHANGE them if you want different prompts. (You can also change the
-** prompts dynamically, assigning to globals _PROMPT/_PROMPT2.)
-*/
-#define LUA_PROMPT		"> "
-#define LUA_PROMPT2		">> "
 
 
 /*
-@@ LUA_PROGNAME is the default name for the stand-alone Lua program.
-** CHANGE it if your stand-alone interpreter has a different name and
-** your system is not able to detect that name automatically.
+** {==================================================================
+** Compatibility with previous versions
+** ===================================================================
 */
-#define LUA_PROGNAME		"lua"
-
 
 /*
-@@ LUA_MAXINPUT is the maximum length for an input line in the
-@* stand-alone interpreter.
-** CHANGE it if you need longer lines.
+@@ LUA_COMPAT_ALL controls all compatibility options.
+** You can define it to get all options, or change specific options
+** to fit your specific needs.
 */
-#define LUA_MAXINPUT	512
-
+#if defined(LUA_COMPAT_ALL)	/* { */
 
 /*
-@@ lua_readline defines how to show a prompt and then read a line from
-@* the standard input.
-@@ lua_saveline defines how to "save" a read line in a "history".
-@@ lua_freeline defines how to free a line read by lua_readline.
-** CHANGE them if you want to improve this functionality (e.g., by using
-** GNU readline and history facilities).
+@@ LUA_COMPAT_UNPACK controls the presence of global 'unpack'.
+** You can replace it with 'table.unpack'.
 */
-#if defined(LUA_USE_READLINE)
-#include <stdio.h>
-#include <readline/readline.h>
-#include <readline/history.h>
-#define lua_readline(L,b,p)	((void)L, ((b)=readline(p)) != NULL)
-#define lua_saveline(L,idx) \
-	if (lua_strlen(L,idx) > 0)  /* non-empty line? */ \
-	  add_history(lua_tostring(L, idx));  /* add it to history */
-#define lua_freeline(L,b)	((void)L, free(b))
-#else
-#define lua_readline(L,b,p)	\
-	((void)L, fputs(p, stdout), fflush(stdout),  /* show prompt */ \
-	fgets(b, LUA_MAXINPUT, stdin) != NULL)  /* get line */
-#define lua_saveline(L,idx)	{ (void)L; (void)idx; }
-#define lua_freeline(L,b)	{ (void)L; (void)b; }
-#endif
-
-#endif
-
-/* }================================================================== */
-
+#define LUA_COMPAT_UNPACK
 
 /*
-@@ LUAI_GCPAUSE defines the default pause between garbage-collector cycles
-@* as a percentage.
-** CHANGE it if you want the GC to run faster or slower (higher values
-** mean larger pauses which mean slower collection.) You can also change
-** this value dynamically.
+@@ LUA_COMPAT_LOADERS controls the presence of table 'package.loaders'.
+** You can replace it with 'package.searchers'.
 */
-#define LUAI_GCPAUSE	200  /* 200% (wait memory to double before next GC) */
-
+#define LUA_COMPAT_LOADERS
 
 /*
-@@ LUAI_GCMUL defines the default speed of garbage collection relative to
-@* memory allocation as a percentage.
-** CHANGE it if you want to change the granularity of the garbage
-** collection. (Higher values mean coarser collections. 0 represents
-** infinity, where each step performs a full collection.) You can also
-** change this value dynamically.
+@@ macro 'lua_cpcall' emulates deprecated function lua_cpcall.
+** You can call your C function directly (with light C functions).
 */
-#define LUAI_GCMUL	200 /* GC runs 'twice the speed' of memory allocation */
-
+#define lua_cpcall(L,f,u)  \
+	(lua_pushcfunction(L, (f)), \
+	 lua_pushlightuserdata(L,(u)), \
+	 lua_pcall(L,1,0,0))
 
 
 /*
-@@ LUA_COMPAT_GETN controls compatibility with old getn behavior.
-** CHANGE it (define it) if you want exact compatibility with the
-** behavior of setn/getn in Lua 5.0.
+@@ LUA_COMPAT_LOG10 defines the function 'log10' in the math library.
+** You can rewrite 'log10(x)' as 'log(x, 10)'.
 */
-#undef LUA_COMPAT_GETN
+#define LUA_COMPAT_LOG10
 
 /*
-@@ LUA_COMPAT_LOADLIB controls compatibility about global loadlib.
-** CHANGE it to undefined as soon as you do not need a global 'loadlib'
-** function (the function is still available as 'package.loadlib').
+@@ LUA_COMPAT_LOADSTRING defines the function 'loadstring' in the base
+** library. You can rewrite 'loadstring(s)' as 'load(s)'.
 */
-#undef LUA_COMPAT_LOADLIB
+#define LUA_COMPAT_LOADSTRING
 
 /*
-@@ LUA_COMPAT_VARARG controls compatibility with old vararg feature.
-** CHANGE it to undefined as soon as your programs use only '...' to
-** access vararg parameters (instead of the old 'arg' table).
+@@ LUA_COMPAT_MAXN defines the function 'maxn' in the table library.
 */
-#define LUA_COMPAT_VARARG
+#define LUA_COMPAT_MAXN
 
 /*
-@@ LUA_COMPAT_MOD controls compatibility with old math.mod function.
-** CHANGE it to undefined as soon as your programs use 'math.fmod' or
-** the new '%' operator instead of 'math.mod'.
+@@ The following macros supply trivial compatibility for some
+** changes in the API. The macros themselves document how to
+** change your code to avoid using them.
 */
-#define LUA_COMPAT_MOD
+#define lua_strlen(L,i)		lua_rawlen(L, (i))
 
-/*
-@@ LUA_COMPAT_LSTR controls compatibility with old long string nesting
-@* facility.
-** CHANGE it to 2 if you want the old behaviour, or undefine it to turn
-** off the advisory error when nesting [[...]].
-*/
-#define LUA_COMPAT_LSTR		1
+#define lua_objlen(L,i)		lua_rawlen(L, (i))
 
-/*
-@@ LUA_COMPAT_GFIND controls compatibility with old 'string.gfind' name.
-** CHANGE it to undefined as soon as you rename 'string.gfind' to
-** 'string.gmatch'.
-*/
-#define LUA_COMPAT_GFIND
+#define lua_equal(L,idx1,idx2)		lua_compare(L,(idx1),(idx2),LUA_OPEQ)
+#define lua_lessthan(L,idx1,idx2)	lua_compare(L,(idx1),(idx2),LUA_OPLT)
 
 /*
-@@ LUA_COMPAT_OPENLIB controls compatibility with old 'luaL_openlib'
-@* behavior.
-** CHANGE it to undefined as soon as you replace to 'luaL_register'
-** your uses of 'luaL_openlib'
+@@ LUA_COMPAT_MODULE controls compatibility with previous
+** module functions 'module' (Lua) and 'luaL_register' (C).
 */
-#define LUA_COMPAT_OPENLIB
+#define LUA_COMPAT_MODULE
 
+#endif				/* } */
 
+/* }================================================================== */
 
-/*
-@@ luai_apicheck is the assert macro used by the Lua-C API.
-** CHANGE luai_apicheck if you want Lua to perform some checks in the
-** parameters it gets from API calls. This may slow down the interpreter
-** a bit, but may be quite useful when debugging C code that interfaces
-** with Lua. A useful redefinition is to use assert.h.
-*/
-#if defined(LUA_USE_APICHECK)
-#include <assert.h>
-#define luai_apicheck(L,o)	{ (void)L; assert(o); }
-#else
-#define luai_apicheck(L,o)	{ (void)L; }
-#endif
 
 
 /*
@@ -388,107 +308,62 @@
 ** your machine. Probably you do not need to change this.
 */
 /* avoid overflows in comparison */
-#if INT_MAX-20 < 32760
+#if INT_MAX-20 < 32760		/* { */
 #define LUAI_BITSINT	16
-#elif INT_MAX > 2147483640L
+#elif INT_MAX > 2147483640L	/* }{ */
 /* int has at least 32 bits */
 #define LUAI_BITSINT	32
-#else
+#else				/* }{ */
 #error "you must define LUA_BITSINT with number of bits in an integer"
-#endif
+#endif				/* } */
 
 
 /*
-@@ LUAI_UINT32 is an unsigned integer with at least 32 bits.
-@@ LUAI_INT32 is an signed integer with at least 32 bits.
+@@ LUA_INT32 is an signed integer with exactly 32 bits.
 @@ LUAI_UMEM is an unsigned integer big enough to count the total
 @* memory used by Lua.
 @@ LUAI_MEM is a signed integer big enough to count the total memory
 @* used by Lua.
 ** CHANGE here if for some weird reason the default definitions are not
-** good enough for your machine. (The definitions in the 'else'
-** part always works, but may waste space on machines with 64-bit
-** longs.) Probably you do not need to change this.
+** good enough for your machine. Probably you do not need to change
+** this.
 */
-#if LUAI_BITSINT >= 32
-#define LUAI_UINT32	unsigned int
-#define LUAI_INT32	int
-#define LUAI_MAXINT32	INT_MAX
+#if LUAI_BITSINT >= 32		/* { */
+#define LUA_INT32	int
 #define LUAI_UMEM	size_t
 #define LUAI_MEM	ptrdiff_t
-#else
+#else				/* }{ */
 /* 16-bit ints */
-#define LUAI_UINT32	unsigned long
-#define LUAI_INT32	long
-#define LUAI_MAXINT32	LONG_MAX
+#define LUA_INT32	long
 #define LUAI_UMEM	unsigned long
 #define LUAI_MEM	long
-#endif
-
-
-/*
-@@ LUAI_MAXCALLS limits the number of nested calls.
-** CHANGE it if you need really deep recursive calls. This limit is
-** arbitrary; its only purpose is to stop infinite recursion before
-** exhausting memory.
-*/
-#define LUAI_MAXCALLS	20000
-
-
-/*
-@@ LUAI_MAXCSTACK limits the number of Lua stack slots that a C function
-@* can use.
-** CHANGE it if you need lots of (Lua) stack space for your C
-** functions. This limit is arbitrary; its only purpose is to stop C
-** functions to consume unlimited stack space. (must be smaller than
-** -LUA_REGISTRYINDEX)
-*/
-#define LUAI_MAXCSTACK	8000
-
-
-
-/*
-** {==================================================================
-** CHANGE (to smaller values) the following definitions if your system
-** has a small C stack. (Or you may want to change them to larger
-** values if your system has a large C stack and these limits are
-** too rigid for you.) Some of these constants control the size of
-** stack-allocated arrays used by the compiler or the interpreter, while
-** others limit the maximum number of recursive calls that the compiler
-** or the interpreter can perform. Values too large may cause a C stack
-** overflow for some forms of deep constructs.
-** ===================================================================
-*/
+#endif				/* } */
 
 
 /*
-@@ LUAI_MAXCCALLS is the maximum depth for nested C calls (short) and
-@* syntactical nested non-terminals in a program.
+@@ LUAI_MAXSTACK limits the size of the Lua stack.
+** CHANGE it if you need a different limit. This limit is arbitrary;
+** its only purpose is to stop Lua to consume unlimited stack
+** space (and to reserve some numbers for pseudo-indices).
 */
-#define LUAI_MAXCCALLS		200
-
+#if LUAI_BITSINT >= 32
+#define LUAI_MAXSTACK		1000000
+#else
+#define LUAI_MAXSTACK		15000
+#endif
 
-/*
-@@ LUAI_MAXVARS is the maximum number of local variables per function
-@* (must be smaller than 250).
-*/
-#define LUAI_MAXVARS		200
+/* reserve some space for error handling */
+#define LUAI_FIRSTPSEUDOIDX	(-LUAI_MAXSTACK - 1000)
 
 
-/*
-@@ LUAI_MAXUPVALUES is the maximum number of upvalues per function
-@* (must be smaller than 250).
-*/
-#define LUAI_MAXUPVALUES	60
 
 
 /*
 @@ LUAL_BUFFERSIZE is the buffer size used by the lauxlib buffer system.
+** CHANGE it if it uses too much C-stack space.
 */
 #define LUAL_BUFFERSIZE		BUFSIZ
 
-/* }================================================================== */
-
 
 
 
@@ -516,237 +391,127 @@
 @@ LUA_NUMBER_FMT is the format for writing numbers.
 @@ lua_number2str converts a number to a string.
 @@ LUAI_MAXNUMBER2STR is maximum size of previous conversion.
-@@ lua_str2number converts a string to a number.
 */
 #define LUA_NUMBER_SCAN		"%lf"
 #define LUA_NUMBER_FMT		"%.14g"
 #define lua_number2str(s,n)	sprintf((s), LUA_NUMBER_FMT, (n))
 #define LUAI_MAXNUMBER2STR	32 /* 16 digits, sign, point, and \0 */
-#define lua_str2number(s,p)	strtod((s), (p))
 
 
 /*
-@@ The luai_num* macros define the primitive operations over numbers.
+@@ lua_str2number converts a decimal numeric string to a number.
+@@ lua_strx2number converts an hexadecimal numeric string to a number.
+** In C99, 'strtod' do both conversions. C89, however, has no function
+** to convert floating hexadecimal strings to numbers. For these
+** systems, you can leave 'lua_strx2number' undefined and Lua will
+** provide its own implementation.
 */
-#if defined(LUA_CORE)
-#include <math.h>
-#define luai_numadd(a,b)	((a)+(b))
-#define luai_numsub(a,b)	((a)-(b))
-#define luai_nummul(a,b)	((a)*(b))
-#define luai_numdiv(a,b)	((a)/(b))
-#define luai_nummod(a,b)	((a) - floor((a)/(b))*(b))
-#define luai_numpow(a,b)	(pow(a,b))
-#define luai_numunm(a)		(-(a))
-#define luai_numeq(a,b)		((a)==(b))
-#define luai_numlt(a,b)		((a)<(b))
-#define luai_numle(a,b)		((a)<=(b))
-#define luai_numisnan(a)	(!luai_numeq((a), (a)))
+#define lua_str2number(s,p)	strtod((s), (p))
+
+#if defined(LUA_USE_STRTODHEX)
+#define lua_strx2number(s,p)	strtod((s), (p))
 #endif
 
 
 /*
-@@ lua_number2int is a macro to convert lua_Number to int.
-@@ lua_number2integer is a macro to convert lua_Number to lua_Integer.
-** CHANGE them if you know a faster way to convert a lua_Number to
-** int (with any rounding method and without throwing errors) in your
-** system. In Pentium machines, a naive typecast from double to int
-** in C is extremely slow, so any alternative is worth trying.
+@@ The luai_num* macros define the primitive operations over numbers.
 */
 
-/* On a Pentium, resort to a trick */
-#if defined(LUA_NUMBER_DOUBLE) && !defined(LUA_ANSI) && !defined(__SSE2__) && \
-    (defined(__i386) || defined (_M_IX86) || defined(__i386__))
-
-/* On a Microsoft compiler, use assembler */
-#if defined(_MSC_VER)
-
-#define lua_number2int(i,d)   __asm fld d   __asm fistp i
-#define lua_number2integer(i,n)		lua_number2int(i, n)
-
-/* the next trick should work on any Pentium, but sometimes clashes
-   with a DirectX idiosyncrasy */
-#else
-
-union luai_Cast { double l_d; long l_l; };
-#define lua_number2int(i,d) \
-  { volatile union luai_Cast u; u.l_d = (d) + 6755399441055744.0; (i) = u.l_l; }
-#define lua_number2integer(i,n)		lua_number2int(i, n)
-
+/* the following operations need the math library */
+#if defined(lobject_c) || defined(lvm_c) || defined(luaall_c)
+#include <math.h>
+#define luai_nummod(L,a,b)	((a) - floor((a)/(b))*(b))
+#define luai_numpow(L,a,b)	(pow(a,b))
 #endif
 
-
-/* this option always works, but may be slow */
-#else
-#define lua_number2int(i,d)	((i)=(int)(d))
-#define lua_number2integer(i,d)	((i)=(lua_Integer)(d))
-
+/* these are quite standard operations */
+#if defined(LUA_CORE)
+#define luai_numadd(L,a,b)	((a)+(b))
+#define luai_numsub(L,a,b)	((a)-(b))
+#define luai_nummul(L,a,b)	((a)*(b))
+#define luai_numdiv(L,a,b)	((a)/(b))
+#define luai_numunm(L,a)	(-(a))
+#define luai_numeq(a,b)		((a)==(b))
+#define luai_numlt(L,a,b)	((a)<(b))
+#define luai_numle(L,a,b)	((a)<=(b))
+#define luai_numisnan(L,a)	(!luai_numeq((a), (a)))
 #endif
 
-/* }================================================================== */
 
 
 /*
-@@ LUAI_USER_ALIGNMENT_T is a type that requires maximum alignment.
-** CHANGE it if your system requires alignments larger than double. (For
-** instance, if your system supports long doubles and they must be
-** aligned in 16-byte boundaries, then you should add long double in the
-** union.) Probably you do not need to change this.
+@@ LUA_INTEGER is the integral type used by lua_pushinteger/lua_tointeger.
+** CHANGE that if ptrdiff_t is not adequate on your machine. (On most
+** machines, ptrdiff_t gives a good choice between int or long.)
 */
-#define LUAI_USER_ALIGNMENT_T	union { double u; void *s; long l; }
-
+#define LUA_INTEGER	ptrdiff_t
 
 /*
-@@ LUAI_THROW/LUAI_TRY define how Lua does exception handling.
-** CHANGE them if you prefer to use longjmp/setjmp even with C++
-** or if want/don't to use _longjmp/_setjmp instead of regular
-** longjmp/setjmp. By default, Lua handles errors with exceptions when
-** compiling as C++ code, with _longjmp/_setjmp when asked to use them,
-** and with longjmp/setjmp otherwise.
+@@ LUA_UNSIGNED is the integral type used by lua_pushunsigned/lua_tounsigned.
+** It must have at least 32 bits.
 */
-#if defined(__cplusplus)
-/* C++ exceptions */
-#define LUAI_THROW(L,c)	throw(c)
-#define LUAI_TRY(L,c,a)	try { a } catch(...) \
-	{ if ((c)->status == 0) (c)->status = -1; }
-#define luai_jmpbuf	int  /* dummy variable */
-
-#elif defined(LUA_USE_ULONGJMP)
-/* in Unix, try _longjmp/_setjmp (more efficient) */
-#define LUAI_THROW(L,c)	_longjmp((c)->b, 1)
-#define LUAI_TRY(L,c,a)	if (_setjmp((c)->b) == 0) { a }
-#define luai_jmpbuf	jmp_buf
-
-#else
-/* default handling with long jumps */
-#define LUAI_THROW(L,c)	longjmp((c)->b, 1)
-#define LUAI_TRY(L,c,a)	if (setjmp((c)->b) == 0) { a }
-#define luai_jmpbuf	jmp_buf
+#define LUA_UNSIGNED	unsigned LUA_INT32
 
-#endif
 
+#if defined(LUA_CORE)		/* { */
 
-/*
-@@ LUA_MAXCAPTURES is the maximum number of captures that a pattern
-@* can do during pattern-matching.
-** CHANGE it if you need more captures. This limit is arbitrary.
-*/
-#define LUA_MAXCAPTURES		32
+#if defined(LUA_NUMBER_DOUBLE) && !defined(LUA_ANSI)	/* { */
 
+/* On a Microsoft compiler on a Pentium, use assembler to avoid clashes
+   with a DirectX idiosyncrasy */
+#if defined(_MSC_VER) && defined(M_IX86)		/* { */
 
-/*
-@@ lua_tmpnam is the function that the OS library uses to create a
-@* temporary name.
-@@ LUA_TMPNAMBUFSIZE is the maximum size of a name created by lua_tmpnam.
-** CHANGE them if you have an alternative to tmpnam (which is considered
-** insecure) or if you want the original tmpnam anyway.  By default, Lua
-** uses tmpnam except when POSIX is available, where it uses mkstemp.
-*/
-#if defined(loslib_c) || defined(luaall_c)
-
-#if defined(LUA_USE_MKSTEMP)
-#include <unistd.h>
-#define LUA_TMPNAMBUFSIZE	32
-#define lua_tmpnam(b,e)	{ \
-	strcpy(b, "/tmp/lua_XXXXXX"); \
-	e = mkstemp(b); \
-	if (e != -1) close(e); \
-	e = (e == -1); }
+#define MS_ASMTRICK
 
-#else
-#define LUA_TMPNAMBUFSIZE	L_tmpnam
-#define lua_tmpnam(b,e)		{ e = (tmpnam(b) == NULL); }
-#endif
-
-#endif
+#else				/* }{ */
+/* the next definition uses a trick that should work on any machine
+   using IEEE754 with a 32-bit integer type */
 
+#define LUA_IEEE754TRICK
 
 /*
-@@ lua_popen spawns a new process connected to the current one through
-@* the file streams.
-** CHANGE it if you have a way to implement it in your system.
+@@ LUA_IEEEENDIAN is the endianness of doubles in your machine
+** (0 for little endian, 1 for big endian); if not defined, Lua will
+** check it dynamically.
 */
-#if defined(LUA_USE_POPEN)
-
-#define lua_popen(L,c,m)	((void)L, fflush(NULL), popen(c,m))
-#define lua_pclose(L,file)	((void)L, (pclose(file) != -1))
-
-#elif defined(LUA_WIN)
-
-#define lua_popen(L,c,m)	((void)L, _popen(c,m))
-#define lua_pclose(L,file)	((void)L, (_pclose(file) != -1))
-
-#else
-
-#define lua_popen(L,c,m)	((void)((void)c, m),  \
-		luaL_error(L, LUA_QL("popen") " not supported"), (FILE*)0)
-#define lua_pclose(L,file)		((void)((void)L, file), 0)
-
+/* check for known architectures */
+#if defined(__i386__) || defined(__i386) || defined(__X86__) || \
+    defined (__x86_64)
+#define LUA_IEEEENDIAN	0
+#elif defined(__POWERPC__) || defined(__ppc__)
+#define LUA_IEEEENDIAN	1
 #endif
 
-/*
-@@ LUA_DL_* define which dynamic-library system Lua should use.
-** CHANGE here if Lua has problems choosing the appropriate
-** dynamic-library system for your platform (either Windows' DLL, Mac's
-** dyld, or Unix's dlopen). If your system is some kind of Unix, there
-** is a good chance that it has dlopen, so LUA_DL_DLOPEN will work for
-** it.  To use dlopen you also need to adapt the src/Makefile (probably
-** adding -ldl to the linker options), so Lua does not select it
-** automatically.  (When you change the makefile to add -ldl, you must
-** also add -DLUA_USE_DLOPEN.)
-** If you do not want any kind of dynamic library, undefine all these
-** options.
-** By default, _WIN32 gets LUA_DL_DLL and MAC OS X gets LUA_DL_DYLD.
-*/
-#if defined(LUA_USE_DLOPEN)
-#define LUA_DL_DLOPEN
-#endif
+#endif				/* } */
 
-#if defined(LUA_WIN)
-#define LUA_DL_DLL
-#endif
+#endif			/* } */
 
+#endif			/* } */
 
-/*
-@@ LUAI_EXTRASPACE allows you to add user-specific data in a lua_State
-@* (the data goes just *before* the lua_State pointer).
-** CHANGE (define) this if you really need that. This value must be
-** a multiple of the maximum alignment required for your machine.
-*/
-#define LUAI_EXTRASPACE		0
-
-
-/*
-@@ luai_userstate* allow user-specific actions on threads.
-** CHANGE them if you defined LUAI_EXTRASPACE and need to do something
-** extra when a thread is created/deleted/resumed/yielded.
-*/
-#define luai_userstateopen(L)		((void)L)
-#define luai_userstateclose(L)		((void)L)
-#define luai_userstatethread(L,L1)	((void)L)
-#define luai_userstatefree(L)		((void)L)
-#define luai_userstateresume(L,n)	((void)L)
-#define luai_userstateyield(L,n)	((void)L)
+/* }================================================================== */
 
 
 /*
-@@ LUA_INTFRMLEN is the length modifier for integer conversions
-@* in 'string.format'.
-@@ LUA_INTFRM_T is the integer type correspoding to the previous length
-@* modifier.
-** CHANGE them if your system supports long long or does not support long.
+@@ LUA_NANTRICKLE/LUA_NANTRICKBE controls the use of a trick to pack all
+** types into a single double value, using NaN values to represent
+** non-number values. The trick only works on 32-bit machines (ints and
+** pointers are 32-bit values) with numbers represented as IEEE 754-2008
+** doubles with conventional endianess (12345678 or 87654321), in CPUs
+** that do not produce signaling NaN values (all NaNs are quiet).
 */
+#if defined(LUA_CORE) && \
+    defined(LUA_NUMBER_DOUBLE) && !defined(LUA_ANSI)	/* { */
 
-#if defined(LUA_USELONGLONG)
+/* little-endian architectures that satisfy those conditions */
+#if defined(__i386__) || defined(__i386) || defined(__X86__) || \
+    defined(_M_IX86)
 
-#define LUA_INTFRMLEN		"ll"
-#define LUA_INTFRM_T		long long
+#define LUA_NANTRICKLE
 
-#else
+#endif
 
-#define LUA_INTFRMLEN		"l"
-#define LUA_INTFRM_T		long
+#endif							/* } */
 
-#endif
 
 
 
diff --git a/src/lualib.h b/src/lualib.h
index 469417f..8132da6 100644..100755
--- a/src/lualib.h
+++ b/src/lualib.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lualib.h,v 1.36.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lualib.h,v 1.42 2011/05/25 14:12:28 roberto Exp $
 ** Lua standard libraries
 ** See Copyright Notice in lua.h
 */
@@ -15,37 +15,42 @@
 #define LUA_FILEHANDLE		"FILE*"
 
 
+LUAMOD_API int (luaopen_base) (lua_State *L);
+
 #define LUA_COLIBNAME	"coroutine"
-LUALIB_API int (luaopen_base) (lua_State *L);
+LUAMOD_API int (luaopen_coroutine) (lua_State *L);
 
 #define LUA_TABLIBNAME	"table"
-LUALIB_API int (luaopen_table) (lua_State *L);
+LUAMOD_API int (luaopen_table) (lua_State *L);
 
 #define LUA_IOLIBNAME	"io"
-LUALIB_API int (luaopen_io) (lua_State *L);
+LUAMOD_API int (luaopen_io) (lua_State *L);
 
 #define LUA_OSLIBNAME	"os"
-LUALIB_API int (luaopen_os) (lua_State *L);
+LUAMOD_API int (luaopen_os) (lua_State *L);
 
 #define LUA_STRLIBNAME	"string"
-LUALIB_API int (luaopen_string) (lua_State *L);
+LUAMOD_API int (luaopen_string) (lua_State *L);
+
+#define LUA_BITLIBNAME	"bit32"
+LUAMOD_API int (luaopen_bit32) (lua_State *L);
 
 #define LUA_MATHLIBNAME	"math"
-LUALIB_API int (luaopen_math) (lua_State *L);
+LUAMOD_API int (luaopen_math) (lua_State *L);
 
 #define LUA_DBLIBNAME	"debug"
-LUALIB_API int (luaopen_debug) (lua_State *L);
+LUAMOD_API int (luaopen_debug) (lua_State *L);
 
 #define LUA_LOADLIBNAME	"package"
-LUALIB_API int (luaopen_package) (lua_State *L);
+LUAMOD_API int (luaopen_package) (lua_State *L);
 
 
 /* open all previous libraries */
-LUALIB_API void (luaL_openlibs) (lua_State *L); 
+LUALIB_API void (luaL_openlibs) (lua_State *L);
 
 
 
-#ifndef lua_assert
+#if !defined(lua_assert)
 #define lua_assert(x)	((void)0)
 #endif
 
diff --git a/src/lundump.c b/src/lundump.c
index 8010a45..d7b0ab3 100644..100755
--- a/src/lundump.c
+++ b/src/lundump.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lundump.c,v 2.7.1.4 2008/04/04 19:51:41 roberto Exp $
+** $Id: lundump.c,v 1.70 2011/06/21 12:29:00 lhf Exp $
 ** load precompiled Lua chunks
 ** See Copyright Notice in lua.h
 */
@@ -27,28 +27,24 @@ typedef struct {
  const char* name;
 } LoadState;
 
-#ifdef LUAC_TRUST_BINARIES
-#define IF(c,s)
-#define error(S,s)
-#else
-#define IF(c,s)		if (c) error(S,s)
-
 static void error(LoadState* S, const char* why)
 {
- luaO_pushfstring(S->L,"%s: %s in precompiled chunk",S->name,why);
+ luaO_pushfstring(S->L,"%s: %s precompiled chunk",S->name,why);
  luaD_throw(S->L,LUA_ERRSYNTAX);
 }
-#endif
 
 #define LoadMem(S,b,n,size)	LoadBlock(S,b,(n)*(size))
-#define	LoadByte(S)		(lu_byte)LoadChar(S)
+#define LoadByte(S)		(lu_byte)LoadChar(S)
 #define LoadVar(S,x)		LoadMem(S,&x,1,sizeof(x))
 #define LoadVector(S,b,n,size)	LoadMem(S,b,n,size)
 
+#if !defined(luai_verifycode)
+#define luai_verifycode(L,b,f)	(f)
+#endif
+
 static void LoadBlock(LoadState* S, void* b, size_t size)
 {
- size_t r=luaZ_read(S->Z,b,size);
- IF (r!=0, "unexpected end");
+ if (luaZ_read(S->Z,b,size)!=0) error(S,"truncated");
 }
 
 static int LoadChar(LoadState* S)
@@ -62,7 +58,7 @@ static int LoadInt(LoadState* S)
 {
  int x;
  LoadVar(S,x);
- IF (x<0, "bad integer");
+ if (x<0) error(S,"corrupted");
  return x;
 }
 
@@ -82,7 +78,7 @@ static TString* LoadString(LoadState* S)
  else
  {
   char* s=luaZ_openspace(S->L,S->b,size);
-  LoadBlock(S,s,size);
+  LoadBlock(S,s,size*sizeof(char));
   return luaS_newlstr(S->L,s,size-1);		/* remove trailing '\0' */
  }
 }
@@ -95,7 +91,7 @@ static void LoadCode(LoadState* S, Proto* f)
  LoadVector(S,f->code,n,sizeof(Instruction));
 }
 
-static Proto* LoadFunction(LoadState* S, TString* p);
+static Proto* LoadFunction(LoadState* S);
 
 static void LoadConstants(LoadState* S, Proto* f)
 {
@@ -111,10 +107,10 @@ static void LoadConstants(LoadState* S, Proto* f)
   switch (t)
   {
    case LUA_TNIL:
-   	setnilvalue(o);
+	setnilvalue(o);
 	break;
    case LUA_TBOOLEAN:
-   	setbvalue(o,LoadChar(S)!=0);
+	setbvalue(o,LoadChar(S));
 	break;
    case LUA_TNUMBER:
 	setnvalue(o,LoadNumber(S));
@@ -122,21 +118,33 @@ static void LoadConstants(LoadState* S, Proto* f)
    case LUA_TSTRING:
 	setsvalue2n(S->L,o,LoadString(S));
 	break;
-   default:
-	error(S,"bad constant");
-	break;
   }
  }
  n=LoadInt(S);
  f->p=luaM_newvector(S->L,n,Proto*);
  f->sizep=n;
  for (i=0; i<n; i++) f->p[i]=NULL;
- for (i=0; i<n; i++) f->p[i]=LoadFunction(S,f->source);
+ for (i=0; i<n; i++) f->p[i]=LoadFunction(S);
+}
+
+static void LoadUpvalues(LoadState* S, Proto* f)
+{
+ int i,n;
+ n=LoadInt(S);
+ f->upvalues=luaM_newvector(S->L,n,Upvaldesc);
+ f->sizeupvalues=n;
+ for (i=0; i<n; i++) f->upvalues[i].name=NULL;
+ for (i=0; i<n; i++)
+ {
+  f->upvalues[i].instack=LoadChar(S);
+  f->upvalues[i].idx=LoadChar(S);
+ }
 }
 
 static void LoadDebug(LoadState* S, Proto* f)
 {
  int i,n;
+ f->source=LoadString(S);
  n=LoadInt(S);
  f->lineinfo=luaM_newvector(S->L,n,int);
  f->sizelineinfo=n;
@@ -152,41 +160,43 @@ static void LoadDebug(LoadState* S, Proto* f)
   f->locvars[i].endpc=LoadInt(S);
  }
  n=LoadInt(S);
- f->upvalues=luaM_newvector(S->L,n,TString*);
- f->sizeupvalues=n;
- for (i=0; i<n; i++) f->upvalues[i]=NULL;
- for (i=0; i<n; i++) f->upvalues[i]=LoadString(S);
+ for (i=0; i<n; i++) f->upvalues[i].name=LoadString(S);
 }
 
-static Proto* LoadFunction(LoadState* S, TString* p)
+static Proto* LoadFunction(LoadState* S)
 {
- Proto* f;
- if (++S->L->nCcalls > LUAI_MAXCCALLS) error(S,"code too deep");
- f=luaF_newproto(S->L);
+ Proto* f=luaF_newproto(S->L);
  setptvalue2s(S->L,S->L->top,f); incr_top(S->L);
- f->source=LoadString(S); if (f->source==NULL) f->source=p;
  f->linedefined=LoadInt(S);
  f->lastlinedefined=LoadInt(S);
- f->nups=LoadByte(S);
  f->numparams=LoadByte(S);
  f->is_vararg=LoadByte(S);
  f->maxstacksize=LoadByte(S);
  LoadCode(S,f);
  LoadConstants(S,f);
+ LoadUpvalues(S,f);
  LoadDebug(S,f);
- IF (!luaG_checkcode(f), "bad code");
  S->L->top--;
- S->L->nCcalls--;
  return f;
 }
 
+/* the code below must be consistent with the code in luaU_header */
+#define N0	LUAC_HEADERSIZE
+#define N1	(sizeof(LUA_SIGNATURE)-sizeof(char))
+#define N2	N1+2
+#define N3	N2+6
+
 static void LoadHeader(LoadState* S)
 {
- char h[LUAC_HEADERSIZE];
- char s[LUAC_HEADERSIZE];
+ lu_byte h[LUAC_HEADERSIZE];
+ lu_byte s[LUAC_HEADERSIZE];
  luaU_header(h);
- LoadBlock(S,s,LUAC_HEADERSIZE);
- IF (memcmp(h,s,LUAC_HEADERSIZE)!=0, "bad header");
+ memcpy(s,h,sizeof(char));			/* first char already read */
+ LoadBlock(S,s+sizeof(char),LUAC_HEADERSIZE-sizeof(char));
+ if (memcmp(h,s,N0)==0) return;
+ if (memcmp(h,s,N1)!=0) error(S,"not a");
+ if (memcmp(h,s,N2)!=0) error(S,"version mismatch in");
+ if (memcmp(h,s,N3)!=0) error(S,"incompatible"); else error(S,"corrupted");
 }
 
 /*
@@ -205,23 +215,30 @@ Proto* luaU_undump (lua_State* L, ZIO* Z, Mbuffer* buff, const char* name)
  S.Z=Z;
  S.b=buff;
  LoadHeader(&S);
- return LoadFunction(&S,luaS_newliteral(L,"=?"));
+ return luai_verifycode(L,buff,LoadFunction(&S));
 }
 
+#define MYINT(s)	(s[0]-'0')
+#define VERSION		MYINT(LUA_VERSION_MAJOR)*16+MYINT(LUA_VERSION_MINOR)
+#define FORMAT		0		/* this is the official format */
+
 /*
-* make header
+* make header for precompiled chunks
+* if you change the code below be sure to update LoadHeader and FORMAT above
+* and LUAC_HEADERSIZE in lundump.h
 */
-void luaU_header (char* h)
+void luaU_header (lu_byte* h)
 {
  int x=1;
- memcpy(h,LUA_SIGNATURE,sizeof(LUA_SIGNATURE)-1);
- h+=sizeof(LUA_SIGNATURE)-1;
- *h++=(char)LUAC_VERSION;
- *h++=(char)LUAC_FORMAT;
- *h++=(char)*(char*)&x;				/* endianness */
- *h++=(char)sizeof(int);
- *h++=(char)sizeof(size_t);
- *h++=(char)sizeof(Instruction);
- *h++=(char)sizeof(lua_Number);
- *h++=(char)(((lua_Number)0.5)==0);		/* is lua_Number integral? */
+ memcpy(h,LUA_SIGNATURE,sizeof(LUA_SIGNATURE)-sizeof(char));
+ h+=sizeof(LUA_SIGNATURE)-sizeof(char);
+ *h++=cast_byte(VERSION);
+ *h++=cast_byte(FORMAT);
+ *h++=cast_byte(*(char*)&x);			/* endianness */
+ *h++=cast_byte(sizeof(int));
+ *h++=cast_byte(sizeof(size_t));
+ *h++=cast_byte(sizeof(Instruction));
+ *h++=cast_byte(sizeof(lua_Number));
+ *h++=cast_byte(((lua_Number)0.5)==0);		/* is lua_Number integral? */
+ memcpy(h,LUAC_TAIL,sizeof(LUAC_TAIL)-sizeof(char));
 }
diff --git a/src/lundump.h b/src/lundump.h
index c80189d..b63993f 100644..100755
--- a/src/lundump.h
+++ b/src/lundump.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lundump.h,v 1.37.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lundump.h,v 1.44 2011/05/06 13:35:17 lhf Exp $
 ** load precompiled Lua chunks
 ** See Copyright Notice in lua.h
 */
@@ -14,23 +14,15 @@
 LUAI_FUNC Proto* luaU_undump (lua_State* L, ZIO* Z, Mbuffer* buff, const char* name);
 
 /* make header; from lundump.c */
-LUAI_FUNC void luaU_header (char* h);
+LUAI_FUNC void luaU_header (lu_byte* h);
 
 /* dump one chunk; from ldump.c */
 LUAI_FUNC int luaU_dump (lua_State* L, const Proto* f, lua_Writer w, void* data, int strip);
 
-#ifdef luac_c
-/* print one chunk; from print.c */
-LUAI_FUNC void luaU_print (const Proto* f, int full);
-#endif
-
-/* for header of binary files -- this is Lua 5.1 */
-#define LUAC_VERSION		0x51
-
-/* for header of binary files -- this is the official format */
-#define LUAC_FORMAT		0
+/* data to catch conversion errors */
+#define LUAC_TAIL		"\x19\x93\r\n\x1a\n"
 
-/* size of header of binary files */
-#define LUAC_HEADERSIZE		12
+/* size in bytes of header of binary files */
+#define LUAC_HEADERSIZE		(sizeof(LUA_SIGNATURE)-sizeof(char)+2+6+sizeof(LUAC_TAIL)-sizeof(char))
 
 #endif
diff --git a/src/lvm.c b/src/lvm.c
index 8aeafda..e4f90af 100644..100755
--- a/src/lvm.c
+++ b/src/lvm.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lvm.c,v 2.63.1.4 2009/07/01 21:10:33 roberto Exp $
+** $Id: lvm.c,v 2.141 2011/06/09 18:24:22 roberto Exp $
 ** Lua virtual machine
 ** See Copyright Notice in lua.h
 */
@@ -35,7 +35,7 @@
 const TValue *luaV_tonumber (const TValue *obj, TValue *n) {
   lua_Number num;
   if (ttisnumber(obj)) return obj;
-  if (ttisstring(obj) && luaO_str2d(svalue(obj), &num)) {
+  if (ttisstring(obj) && luaO_str2d(svalue(obj), tsvalue(obj)->len, &num)) {
     setnvalue(n, num);
     return n;
   }
@@ -50,58 +50,52 @@ int luaV_tostring (lua_State *L, StkId obj) {
   else {
     char s[LUAI_MAXNUMBER2STR];
     lua_Number n = nvalue(obj);
-    lua_number2str(s, n);
-    setsvalue2s(L, obj, luaS_new(L, s));
+    int l = lua_number2str(s, n);
+    setsvalue2s(L, obj, luaS_newlstr(L, s, l));
     return 1;
   }
 }
 
 
-static void traceexec (lua_State *L, const Instruction *pc) {
+static void traceexec (lua_State *L) {
+  CallInfo *ci = L->ci;
   lu_byte mask = L->hookmask;
-  const Instruction *oldpc = L->savedpc;
-  L->savedpc = pc;
   if ((mask & LUA_MASKCOUNT) && L->hookcount == 0) {
     resethookcount(L);
-    luaD_callhook(L, LUA_HOOKCOUNT, -1);
+    luaD_hook(L, LUA_HOOKCOUNT, -1);
   }
   if (mask & LUA_MASKLINE) {
-    Proto *p = ci_func(L->ci)->l.p;
-    int npc = pcRel(pc, p);
-    int newline = getline(p, npc);
-    /* call linehook when enter a new function, when jump back (loop),
-       or when enter a new line */
-    if (npc == 0 || pc <= oldpc || newline != getline(p, pcRel(oldpc, p)))
-      luaD_callhook(L, LUA_HOOKLINE, newline);
+    Proto *p = ci_func(ci)->p;
+    int npc = pcRel(ci->u.l.savedpc, p);
+    int newline = getfuncline(p, npc);
+    if (npc == 0 ||  /* call linehook when enter a new function, */
+        ci->u.l.savedpc <= L->oldpc ||  /* when jump back (loop), or when */
+        newline != getfuncline(p, pcRel(L->oldpc, p)))  /* enter a new line */
+      luaD_hook(L, LUA_HOOKLINE, newline);
+  }
+  L->oldpc = ci->u.l.savedpc;
+  if (L->status == LUA_YIELD) {  /* did hook yield? */
+    ci->u.l.savedpc--;  /* undo increment (resume will increment it again) */
+    luaD_throw(L, LUA_YIELD);
   }
 }
 
 
-static void callTMres (lua_State *L, StkId res, const TValue *f,
-                        const TValue *p1, const TValue *p2) {
-  ptrdiff_t result = savestack(L, res);
-  setobj2s(L, L->top, f);  /* push function */
-  setobj2s(L, L->top+1, p1);  /* 1st argument */
-  setobj2s(L, L->top+2, p2);  /* 2nd argument */
-  luaD_checkstack(L, 3);
-  L->top += 3;
-  luaD_call(L, L->top - 3, 1);
-  res = restorestack(L, result);
-  L->top--;
-  setobjs2s(L, res, L->top);
-}
-
-
-
 static void callTM (lua_State *L, const TValue *f, const TValue *p1,
-                    const TValue *p2, const TValue *p3) {
-  setobj2s(L, L->top, f);  /* push function */
-  setobj2s(L, L->top+1, p1);  /* 1st argument */
-  setobj2s(L, L->top+2, p2);  /* 2nd argument */
-  setobj2s(L, L->top+3, p3);  /* 3th argument */
-  luaD_checkstack(L, 4);
-  L->top += 4;
-  luaD_call(L, L->top - 4, 0);
+                    const TValue *p2, TValue *p3, int hasres) {
+  ptrdiff_t result = savestack(L, p3);
+  setobj2s(L, L->top++, f);  /* push function */
+  setobj2s(L, L->top++, p1);  /* 1st argument */
+  setobj2s(L, L->top++, p2);  /* 2nd argument */
+  if (!hasres)  /* no result? 'p3' is third argument */
+    setobj2s(L, L->top++, p3);  /* 3rd argument */
+  luaD_checkstack(L, 0);
+  /* metamethod may yield only when called from Lua code */
+  luaD_call(L, L->top - (4 - hasres), hasres, isLua(L->ci));
+  if (hasres) {  /* if has result, move it to its place */
+    p3 = restorestack(L, result);
+    setobjs2s(L, p3, --L->top);
+  }
 }
 
 
@@ -112,7 +106,7 @@ void luaV_gettable (lua_State *L, const TValue *t, TValue *key, StkId val) {
     if (ttistable(t)) {  /* `t' is a table? */
       Table *h = hvalue(t);
       const TValue *res = luaH_get(h, key); /* do a primitive get */
-      if (!ttisnil(res) ||  /* result is no nil? */
+      if (!ttisnil(res) ||  /* result is not nil? */
           (tm = fasttm(L, h->metatable, TM_INDEX)) == NULL) { /* or no TM? */
         setobj2s(L, val, res);
         return;
@@ -122,10 +116,10 @@ void luaV_gettable (lua_State *L, const TValue *t, TValue *key, StkId val) {
     else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_INDEX)))
       luaG_typeerror(L, t, "index");
     if (ttisfunction(tm)) {
-      callTMres(L, val, tm, t, key);
+      callTM(L, tm, t, key, val, 1);
       return;
     }
-    t = tm;  /* else repeat with `tm' */ 
+    t = tm;  /* else repeat with 'tm' */
   }
   luaG_runerror(L, "loop in gettable");
 }
@@ -139,10 +133,10 @@ void luaV_settable (lua_State *L, const TValue *t, TValue *key, StkId val) {
     if (ttistable(t)) {  /* `t' is a table? */
       Table *h = hvalue(t);
       TValue *oldval = luaH_set(L, h, key); /* do a primitive set */
-      if (!ttisnil(oldval) ||  /* result is no nil? */
+      if (!ttisnil(oldval) ||  /* result is not nil? */
           (tm = fasttm(L, h->metatable, TM_NEWINDEX)) == NULL) { /* or no TM? */
         setobj2t(L, oldval, val);
-        luaC_barriert(L, h, val);
+        luaC_barrierback(L, obj2gco(h), val);
         return;
       }
       /* else will try the tag method */
@@ -150,10 +144,10 @@ void luaV_settable (lua_State *L, const TValue *t, TValue *key, StkId val) {
     else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_NEWINDEX)))
       luaG_typeerror(L, t, "index");
     if (ttisfunction(tm)) {
-      callTM(L, tm, t, key, val);
+      callTM(L, tm, t, key, val, 0);
       return;
     }
-    /* else repeat with `tm' */
+    /* else repeat with 'tm' */
     setobj(L, &temp, tm);  /* avoid pointing inside table (may rehash) */
     t = &temp;
   }
@@ -167,12 +161,12 @@ static int call_binTM (lua_State *L, const TValue *p1, const TValue *p2,
   if (ttisnil(tm))
     tm = luaT_gettmbyobj(L, p2, event);  /* try second operand */
   if (ttisnil(tm)) return 0;
-  callTMres(L, res, tm, p1, p2);
+  callTM(L, tm, p1, p2, res, 1);
   return 1;
 }
 
 
-static const TValue *get_compTM (lua_State *L, Table *mt1, Table *mt2,
+static const TValue *get_equalTM (lua_State *L, Table *mt1, Table *mt2,
                                   TMS event) {
   const TValue *tm1 = fasttm(L, mt1, event);
   const TValue *tm2;
@@ -180,7 +174,7 @@ static const TValue *get_compTM (lua_State *L, Table *mt1, Table *mt2,
   if (mt1 == mt2) return tm1;  /* same metatables => same metamethods */
   tm2 = fasttm(L, mt2, event);
   if (tm2 == NULL) return NULL;  /* no metamethod */
-  if (luaO_rawequalObj(tm1, tm2))  /* same metamethods? */
+  if (luaV_rawequalobj(tm1, tm2))  /* same metamethods? */
     return tm1;
   return NULL;
 }
@@ -188,14 +182,10 @@ static const TValue *get_compTM (lua_State *L, Table *mt1, Table *mt2,
 
 static int call_orderTM (lua_State *L, const TValue *p1, const TValue *p2,
                          TMS event) {
-  const TValue *tm1 = luaT_gettmbyobj(L, p1, event);
-  const TValue *tm2;
-  if (ttisnil(tm1)) return -1;  /* no metamethod? */
-  tm2 = luaT_gettmbyobj(L, p2, event);
-  if (!luaO_rawequalObj(tm1, tm2))  /* different metamethods? */
-    return -1;
-  callTMres(L, L->top, tm1, p1, p2);
-  return !l_isfalse(L->top);
+  if (!call_binTM(L, p1, p2, L->top, event))
+    return -1;  /* no metamethod */
+  else
+    return !l_isfalse(L->top);
 }
 
 
@@ -223,11 +213,9 @@ static int l_strcmp (const TString *ls, const TString *rs) {
 
 int luaV_lessthan (lua_State *L, const TValue *l, const TValue *r) {
   int res;
-  if (ttype(l) != ttype(r))
-    return luaG_ordererror(L, l, r);
-  else if (ttisnumber(l))
-    return luai_numlt(nvalue(l), nvalue(r));
-  else if (ttisstring(l))
+  if (ttisnumber(l) && ttisnumber(r))
+    return luai_numlt(L, nvalue(l), nvalue(r));
+  else if (ttisstring(l) && ttisstring(r))
     return l_strcmp(rawtsvalue(l), rawtsvalue(r)) < 0;
   else if ((res = call_orderTM(L, l, r, TM_LT)) != -1)
     return res;
@@ -235,13 +223,11 @@ int luaV_lessthan (lua_State *L, const TValue *l, const TValue *r) {
 }
 
 
-static int lessequal (lua_State *L, const TValue *l, const TValue *r) {
+int luaV_lessequal (lua_State *L, const TValue *l, const TValue *r) {
   int res;
-  if (ttype(l) != ttype(r))
-    return luaG_ordererror(L, l, r);
-  else if (ttisnumber(l))
-    return luai_numle(nvalue(l), nvalue(r));
-  else if (ttisstring(l))
+  if (ttisnumber(l) && ttisnumber(r))
+    return luai_numle(L, nvalue(l), nvalue(r));
+  else if (ttisstring(l) && ttisstring(r))
     return l_strcmp(rawtsvalue(l), rawtsvalue(r)) <= 0;
   else if ((res = call_orderTM(L, l, r, TM_LE)) != -1)  /* first try `le' */
     return res;
@@ -251,97 +237,235 @@ static int lessequal (lua_State *L, const TValue *l, const TValue *r) {
 }
 
 
-int luaV_equalval (lua_State *L, const TValue *t1, const TValue *t2) {
+/*
+** equality of Lua values. L == NULL means raw equality (no metamethods)
+*/
+int luaV_equalobj_ (lua_State *L, const TValue *t1, const TValue *t2) {
   const TValue *tm;
-  lua_assert(ttype(t1) == ttype(t2));
+  lua_assert(ttisequal(t1, t2));
   switch (ttype(t1)) {
     case LUA_TNIL: return 1;
     case LUA_TNUMBER: return luai_numeq(nvalue(t1), nvalue(t2));
     case LUA_TBOOLEAN: return bvalue(t1) == bvalue(t2);  /* true must be 1 !! */
     case LUA_TLIGHTUSERDATA: return pvalue(t1) == pvalue(t2);
+    case LUA_TLCF: return fvalue(t1) == fvalue(t2);
+    case LUA_TSTRING: return eqstr(rawtsvalue(t1), rawtsvalue(t2));
     case LUA_TUSERDATA: {
       if (uvalue(t1) == uvalue(t2)) return 1;
-      tm = get_compTM(L, uvalue(t1)->metatable, uvalue(t2)->metatable,
-                         TM_EQ);
+      else if (L == NULL) return 0;
+      tm = get_equalTM(L, uvalue(t1)->metatable, uvalue(t2)->metatable, TM_EQ);
       break;  /* will try TM */
     }
     case LUA_TTABLE: {
       if (hvalue(t1) == hvalue(t2)) return 1;
-      tm = get_compTM(L, hvalue(t1)->metatable, hvalue(t2)->metatable, TM_EQ);
+      else if (L == NULL) return 0;
+      tm = get_equalTM(L, hvalue(t1)->metatable, hvalue(t2)->metatable, TM_EQ);
       break;  /* will try TM */
     }
-    default: return gcvalue(t1) == gcvalue(t2);
+    default:
+      lua_assert(iscollectable(t1));
+      return gcvalue(t1) == gcvalue(t2);
   }
   if (tm == NULL) return 0;  /* no TM? */
-  callTMres(L, L->top, tm, t1, t2);  /* call TM */
+  callTM(L, tm, t1, t2, L->top, 1);  /* call TM */
   return !l_isfalse(L->top);
 }
 
 
-void luaV_concat (lua_State *L, int total, int last) {
+void luaV_concat (lua_State *L, int total) {
+  lua_assert(total >= 2);
   do {
-    StkId top = L->base + last + 1;
+    StkId top = L->top;
     int n = 2;  /* number of elements handled in this pass (at least 2) */
     if (!(ttisstring(top-2) || ttisnumber(top-2)) || !tostring(L, top-1)) {
       if (!call_binTM(L, top-2, top-1, top-2, TM_CONCAT))
         luaG_concaterror(L, top-2, top-1);
-    } else if (tsvalue(top-1)->len == 0)  /* second op is empty? */
-      (void)tostring(L, top - 2);  /* result is first op (as string) */
+    }
+    else if (tsvalue(top-1)->len == 0)  /* second operand is empty? */
+      (void)tostring(L, top - 2);  /* result is first operand */
+    else if (ttisstring(top-2) && tsvalue(top-2)->len == 0) {
+      setsvalue2s(L, top-2, rawtsvalue(top-1));  /* result is second op. */
+    }
     else {
-      /* at least two string values; get as many as possible */
+      /* at least two non-empty string values; get as many as possible */
       size_t tl = tsvalue(top-1)->len;
       char *buffer;
       int i;
       /* collect total length */
-      for (n = 1; n < total && tostring(L, top-n-1); n++) {
-        size_t l = tsvalue(top-n-1)->len;
-        if (l >= MAX_SIZET - tl) luaG_runerror(L, "string length overflow");
+      for (i = 1; i < total && tostring(L, top-i-1); i++) {
+        size_t l = tsvalue(top-i-1)->len;
+        if (l >= (MAX_SIZET/sizeof(char)) - tl)
+          luaG_runerror(L, "string length overflow");
         tl += l;
       }
       buffer = luaZ_openspace(L, &G(L)->buff, tl);
       tl = 0;
-      for (i=n; i>0; i--) {  /* concat all strings */
+      n = i;
+      do {  /* concat all strings */
         size_t l = tsvalue(top-i)->len;
-        memcpy(buffer+tl, svalue(top-i), l);
+        memcpy(buffer+tl, svalue(top-i), l * sizeof(char));
         tl += l;
-      }
+      } while (--i > 0);
       setsvalue2s(L, top-n, luaS_newlstr(L, buffer, tl));
     }
-    total -= n-1;  /* got `n' strings to create 1 new */
-    last -= n-1;
+    total -= n-1;  /* got 'n' strings to create 1 new */
+    L->top -= n-1;  /* popped 'n' strings and pushed one */
   } while (total > 1);  /* repeat until only 1 result left */
 }
 
 
-static void Arith (lua_State *L, StkId ra, const TValue *rb,
-                   const TValue *rc, TMS op) {
+void luaV_objlen (lua_State *L, StkId ra, const TValue *rb) {
+  const TValue *tm;
+  switch (ttypenv(rb)) {
+    case LUA_TTABLE: {
+      Table *h = hvalue(rb);
+      tm = fasttm(L, h->metatable, TM_LEN);
+      if (tm) break;  /* metamethod? break switch to call it */
+      setnvalue(ra, cast_num(luaH_getn(h)));  /* else primitive len */
+      return;
+    }
+    case LUA_TSTRING: {
+      setnvalue(ra, cast_num(tsvalue(rb)->len));
+      return;
+    }
+    default: {  /* try metamethod */
+      tm = luaT_gettmbyobj(L, rb, TM_LEN);
+      if (ttisnil(tm))  /* no metamethod? */
+        luaG_typeerror(L, rb, "get length of");
+      break;
+    }
+  }
+  callTM(L, tm, rb, rb, ra, 1);
+}
+
+
+void luaV_arith (lua_State *L, StkId ra, const TValue *rb,
+                 const TValue *rc, TMS op) {
   TValue tempb, tempc;
   const TValue *b, *c;
   if ((b = luaV_tonumber(rb, &tempb)) != NULL &&
       (c = luaV_tonumber(rc, &tempc)) != NULL) {
-    lua_Number nb = nvalue(b), nc = nvalue(c);
-    switch (op) {
-      case TM_ADD: setnvalue(ra, luai_numadd(nb, nc)); break;
-      case TM_SUB: setnvalue(ra, luai_numsub(nb, nc)); break;
-      case TM_MUL: setnvalue(ra, luai_nummul(nb, nc)); break;
-      case TM_DIV: setnvalue(ra, luai_numdiv(nb, nc)); break;
-      case TM_MOD: setnvalue(ra, luai_nummod(nb, nc)); break;
-      case TM_POW: setnvalue(ra, luai_numpow(nb, nc)); break;
-      case TM_UNM: setnvalue(ra, luai_numunm(nb)); break;
-      default: lua_assert(0); break;
-    }
+    lua_Number res = luaO_arith(op - TM_ADD + LUA_OPADD, nvalue(b), nvalue(c));
+    setnvalue(ra, res);
   }
   else if (!call_binTM(L, rb, rc, ra, op))
     luaG_aritherror(L, rb, rc);
 }
 
 
+/*
+** check whether cached closure in prototype 'p' may be reused, that is,
+** whether there is a cached closure with the same upvalues needed by
+** new closure to be created.
+*/
+static Closure *getcached (Proto *p, UpVal **encup, StkId base) {
+  Closure *c = p->cache;
+  if (c != NULL) {  /* is there a cached closure? */
+    int nup = p->sizeupvalues;
+    Upvaldesc *uv = p->upvalues;
+    int i;
+    for (i = 0; i < nup; i++) {  /* check whether it has right upvalues */
+      TValue *v = uv[i].instack ? base + uv[i].idx : encup[uv[i].idx]->v;
+      if (c->l.upvals[i]->v != v)
+        return NULL;  /* wrong upvalue; cannot reuse closure */
+    }
+  }
+  return c;  /* return cached closure (or NULL if no cached closure) */
+}
+
+
+/*
+** create a new Lua closure, push it in the stack, and initialize
+** its upvalues. Note that the call to 'luaC_barrierproto' must come
+** before the assignment to 'p->cache', as the function needs the
+** original value of that field.
+*/
+static void pushclosure (lua_State *L, Proto *p, UpVal **encup, StkId base,
+                         StkId ra) {
+  int nup = p->sizeupvalues;
+  Upvaldesc *uv = p->upvalues;
+  int i;
+  Closure *ncl = luaF_newLclosure(L, p);
+  setclLvalue(L, ra, ncl);  /* anchor new closure in stack */
+  for (i = 0; i < nup; i++) {  /* fill in its upvalues */
+    if (uv[i].instack)  /* upvalue refers to local variable? */
+      ncl->l.upvals[i] = luaF_findupval(L, base + uv[i].idx);
+    else  /* get upvalue from enclosing function */
+      ncl->l.upvals[i] = encup[uv[i].idx];
+  }
+  luaC_barrierproto(L, p, ncl);
+  p->cache = ncl;  /* save it on cache for reuse */
+}
+
+
+/*
+** finish execution of an opcode interrupted by an yield
+*/
+void luaV_finishOp (lua_State *L) {
+  CallInfo *ci = L->ci;
+  StkId base = ci->u.l.base;
+  Instruction inst = *(ci->u.l.savedpc - 1);  /* interrupted instruction */
+  OpCode op = GET_OPCODE(inst);
+  switch (op) {  /* finish its execution */
+    case OP_ADD: case OP_SUB: case OP_MUL: case OP_DIV:
+    case OP_MOD: case OP_POW: case OP_UNM: case OP_LEN:
+    case OP_GETTABUP: case OP_GETTABLE: case OP_SELF: {
+      setobjs2s(L, base + GETARG_A(inst), --L->top);
+      break;
+    }
+    case OP_LE: case OP_LT: case OP_EQ: {
+      int res = !l_isfalse(L->top - 1);
+      L->top--;
+      /* metamethod should not be called when operand is K */
+      lua_assert(!ISK(GETARG_B(inst)));
+      if (op == OP_LE &&  /* "<=" using "<" instead? */
+          ttisnil(luaT_gettmbyobj(L, base + GETARG_B(inst), TM_LE)))
+        res = !res;  /* invert result */
+      lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_JMP);
+      if (res != GETARG_A(inst))  /* condition failed? */
+        ci->u.l.savedpc++;  /* skip jump instruction */
+      break;
+    }
+    case OP_CONCAT: {
+      StkId top = L->top - 1;  /* top when 'call_binTM' was called */
+      int b = GETARG_B(inst);      /* first element to concatenate */
+      int total = cast_int(top - 1 - (base + b));  /* yet to concatenate */
+      setobj2s(L, top - 2, top);  /* put TM result in proper position */
+      if (total > 1) {  /* are there elements to concat? */
+        L->top = top - 1;  /* top is one after last element (at top-2) */
+        luaV_concat(L, total);  /* concat them (may yield again) */
+      }
+      /* move final result to final position */
+      setobj2s(L, ci->u.l.base + GETARG_A(inst), L->top - 1);
+      L->top = ci->top;  /* restore top */
+      break;
+    }
+    case OP_TFORCALL: {
+      lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_TFORLOOP);
+      L->top = ci->top;  /* correct top */
+      break;
+    }
+    case OP_CALL: {
+      if (GETARG_C(inst) - 1 >= 0)  /* nresults >= 0? */
+        L->top = ci->top;  /* adjust results */
+      break;
+    }
+    case OP_TAILCALL: case OP_SETTABUP:  case OP_SETTABLE:
+      break;
+    default: lua_assert(0);
+  }
+}
+
+
 
 /*
 ** some macros for common tasks in `luaV_execute'
 */
 
-#define runtime_check(L, c)	{ if (!(c)) break; }
+#if !defined luai_runtimecheck
+#define luai_runtimecheck(L, c)		/* void */
+#endif
+
 
 #define RA(i)	(base+GETARG_A(i))
 /* to be used after possible stack reallocation */
@@ -351,13 +475,23 @@ static void Arith (lua_State *L, StkId ra, const TValue *rb,
 	ISK(GETARG_B(i)) ? k+INDEXK(GETARG_B(i)) : base+GETARG_B(i))
 #define RKC(i)	check_exp(getCMode(GET_OPCODE(i)) == OpArgK, \
 	ISK(GETARG_C(i)) ? k+INDEXK(GETARG_C(i)) : base+GETARG_C(i))
-#define KBx(i)	check_exp(getBMode(GET_OPCODE(i)) == OpArgK, k+GETARG_Bx(i))
+#define KBx(i)  \
+  (k + (GETARG_Bx(i) != 0 ? GETARG_Bx(i) - 1 : GETARG_Ax(*ci->u.l.savedpc++)))
+
+
+/* execute a jump instruction */
+#define dojump(ci,i,e) \
+  { int a = GETARG_A(i); \
+    if (a > 0) luaF_close(L, ci->u.l.base + a - 1); \
+    ci->u.l.savedpc += GETARG_sBx(i) + e; }
 
+/* for test instructions, execute the jump instruction that follows it */
+#define donextjump(ci)	{ i = *ci->u.l.savedpc; dojump(ci, i, 1); }
 
-#define dojump(L,pc,i)	{(pc) += (i); luai_threadyield(L);}
 
+#define Protect(x)	{ {x;}; base = ci->u.l.base; }
 
-#define Protect(x)	{ L->savedpc = pc; {x;}; base = L->base; }
+#define checkGC(L,c)	Protect(luaC_condGC(L, c); luai_threadyield(L);)
 
 
 #define arith_op(op,tm) { \
@@ -365,401 +499,355 @@ static void Arith (lua_State *L, StkId ra, const TValue *rb,
         TValue *rc = RKC(i); \
         if (ttisnumber(rb) && ttisnumber(rc)) { \
           lua_Number nb = nvalue(rb), nc = nvalue(rc); \
-          setnvalue(ra, op(nb, nc)); \
+          setnvalue(ra, op(L, nb, nc)); \
         } \
-        else \
-          Protect(Arith(L, ra, rb, rc, tm)); \
-      }
+        else { Protect(luaV_arith(L, ra, rb, rc, tm)); } }
 
 
+#define vmdispatch(o)	switch(o)
+#define vmcase(l,b)	case l: {b}  break;
 
-void luaV_execute (lua_State *L, int nexeccalls) {
+void luaV_execute (lua_State *L) {
+  CallInfo *ci = L->ci;
   LClosure *cl;
-  StkId base;
   TValue *k;
-  const Instruction *pc;
- reentry:  /* entry point */
-  lua_assert(isLua(L->ci));
-  pc = L->savedpc;
-  cl = &clvalue(L->ci->func)->l;
-  base = L->base;
+  StkId base;
+ newframe:  /* reentry point when frame changes (call/return) */
+  lua_assert(ci == L->ci);
+  cl = clLvalue(ci->func);
   k = cl->p->k;
+  base = ci->u.l.base;
   /* main loop of interpreter */
   for (;;) {
-    const Instruction i = *pc++;
+    Instruction i = *(ci->u.l.savedpc++);
     StkId ra;
     if ((L->hookmask & (LUA_MASKLINE | LUA_MASKCOUNT)) &&
         (--L->hookcount == 0 || L->hookmask & LUA_MASKLINE)) {
-      traceexec(L, pc);
-      if (L->status == LUA_YIELD) {  /* did hook yield? */
-        L->savedpc = pc - 1;
-        return;
-      }
-      base = L->base;
+      Protect(traceexec(L));
     }
     /* warning!! several calls may realloc the stack and invalidate `ra' */
     ra = RA(i);
-    lua_assert(base == L->base && L->base == L->ci->base);
-    lua_assert(base <= L->top && L->top <= L->stack + L->stacksize);
-    lua_assert(L->top == L->ci->top || luaG_checkopenop(i));
-    switch (GET_OPCODE(i)) {
-      case OP_MOVE: {
+    lua_assert(base == ci->u.l.base);
+    lua_assert(base <= L->top && L->top < L->stack + L->stacksize);
+    vmdispatch (GET_OPCODE(i)) {
+      vmcase(OP_MOVE,
         setobjs2s(L, ra, RB(i));
-        continue;
-      }
-      case OP_LOADK: {
-        setobj2s(L, ra, KBx(i));
-        continue;
-      }
-      case OP_LOADBOOL: {
+      )
+      vmcase(OP_LOADK,
+        TValue *rb = k + GETARG_Bx(i);
+        setobj2s(L, ra, rb);
+      )
+      vmcase(OP_LOADKX,
+        TValue *rb;
+        lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_EXTRAARG);
+        rb = k + GETARG_Ax(*ci->u.l.savedpc++);
+        setobj2s(L, ra, rb);
+      )
+      vmcase(OP_LOADBOOL,
         setbvalue(ra, GETARG_B(i));
-        if (GETARG_C(i)) pc++;  /* skip next instruction (if C) */
-        continue;
-      }
-      case OP_LOADNIL: {
-        TValue *rb = RB(i);
+        if (GETARG_C(i)) ci->u.l.savedpc++;  /* skip next instruction (if C) */
+      )
+      vmcase(OP_LOADNIL,
+        int b = GETARG_B(i);
         do {
-          setnilvalue(rb--);
-        } while (rb >= ra);
-        continue;
-      }
-      case OP_GETUPVAL: {
+          setnilvalue(ra++);
+        } while (b--);
+      )
+      vmcase(OP_GETUPVAL,
         int b = GETARG_B(i);
         setobj2s(L, ra, cl->upvals[b]->v);
-        continue;
-      }
-      case OP_GETGLOBAL: {
-        TValue g;
-        TValue *rb = KBx(i);
-        sethvalue(L, &g, cl->env);
-        lua_assert(ttisstring(rb));
-        Protect(luaV_gettable(L, &g, rb, ra));
-        continue;
-      }
-      case OP_GETTABLE: {
+      )
+      vmcase(OP_GETTABUP,
+        int b = GETARG_B(i);
+        Protect(luaV_gettable(L, cl->upvals[b]->v, RKC(i), ra));
+      )
+      vmcase(OP_GETTABLE,
         Protect(luaV_gettable(L, RB(i), RKC(i), ra));
-        continue;
-      }
-      case OP_SETGLOBAL: {
-        TValue g;
-        sethvalue(L, &g, cl->env);
-        lua_assert(ttisstring(KBx(i)));
-        Protect(luaV_settable(L, &g, KBx(i), ra));
-        continue;
-      }
-      case OP_SETUPVAL: {
+      )
+      vmcase(OP_SETTABUP,
+        int a = GETARG_A(i);
+        Protect(luaV_settable(L, cl->upvals[a]->v, RKB(i), RKC(i)));
+      )
+      vmcase(OP_SETUPVAL,
         UpVal *uv = cl->upvals[GETARG_B(i)];
         setobj(L, uv->v, ra);
         luaC_barrier(L, uv, ra);
-        continue;
-      }
-      case OP_SETTABLE: {
+      )
+      vmcase(OP_SETTABLE,
         Protect(luaV_settable(L, ra, RKB(i), RKC(i)));
-        continue;
-      }
-      case OP_NEWTABLE: {
+      )
+      vmcase(OP_NEWTABLE,
         int b = GETARG_B(i);
         int c = GETARG_C(i);
-        sethvalue(L, ra, luaH_new(L, luaO_fb2int(b), luaO_fb2int(c)));
-        Protect(luaC_checkGC(L));
-        continue;
-      }
-      case OP_SELF: {
+        Table *t = luaH_new(L);
+        sethvalue(L, ra, t);
+        if (b != 0 || c != 0)
+          luaH_resize(L, t, luaO_fb2int(b), luaO_fb2int(c));
+        checkGC(L,
+          L->top = ra + 1;  /* limit of live values */
+          luaC_step(L);
+          L->top = ci->top;  /* restore top */
+        )
+      )
+      vmcase(OP_SELF,
         StkId rb = RB(i);
         setobjs2s(L, ra+1, rb);
         Protect(luaV_gettable(L, rb, RKC(i), ra));
-        continue;
-      }
-      case OP_ADD: {
+      )
+      vmcase(OP_ADD,
         arith_op(luai_numadd, TM_ADD);
-        continue;
-      }
-      case OP_SUB: {
+      )
+      vmcase(OP_SUB,
         arith_op(luai_numsub, TM_SUB);
-        continue;
-      }
-      case OP_MUL: {
+      )
+      vmcase(OP_MUL,
         arith_op(luai_nummul, TM_MUL);
-        continue;
-      }
-      case OP_DIV: {
+      )
+      vmcase(OP_DIV,
         arith_op(luai_numdiv, TM_DIV);
-        continue;
-      }
-      case OP_MOD: {
+      )
+      vmcase(OP_MOD,
         arith_op(luai_nummod, TM_MOD);
-        continue;
-      }
-      case OP_POW: {
+      )
+      vmcase(OP_POW,
         arith_op(luai_numpow, TM_POW);
-        continue;
-      }
-      case OP_UNM: {
+      )
+      vmcase(OP_UNM,
         TValue *rb = RB(i);
         if (ttisnumber(rb)) {
           lua_Number nb = nvalue(rb);
-          setnvalue(ra, luai_numunm(nb));
+          setnvalue(ra, luai_numunm(L, nb));
         }
         else {
-          Protect(Arith(L, ra, rb, rb, TM_UNM));
+          Protect(luaV_arith(L, ra, rb, rb, TM_UNM));
         }
-        continue;
-      }
-      case OP_NOT: {
-        int res = l_isfalse(RB(i));  /* next assignment may change this value */
+      )
+      vmcase(OP_NOT,
+        TValue *rb = RB(i);
+        int res = l_isfalse(rb);  /* next assignment may change this value */
         setbvalue(ra, res);
-        continue;
-      }
-      case OP_LEN: {
-        const TValue *rb = RB(i);
-        switch (ttype(rb)) {
-          case LUA_TTABLE: {
-            setnvalue(ra, cast_num(luaH_getn(hvalue(rb))));
-            break;
-          }
-          case LUA_TSTRING: {
-            setnvalue(ra, cast_num(tsvalue(rb)->len));
-            break;
-          }
-          default: {  /* try metamethod */
-            Protect(
-              if (!call_binTM(L, rb, luaO_nilobject, ra, TM_LEN))
-                luaG_typeerror(L, rb, "get length of");
-            )
-          }
-        }
-        continue;
-      }
-      case OP_CONCAT: {
+      )
+      vmcase(OP_LEN,
+        Protect(luaV_objlen(L, ra, RB(i)));
+      )
+      vmcase(OP_CONCAT,
         int b = GETARG_B(i);
         int c = GETARG_C(i);
-        Protect(luaV_concat(L, c-b+1, c); luaC_checkGC(L));
-        setobjs2s(L, RA(i), base+b);
-        continue;
-      }
-      case OP_JMP: {
-        dojump(L, pc, GETARG_sBx(i));
-        continue;
-      }
-      case OP_EQ: {
+        StkId rb;
+        L->top = base + c + 1;  /* mark the end of concat operands */
+        Protect(luaV_concat(L, c - b + 1));
+        ra = RA(i);  /* 'luav_concat' may invoke TMs and move the stack */
+        rb = b + base;
+        setobjs2s(L, ra, rb);
+        checkGC(L,
+          L->top = (ra >= rb ? ra + 1 : rb);  /* limit of live values */
+          luaC_step(L);
+        )
+        L->top = ci->top;  /* restore top */
+      )
+      vmcase(OP_JMP,
+        dojump(ci, i, 0);
+      )
+      vmcase(OP_EQ,
         TValue *rb = RKB(i);
         TValue *rc = RKC(i);
         Protect(
-          if (equalobj(L, rb, rc) == GETARG_A(i))
-            dojump(L, pc, GETARG_sBx(*pc));
+          if (equalobj(L, rb, rc) != GETARG_A(i))
+            ci->u.l.savedpc++;
+          else
+            donextjump(ci);
         )
-        pc++;
-        continue;
-      }
-      case OP_LT: {
+      )
+      vmcase(OP_LT,
         Protect(
-          if (luaV_lessthan(L, RKB(i), RKC(i)) == GETARG_A(i))
-            dojump(L, pc, GETARG_sBx(*pc));
+          if (luaV_lessthan(L, RKB(i), RKC(i)) != GETARG_A(i))
+            ci->u.l.savedpc++;
+          else
+            donextjump(ci);
         )
-        pc++;
-        continue;
-      }
-      case OP_LE: {
+      )
+      vmcase(OP_LE,
         Protect(
-          if (lessequal(L, RKB(i), RKC(i)) == GETARG_A(i))
-            dojump(L, pc, GETARG_sBx(*pc));
+          if (luaV_lessequal(L, RKB(i), RKC(i)) != GETARG_A(i))
+            ci->u.l.savedpc++;
+          else
+            donextjump(ci);
         )
-        pc++;
-        continue;
-      }
-      case OP_TEST: {
-        if (l_isfalse(ra) != GETARG_C(i))
-          dojump(L, pc, GETARG_sBx(*pc));
-        pc++;
-        continue;
-      }
-      case OP_TESTSET: {
+      )
+      vmcase(OP_TEST,
+        if (GETARG_C(i) ? l_isfalse(ra) : !l_isfalse(ra))
+            ci->u.l.savedpc++;
+          else
+          donextjump(ci);
+      )
+      vmcase(OP_TESTSET,
         TValue *rb = RB(i);
-        if (l_isfalse(rb) != GETARG_C(i)) {
+        if (GETARG_C(i) ? l_isfalse(rb) : !l_isfalse(rb))
+          ci->u.l.savedpc++;
+        else {
           setobjs2s(L, ra, rb);
-          dojump(L, pc, GETARG_sBx(*pc));
+          donextjump(ci);
         }
-        pc++;
-        continue;
-      }
-      case OP_CALL: {
+      )
+      vmcase(OP_CALL,
         int b = GETARG_B(i);
         int nresults = GETARG_C(i) - 1;
         if (b != 0) L->top = ra+b;  /* else previous instruction set top */
-        L->savedpc = pc;
-        switch (luaD_precall(L, ra, nresults)) {
-          case PCRLUA: {
-            nexeccalls++;
-            goto reentry;  /* restart luaV_execute over new Lua function */
-          }
-          case PCRC: {
-            /* it was a C function (`precall' called it); adjust results */
-            if (nresults >= 0) L->top = L->ci->top;
-            base = L->base;
-            continue;
-          }
-          default: {
-            return;  /* yield */
-          }
+        if (luaD_precall(L, ra, nresults)) {  /* C function? */
+          if (nresults >= 0) L->top = ci->top;  /* adjust results */
+          base = ci->u.l.base;
         }
-      }
-      case OP_TAILCALL: {
+        else {  /* Lua function */
+          ci = L->ci;
+          ci->callstatus |= CIST_REENTRY;
+          goto newframe;  /* restart luaV_execute over new Lua function */
+        }
+      )
+      vmcase(OP_TAILCALL,
         int b = GETARG_B(i);
         if (b != 0) L->top = ra+b;  /* else previous instruction set top */
-        L->savedpc = pc;
         lua_assert(GETARG_C(i) - 1 == LUA_MULTRET);
-        switch (luaD_precall(L, ra, LUA_MULTRET)) {
-          case PCRLUA: {
-            /* tail call: put new frame in place of previous one */
-            CallInfo *ci = L->ci - 1;  /* previous frame */
-            int aux;
-            StkId func = ci->func;
-            StkId pfunc = (ci+1)->func;  /* previous function index */
-            if (L->openupval) luaF_close(L, ci->base);
-            L->base = ci->base = ci->func + ((ci+1)->base - pfunc);
-            for (aux = 0; pfunc+aux < L->top; aux++)  /* move frame down */
-              setobjs2s(L, func+aux, pfunc+aux);
-            ci->top = L->top = func+aux;  /* correct top */
-            lua_assert(L->top == L->base + clvalue(func)->l.p->maxstacksize);
-            ci->savedpc = L->savedpc;
-            ci->tailcalls++;  /* one more call lost */
-            L->ci--;  /* remove new frame */
-            goto reentry;
-          }
-          case PCRC: {  /* it was a C function (`precall' called it) */
-            base = L->base;
-            continue;
-          }
-          default: {
-            return;  /* yield */
-          }
+        if (luaD_precall(L, ra, LUA_MULTRET))  /* C function? */
+          base = ci->u.l.base;
+        else {
+          /* tail call: put called frame (n) in place of caller one (o) */
+          CallInfo *nci = L->ci;  /* called frame */
+          CallInfo *oci = nci->previous;  /* caller frame */
+          StkId nfunc = nci->func;  /* called function */
+          StkId ofunc = oci->func;  /* caller function */
+          /* last stack slot filled by 'precall' */
+          StkId lim = nci->u.l.base + getproto(nfunc)->numparams;
+          int aux;
+          /* close all upvalues from previous call */
+          if (cl->p->sizep > 0) luaF_close(L, oci->u.l.base);
+          /* move new frame into old one */
+          for (aux = 0; nfunc + aux < lim; aux++)
+            setobjs2s(L, ofunc + aux, nfunc + aux);
+          oci->u.l.base = ofunc + (nci->u.l.base - nfunc);  /* correct base */
+          oci->top = L->top = ofunc + (L->top - nfunc);  /* correct top */
+          oci->u.l.savedpc = nci->u.l.savedpc;
+          oci->callstatus |= CIST_TAIL;  /* function was tail called */
+          ci = L->ci = oci;  /* remove new frame */
+          lua_assert(L->top == oci->u.l.base + getproto(ofunc)->maxstacksize);
+          goto newframe;  /* restart luaV_execute over new Lua function */
         }
-      }
-      case OP_RETURN: {
+      )
+      vmcase(OP_RETURN,
         int b = GETARG_B(i);
         if (b != 0) L->top = ra+b-1;
-        if (L->openupval) luaF_close(L, base);
-        L->savedpc = pc;
+        if (cl->p->sizep > 0) luaF_close(L, base);
         b = luaD_poscall(L, ra);
-        if (--nexeccalls == 0)  /* was previous function running `here'? */
-          return;  /* no: return */
-        else {  /* yes: continue its execution */
-          if (b) L->top = L->ci->top;
-          lua_assert(isLua(L->ci));
-          lua_assert(GET_OPCODE(*((L->ci)->savedpc - 1)) == OP_CALL);
-          goto reentry;
+        if (!(ci->callstatus & CIST_REENTRY))  /* 'ci' still the called one */
+          return;  /* external invocation: return */
+        else {  /* invocation via reentry: continue execution */
+          ci = L->ci;
+          if (b) L->top = ci->top;
+          lua_assert(isLua(ci));
+          lua_assert(GET_OPCODE(*((ci)->u.l.savedpc - 1)) == OP_CALL);
+          goto newframe;  /* restart luaV_execute over new Lua function */
         }
-      }
-      case OP_FORLOOP: {
+      )
+      vmcase(OP_FORLOOP,
         lua_Number step = nvalue(ra+2);
-        lua_Number idx = luai_numadd(nvalue(ra), step); /* increment index */
+        lua_Number idx = luai_numadd(L, nvalue(ra), step); /* increment index */
         lua_Number limit = nvalue(ra+1);
-        if (luai_numlt(0, step) ? luai_numle(idx, limit)
-                                : luai_numle(limit, idx)) {
-          dojump(L, pc, GETARG_sBx(i));  /* jump back */
+        if (luai_numlt(L, 0, step) ? luai_numle(L, idx, limit)
+                                   : luai_numle(L, limit, idx)) {
+          ci->u.l.savedpc += GETARG_sBx(i);  /* jump back */
           setnvalue(ra, idx);  /* update internal index... */
           setnvalue(ra+3, idx);  /* ...and external index */
         }
-        continue;
-      }
-      case OP_FORPREP: {
+      )
+      vmcase(OP_FORPREP,
         const TValue *init = ra;
         const TValue *plimit = ra+1;
         const TValue *pstep = ra+2;
-        L->savedpc = pc;  /* next steps may throw errors */
         if (!tonumber(init, ra))
           luaG_runerror(L, LUA_QL("for") " initial value must be a number");
         else if (!tonumber(plimit, ra+1))
           luaG_runerror(L, LUA_QL("for") " limit must be a number");
         else if (!tonumber(pstep, ra+2))
           luaG_runerror(L, LUA_QL("for") " step must be a number");
-        setnvalue(ra, luai_numsub(nvalue(ra), nvalue(pstep)));
-        dojump(L, pc, GETARG_sBx(i));
-        continue;
-      }
-      case OP_TFORLOOP: {
+        setnvalue(ra, luai_numsub(L, nvalue(ra), nvalue(pstep)));
+        ci->u.l.savedpc += GETARG_sBx(i);
+      )
+      vmcase(OP_TFORCALL,
         StkId cb = ra + 3;  /* call base */
         setobjs2s(L, cb+2, ra+2);
         setobjs2s(L, cb+1, ra+1);
         setobjs2s(L, cb, ra);
-        L->top = cb+3;  /* func. + 2 args (state and index) */
-        Protect(luaD_call(L, cb, GETARG_C(i)));
-        L->top = L->ci->top;
-        cb = RA(i) + 3;  /* previous call may change the stack */
-        if (!ttisnil(cb)) {  /* continue loop? */
-          setobjs2s(L, cb-1, cb);  /* save control variable */
-          dojump(L, pc, GETARG_sBx(*pc));  /* jump back */
+        L->top = cb + 3;  /* func. + 2 args (state and index) */
+        Protect(luaD_call(L, cb, GETARG_C(i), 1));
+        L->top = ci->top;
+        i = *(ci->u.l.savedpc++);  /* go to next instruction */
+        ra = RA(i);
+        lua_assert(GET_OPCODE(i) == OP_TFORLOOP);
+        goto l_tforloop;
+      )
+      vmcase(OP_TFORLOOP,
+        l_tforloop:
+        if (!ttisnil(ra + 1)) {  /* continue loop? */
+          setobjs2s(L, ra, ra + 1);  /* save control variable */
+           ci->u.l.savedpc += GETARG_sBx(i);  /* jump back */
         }
-        pc++;
-        continue;
-      }
-      case OP_SETLIST: {
+      )
+      vmcase(OP_SETLIST,
         int n = GETARG_B(i);
         int c = GETARG_C(i);
         int last;
         Table *h;
-        if (n == 0) {
-          n = cast_int(L->top - ra) - 1;
-          L->top = L->ci->top;
+        if (n == 0) n = cast_int(L->top - ra) - 1;
+        if (c == 0) {
+          lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_EXTRAARG);
+          c = GETARG_Ax(*ci->u.l.savedpc++);
         }
-        if (c == 0) c = cast_int(*pc++);
-        runtime_check(L, ttistable(ra));
+        luai_runtimecheck(L, ttistable(ra));
         h = hvalue(ra);
         last = ((c-1)*LFIELDS_PER_FLUSH) + n;
         if (last > h->sizearray)  /* needs more space? */
-          luaH_resizearray(L, h, last);  /* pre-alloc it at once */
+          luaH_resizearray(L, h, last);  /* pre-allocate it at once */
         for (; n > 0; n--) {
           TValue *val = ra+n;
-          setobj2t(L, luaH_setnum(L, h, last--), val);
-          luaC_barriert(L, h, val);
-        }
-        continue;
-      }
-      case OP_CLOSE: {
-        luaF_close(L, ra);
-        continue;
-      }
-      case OP_CLOSURE: {
-        Proto *p;
-        Closure *ncl;
-        int nup, j;
-        p = cl->p->p[GETARG_Bx(i)];
-        nup = p->nups;
-        ncl = luaF_newLclosure(L, nup, cl->env);
-        ncl->l.p = p;
-        for (j=0; j<nup; j++, pc++) {
-          if (GET_OPCODE(*pc) == OP_GETUPVAL)
-            ncl->l.upvals[j] = cl->upvals[GETARG_B(*pc)];
-          else {
-            lua_assert(GET_OPCODE(*pc) == OP_MOVE);
-            ncl->l.upvals[j] = luaF_findupval(L, base + GETARG_B(*pc));
-          }
+          setobj2t(L, luaH_setint(L, h, last--), val);
+          luaC_barrierback(L, obj2gco(h), val);
         }
-        setclvalue(L, ra, ncl);
-        Protect(luaC_checkGC(L));
-        continue;
-      }
-      case OP_VARARG: {
+        L->top = ci->top;  /* correct top (in case of previous open call) */
+      )
+      vmcase(OP_CLOSURE,
+        Proto *p = cl->p->p[GETARG_Bx(i)];
+        Closure *ncl = getcached(p, cl->upvals, base);  /* cached closure */
+        if (ncl == NULL)  /* no match? */
+          pushclosure(L, p, cl->upvals, base, ra);  /* create a new one */
+        else
+          setclLvalue(L, ra, ncl);  /* push cashed closure */
+        checkGC(L,
+          L->top = ra + 1;  /* limit of live values */
+          luaC_step(L);
+          L->top = ci->top;  /* restore top */
+        )
+      )
+      vmcase(OP_VARARG,
         int b = GETARG_B(i) - 1;
         int j;
-        CallInfo *ci = L->ci;
-        int n = cast_int(ci->base - ci->func) - cl->p->numparams - 1;
-        if (b == LUA_MULTRET) {
+        int n = cast_int(base - ci->func) - cl->p->numparams - 1;
+        if (b < 0) {  /* B == 0? */
+          b = n;  /* get all var. arguments */
           Protect(luaD_checkstack(L, n));
           ra = RA(i);  /* previous call may change the stack */
-          b = n;
           L->top = ra + n;
         }
         for (j = 0; j < b; j++) {
           if (j < n) {
-            setobjs2s(L, ra + j, ci->base - n + j);
+            setobjs2s(L, ra + j, base - n + j);
           }
           else {
             setnilvalue(ra + j);
           }
         }
-        continue;
-      }
+      )
+      vmcase(OP_EXTRAARG,
+        lua_assert(0);
+      )
     }
   }
 }
diff --git a/src/lvm.h b/src/lvm.h
index bfe4f56..ec35822 100644..100755
--- a/src/lvm.h
+++ b/src/lvm.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lvm.h,v 2.5.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lvm.h,v 2.17 2011/05/31 18:27:56 roberto Exp $
 ** Lua virtual machine
 ** See Copyright Notice in lua.h
 */
@@ -13,24 +13,33 @@
 #include "ltm.h"
 
 
-#define tostring(L,o) ((ttype(o) == LUA_TSTRING) || (luaV_tostring(L, o)))
+#define tostring(L,o) (ttisstring(o) || (luaV_tostring(L, o)))
 
-#define tonumber(o,n)	(ttype(o) == LUA_TNUMBER || \
-                         (((o) = luaV_tonumber(o,n)) != NULL))
+#define tonumber(o,n)	(ttisnumber(o) || (((o) = luaV_tonumber(o,n)) != NULL))
 
-#define equalobj(L,o1,o2) \
-	(ttype(o1) == ttype(o2) && luaV_equalval(L, o1, o2))
+#define equalobj(L,o1,o2)  (ttisequal(o1, o2) && luaV_equalobj_(L, o1, o2))
+
+#define luaV_rawequalobj(t1,t2)  \
+        (ttisequal(t1,t2) && luaV_equalobj_(NULL,t1,t2))
+
+
+/* not to called directly */
+LUAI_FUNC int luaV_equalobj_ (lua_State *L, const TValue *t1, const TValue *t2);
 
 
 LUAI_FUNC int luaV_lessthan (lua_State *L, const TValue *l, const TValue *r);
-LUAI_FUNC int luaV_equalval (lua_State *L, const TValue *t1, const TValue *t2);
+LUAI_FUNC int luaV_lessequal (lua_State *L, const TValue *l, const TValue *r);
 LUAI_FUNC const TValue *luaV_tonumber (const TValue *obj, TValue *n);
 LUAI_FUNC int luaV_tostring (lua_State *L, StkId obj);
 LUAI_FUNC void luaV_gettable (lua_State *L, const TValue *t, TValue *key,
                                             StkId val);
 LUAI_FUNC void luaV_settable (lua_State *L, const TValue *t, TValue *key,
                                             StkId val);
-LUAI_FUNC void luaV_execute (lua_State *L, int nexeccalls);
-LUAI_FUNC void luaV_concat (lua_State *L, int total, int last);
+LUAI_FUNC void luaV_finishOp (lua_State *L);
+LUAI_FUNC void luaV_execute (lua_State *L);
+LUAI_FUNC void luaV_concat (lua_State *L, int total);
+LUAI_FUNC void luaV_arith (lua_State *L, StkId ra, const TValue *rb,
+                           const TValue *rc, TMS op);
+LUAI_FUNC void luaV_objlen (lua_State *L, StkId ra, const TValue *rb);
 
 #endif
diff --git a/src/lzio.c b/src/lzio.c
index 293edd5..7d2677b 100644..100755
--- a/src/lzio.c
+++ b/src/lzio.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lzio.c,v 1.31.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lzio.c,v 1.33 2011/02/23 13:13:10 roberto Exp $
 ** a generic input stream interface
 ** See Copyright Notice in lua.h
 */
@@ -25,26 +25,14 @@ int luaZ_fill (ZIO *z) {
   lua_unlock(L);
   buff = z->reader(L, z->data, &size);
   lua_lock(L);
-  if (buff == NULL || size == 0) return EOZ;
-  z->n = size - 1;
+  if (buff == NULL || size == 0)
+    return EOZ;
+  z->n = size - 1;  /* discount char being returned */
   z->p = buff;
   return char2int(*(z->p++));
 }
 
 
-int luaZ_lookahead (ZIO *z) {
-  if (z->n == 0) {
-    if (luaZ_fill(z) == EOZ)
-      return EOZ;
-    else {
-      z->n++;  /* luaZ_fill removed first byte; put back it */
-      z->p--;
-    }
-  }
-  return char2int(*z->p);
-}
-
-
 void luaZ_init (lua_State *L, ZIO *z, lua_Reader reader, void *data) {
   z->L = L;
   z->reader = reader;
@@ -58,8 +46,14 @@ void luaZ_init (lua_State *L, ZIO *z, lua_Reader reader, void *data) {
 size_t luaZ_read (ZIO *z, void *b, size_t n) {
   while (n) {
     size_t m;
-    if (luaZ_lookahead(z) == EOZ)
-      return n;  /* return number of missing bytes */
+    if (z->n == 0) {  /* no bytes in buffer? */
+      if (luaZ_fill(z) == EOZ)  /* try to read more */
+        return n;  /* no more input; return number of missing bytes */
+      else {
+        z->n++;  /* luaZ_fill consumed first byte; put it back */
+        z->p--;
+      }
+    }
     m = (n <= z->n) ? n : z->n;  /* min. between n and z->n */
     memcpy(b, z->p, m);
     z->n -= m;
diff --git a/src/lzio.h b/src/lzio.h
index 51d695d..4174986 100644..100755
--- a/src/lzio.h
+++ b/src/lzio.h
@@ -1,5 +1,5 @@
 /*
-** $Id: lzio.h,v 1.21.1.1 2007/12/27 13:02:25 roberto Exp $
+** $Id: lzio.h,v 1.24 2011/02/23 13:13:10 roberto Exp $
 ** Buffered streams
 ** See Copyright Notice in lua.h
 */
@@ -21,6 +21,9 @@ typedef struct Zio ZIO;
 
 #define zgetc(z)  (((z)->n--)>0 ?  char2int(*(z)->p++) : luaZ_fill(z))
 
+#define zungetc(z)	((z)->n++, (z)->p--)
+
+
 typedef struct Mbuffer {
   char *buffer;
   size_t n;
@@ -47,7 +50,6 @@ LUAI_FUNC char *luaZ_openspace (lua_State *L, Mbuffer *buff, size_t n);
 LUAI_FUNC void luaZ_init (lua_State *L, ZIO *z, lua_Reader reader,
                                         void *data);
 LUAI_FUNC size_t luaZ_read (ZIO* z, void* b, size_t n);	/* read next n bytes */
-LUAI_FUNC int luaZ_lookahead (ZIO *z);
 
 
 
@@ -56,7 +58,7 @@ LUAI_FUNC int luaZ_lookahead (ZIO *z);
 struct Zio {
   size_t n;			/* bytes still unread */
   const char *p;		/* current position in buffer */
-  lua_Reader reader;
+  lua_Reader reader;		/* reader function */
   void* data;			/* additional data */
   lua_State *L;			/* Lua state (for reader) */
 };
diff --git a/src/print.c b/src/print.c
deleted file mode 100644
index e240cfc..0000000
--- a/src/print.c
+++ /dev/null
@@ -1,227 +0,0 @@
-/*
-** $Id: print.c,v 1.55a 2006/05/31 13:30:05 lhf Exp $
-** print bytecodes
-** See Copyright Notice in lua.h
-*/
-
-#include <ctype.h>
-#include <stdio.h>
-
-#define luac_c
-#define LUA_CORE
-
-#include "ldebug.h"
-#include "lobject.h"
-#include "lopcodes.h"
-#include "lundump.h"
-
-#define PrintFunction	luaU_print
-
-#define Sizeof(x)	((int)sizeof(x))
-#define VOID(p)		((const void*)(p))
-
-static void PrintString(const TString* ts)
-{
- const char* s=getstr(ts);
- size_t i,n=ts->tsv.len;
- putchar('"');
- for (i=0; i<n; i++)
- {
-  int c=s[i];
-  switch (c)
-  {
-   case '"': printf("\\\""); break;
-   case '\\': printf("\\\\"); break;
-   case '\a': printf("\\a"); break;
-   case '\b': printf("\\b"); break;
-   case '\f': printf("\\f"); break;
-   case '\n': printf("\\n"); break;
-   case '\r': printf("\\r"); break;
-   case '\t': printf("\\t"); break;
-   case '\v': printf("\\v"); break;
-   default:	if (isprint((unsigned char)c))
-   			putchar(c);
-		else
-			printf("\\%03u",(unsigned char)c);
-  }
- }
- putchar('"');
-}
-
-static void PrintConstant(const Proto* f, int i)
-{
- const TValue* o=&f->k[i];
- switch (ttype(o))
- {
-  case LUA_TNIL:
-	printf("nil");
-	break;
-  case LUA_TBOOLEAN:
-	printf(bvalue(o) ? "true" : "false");
-	break;
-  case LUA_TNUMBER:
-	printf(LUA_NUMBER_FMT,nvalue(o));
-	break;
-  case LUA_TSTRING:
-	PrintString(rawtsvalue(o));
-	break;
-  default:				/* cannot happen */
-	printf("? type=%d",ttype(o));
-	break;
- }
-}
-
-static void PrintCode(const Proto* f)
-{
- const Instruction* code=f->code;
- int pc,n=f->sizecode;
- for (pc=0; pc<n; pc++)
- {
-  Instruction i=code[pc];
-  OpCode o=GET_OPCODE(i);
-  int a=GETARG_A(i);
-  int b=GETARG_B(i);
-  int c=GETARG_C(i);
-  int bx=GETARG_Bx(i);
-  int sbx=GETARG_sBx(i);
-  int line=getline(f,pc);
-  printf("\t%d\t",pc+1);
-  if (line>0) printf("[%d]\t",line); else printf("[-]\t");
-  printf("%-9s\t",luaP_opnames[o]);
-  switch (getOpMode(o))
-  {
-   case iABC:
-    printf("%d",a);
-    if (getBMode(o)!=OpArgN) printf(" %d",ISK(b) ? (-1-INDEXK(b)) : b);
-    if (getCMode(o)!=OpArgN) printf(" %d",ISK(c) ? (-1-INDEXK(c)) : c);
-    break;
-   case iABx:
-    if (getBMode(o)==OpArgK) printf("%d %d",a,-1-bx); else printf("%d %d",a,bx);
-    break;
-   case iAsBx:
-    if (o==OP_JMP) printf("%d",sbx); else printf("%d %d",a,sbx);
-    break;
-  }
-  switch (o)
-  {
-   case OP_LOADK:
-    printf("\t; "); PrintConstant(f,bx);
-    break;
-   case OP_GETUPVAL:
-   case OP_SETUPVAL:
-    printf("\t; %s", (f->sizeupvalues>0) ? getstr(f->upvalues[b]) : "-");
-    break;
-   case OP_GETGLOBAL:
-   case OP_SETGLOBAL:
-    printf("\t; %s",svalue(&f->k[bx]));
-    break;
-   case OP_GETTABLE:
-   case OP_SELF:
-    if (ISK(c)) { printf("\t; "); PrintConstant(f,INDEXK(c)); }
-    break;
-   case OP_SETTABLE:
-   case OP_ADD:
-   case OP_SUB:
-   case OP_MUL:
-   case OP_DIV:
-   case OP_POW:
-   case OP_EQ:
-   case OP_LT:
-   case OP_LE:
-    if (ISK(b) || ISK(c))
-    {
-     printf("\t; ");
-     if (ISK(b)) PrintConstant(f,INDEXK(b)); else printf("-");
-     printf(" ");
-     if (ISK(c)) PrintConstant(f,INDEXK(c)); else printf("-");
-    }
-    break;
-   case OP_JMP:
-   case OP_FORLOOP:
-   case OP_FORPREP:
-    printf("\t; to %d",sbx+pc+2);
-    break;
-   case OP_CLOSURE:
-    printf("\t; %p",VOID(f->p[bx]));
-    break;
-   case OP_SETLIST:
-    if (c==0) printf("\t; %d",(int)code[++pc]);
-    else printf("\t; %d",c);
-    break;
-   default:
-    break;
-  }
-  printf("\n");
- }
-}
-
-#define SS(x)	(x==1)?"":"s"
-#define S(x)	x,SS(x)
-
-static void PrintHeader(const Proto* f)
-{
- const char* s=getstr(f->source);
- if (*s=='@' || *s=='=')
-  s++;
- else if (*s==LUA_SIGNATURE[0])
-  s="(bstring)";
- else
-  s="(string)";
- printf("\n%s <%s:%d,%d> (%d instruction%s, %d bytes at %p)\n",
- 	(f->linedefined==0)?"main":"function",s,
-	f->linedefined,f->lastlinedefined,
-	S(f->sizecode),f->sizecode*Sizeof(Instruction),VOID(f));
- printf("%d%s param%s, %d slot%s, %d upvalue%s, ",
-	f->numparams,f->is_vararg?"+":"",SS(f->numparams),
-	S(f->maxstacksize),S(f->nups));
- printf("%d local%s, %d constant%s, %d function%s\n",
-	S(f->sizelocvars),S(f->sizek),S(f->sizep));
-}
-
-static void PrintConstants(const Proto* f)
-{
- int i,n=f->sizek;
- printf("constants (%d) for %p:\n",n,VOID(f));
- for (i=0; i<n; i++)
- {
-  printf("\t%d\t",i+1);
-  PrintConstant(f,i);
-  printf("\n");
- }
-}
-
-static void PrintLocals(const Proto* f)
-{
- int i,n=f->sizelocvars;
- printf("locals (%d) for %p:\n",n,VOID(f));
- for (i=0; i<n; i++)
- {
-  printf("\t%d\t%s\t%d\t%d\n",
-  i,getstr(f->locvars[i].varname),f->locvars[i].startpc+1,f->locvars[i].endpc+1);
- }
-}
-
-static void PrintUpvalues(const Proto* f)
-{
- int i,n=f->sizeupvalues;
- printf("upvalues (%d) for %p:\n",n,VOID(f));
- if (f->upvalues==NULL) return;
- for (i=0; i<n; i++)
- {
-  printf("\t%d\t%s\n",i,getstr(f->upvalues[i]));
- }
-}
-
-void PrintFunction(const Proto* f, int full)
-{
- int i,n=f->sizep;
- PrintHeader(f);
- PrintCode(f);
- if (full)
- {
-  PrintConstants(f);
-  PrintLocals(f);
-  PrintUpvalues(f);
- }
- for (i=0; i<n; i++) PrintFunction(f->p[i],full);
-}
diff --git a/test/README b/test/README
deleted file mode 100644
index 0c7f38b..0000000
--- a/test/README
+++ /dev/null
@@ -1,26 +0,0 @@
-These are simple tests for Lua.  Some of them contain useful code.
-They are meant to be run to make sure Lua is built correctly and also
-to be read, to see how Lua programs look.
-
-Here is a one-line summary of each program:
-
-   bisect.lua		bisection method for solving non-linear equations
-   cf.lua		temperature conversion table (celsius to farenheit)
-   echo.lua             echo command line arguments
-   env.lua              environment variables as automatic global variables
-   factorial.lua	factorial without recursion
-   fib.lua		fibonacci function with cache
-   fibfor.lua		fibonacci numbers with coroutines and generators
-   globals.lua		report global variable usage
-   hello.lua		the first program in every language
-   life.lua		Conway's Game of Life
-   luac.lua	 	bare-bones luac
-   printf.lua		an implementation of printf
-   readonly.lua		make global variables readonly
-   sieve.lua		the sieve of of Eratosthenes programmed with coroutines
-   sort.lua		two implementations of a sort function
-   table.lua		make table, grouping all data for the same item
-   trace-calls.lua	trace calls
-   trace-globals.lua	trace assigments to global variables
-   xd.lua		hex dump
-
diff --git a/test/bisect.lua b/test/bisect.lua
deleted file mode 100644
index f91e69b..0000000
--- a/test/bisect.lua
+++ /dev/null
@@ -1,27 +0,0 @@
--- bisection method for solving non-linear equations
-
-delta=1e-6	-- tolerance
-
-function bisect(f,a,b,fa,fb)
- local c=(a+b)/2
- io.write(n," c=",c," a=",a," b=",b,"\n")
- if c==a or c==b or math.abs(a-b)<delta then return c,b-a end
- n=n+1
- local fc=f(c)
- if fa*fc<0 then return bisect(f,a,c,fa,fc) else return bisect(f,c,b,fc,fb) end
-end
-
--- find root of f in the inverval [a,b]. needs f(a)*f(b)<0
-function solve(f,a,b)
- n=0
- local z,e=bisect(f,a,b,f(a),f(b))
- io.write(string.format("after %d steps, root is %.17g with error %.1e, f=%.1e\n",n,z,e,f(z)))
-end
-
--- our function
-function f(x)
- return x*x*x-x-1
-end
-
--- find zero in [1,2]
-solve(f,1,2)
diff --git a/test/cf.lua b/test/cf.lua
deleted file mode 100644
index 8cda54b..0000000
--- a/test/cf.lua
+++ /dev/null
@@ -1,16 +0,0 @@
--- temperature conversion table (celsius to farenheit)
-
-for c0=-20,50-1,10 do
-	io.write("C ")
-	for c=c0,c0+10-1 do
-		io.write(string.format("%3.0f ",c))
-	end
-	io.write("\n")
-	
-	io.write("F ")
-	for c=c0,c0+10-1 do
-		f=(9/5)*c+32
-		io.write(string.format("%3.0f ",f))
-	end
-	io.write("\n\n")
-end
diff --git a/test/echo.lua b/test/echo.lua
deleted file mode 100644
index 4313439..0000000
--- a/test/echo.lua
+++ /dev/null
@@ -1,5 +0,0 @@
--- echo command line arguments
-
-for i=0,table.getn(arg) do
- print(i,arg[i])
-end
diff --git a/test/env.lua b/test/env.lua
deleted file mode 100644
index 9e62a57..0000000
--- a/test/env.lua
+++ /dev/null
@@ -1,7 +0,0 @@
--- read environment variables as if they were global variables
-
-local f=function (t,i) return os.getenv(i) end
-setmetatable(getfenv(),{__index=f})
-
--- an example
-print(a,USER,PATH)
diff --git a/test/factorial.lua b/test/factorial.lua
deleted file mode 100644
index 7c4cf0f..0000000
--- a/test/factorial.lua
+++ /dev/null
@@ -1,32 +0,0 @@
--- function closures are powerful
-
--- traditional fixed-point operator from functional programming
-Y = function (g)
-      local a = function (f) return f(f) end
-      return a(function (f)
-                 return g(function (x)
-                             local c=f(f)
-                             return c(x)
-                           end)
-               end)
-end
-
-
--- factorial without recursion
-F = function (f)
-      return function (n)
-               if n == 0 then return 1
-               else return n*f(n-1) end
-             end
-    end
-
-factorial = Y(F)   -- factorial is the fixed point of F
-
--- now test it
-function test(x)
-	io.write(x,"! = ",factorial(x),"\n")
-end
-
-for n=0,16 do
-	test(n)
-end
diff --git a/test/fib.lua b/test/fib.lua
deleted file mode 100644
index 97a921b..0000000
--- a/test/fib.lua
+++ /dev/null
@@ -1,40 +0,0 @@
--- fibonacci function with cache
-
--- very inefficient fibonacci function
-function fib(n)
-	N=N+1
-	if n<2 then
-		return n
-	else
-		return fib(n-1)+fib(n-2)
-	end
-end
-
--- a general-purpose value cache
-function cache(f)
-	local c={}
-	return function (x)
-		local y=c[x]
-		if not y then
-			y=f(x)
-			c[x]=y
-		end
-		return y
-	end
-end
-
--- run and time it
-function test(s,f)
-	N=0
-	local c=os.clock()
-	local v=f(n)
-	local t=os.clock()-c
-	print(s,n,v,t,N)
-end
-
-n=arg[1] or 24		-- for other values, do lua fib.lua XX
-n=tonumber(n)
-print("","n","value","time","evals")
-test("plain",fib)
-fib=cache(fib)
-test("cached",fib)
diff --git a/test/fibfor.lua b/test/fibfor.lua
deleted file mode 100644
index 8bbba39..0000000
--- a/test/fibfor.lua
+++ /dev/null
@@ -1,13 +0,0 @@
--- example of for with generator functions
-
-function generatefib (n)
-  return coroutine.wrap(function ()
-    local a,b = 1, 1
-    while a <= n do
-      coroutine.yield(a)
-      a, b = b, a+b
-    end
-  end)
-end
-
-for i in generatefib(1000) do print(i) end
diff --git a/test/globals.lua b/test/globals.lua
deleted file mode 100644
index d4c20e1..0000000
--- a/test/globals.lua
+++ /dev/null
@@ -1,13 +0,0 @@
--- reads luac listings and reports global variable usage
--- lines where a global is written to are marked with "*"
--- typical usage: luac -p -l file.lua | lua globals.lua | sort | lua table.lua
-
-while 1 do
- local s=io.read()
- if s==nil then break end
- local ok,_,l,op,g=string.find(s,"%[%-?(%d*)%]%s*([GS])ETGLOBAL.-;%s+(.*)$")
- if ok then
-  if op=="S" then op="*" else op="" end
-  io.write(g,"\t",l,op,"\n")
- end
-end
diff --git a/test/hello.lua b/test/hello.lua
deleted file mode 100644
index 0925498..0000000
--- a/test/hello.lua
+++ /dev/null
@@ -1,3 +0,0 @@
--- the first program in every language
-
-io.write("Hello world, from ",_VERSION,"!\n")
diff --git a/test/life.lua b/test/life.lua
deleted file mode 100644
index 911d9fe..0000000
--- a/test/life.lua
+++ /dev/null
@@ -1,111 +0,0 @@
--- life.lua
--- original by Dave Bollinger <DBollinger@compuserve.com> posted to lua-l
--- modified to use ANSI terminal escape sequences
--- modified to use for instead of while
-
-local write=io.write
-
-ALIVE="¥"	DEAD="þ"
-ALIVE="O"	DEAD="-"
-
-function delay() -- NOTE: SYSTEM-DEPENDENT, adjust as necessary
-  for i=1,10000 do end
-  -- local i=os.clock()+1 while(os.clock()<i) do end
-end
-
-function ARRAY2D(w,h)
-  local t = {w=w,h=h}
-  for y=1,h do
-    t[y] = {}
-    for x=1,w do
-      t[y][x]=0
-    end
-  end
-  return t
-end
-
-_CELLS = {}
-
--- give birth to a "shape" within the cell array
-function _CELLS:spawn(shape,left,top)
-  for y=0,shape.h-1 do
-    for x=0,shape.w-1 do
-      self[top+y][left+x] = shape[y*shape.w+x+1]
-    end
-  end
-end
-
--- run the CA and produce the next generation
-function _CELLS:evolve(next)
-  local ym1,y,yp1,yi=self.h-1,self.h,1,self.h
-  while yi > 0 do
-    local xm1,x,xp1,xi=self.w-1,self.w,1,self.w
-    while xi > 0 do
-      local sum = self[ym1][xm1] + self[ym1][x] + self[ym1][xp1] +
-                  self[y][xm1] + self[y][xp1] +
-                  self[yp1][xm1] + self[yp1][x] + self[yp1][xp1]
-      next[y][x] = ((sum==2) and self[y][x]) or ((sum==3) and 1) or 0
-      xm1,x,xp1,xi = x,xp1,xp1+1,xi-1
-    end
-    ym1,y,yp1,yi = y,yp1,yp1+1,yi-1
-  end
-end
-
--- output the array to screen
-function _CELLS:draw()
-  local out="" -- accumulate to reduce flicker
-  for y=1,self.h do
-   for x=1,self.w do
-      out=out..(((self[y][x]>0) and ALIVE) or DEAD)
-    end
-    out=out.."\n"
-  end
-  write(out)
-end
-
--- constructor
-function CELLS(w,h)
-  local c = ARRAY2D(w,h)
-  c.spawn = _CELLS.spawn
-  c.evolve = _CELLS.evolve
-  c.draw = _CELLS.draw
-  return c
-end
-
---
--- shapes suitable for use with spawn() above
---
-HEART = { 1,0,1,1,0,1,1,1,1; w=3,h=3 }
-GLIDER = { 0,0,1,1,0,1,0,1,1; w=3,h=3 }
-EXPLODE = { 0,1,0,1,1,1,1,0,1,0,1,0; w=3,h=4 }
-FISH = { 0,1,1,1,1,1,0,0,0,1,0,0,0,0,1,1,0,0,1,0; w=5,h=4 }
-BUTTERFLY = { 1,0,0,0,1,0,1,1,1,0,1,0,0,0,1,1,0,1,0,1,1,0,0,0,1; w=5,h=5 }
-
--- the main routine
-function LIFE(w,h)
-  -- create two arrays
-  local thisgen = CELLS(w,h)
-  local nextgen = CELLS(w,h)
-
-  -- create some life
-  -- about 1000 generations of fun, then a glider steady-state
-  thisgen:spawn(GLIDER,5,4)
-  thisgen:spawn(EXPLODE,25,10)
-  thisgen:spawn(FISH,4,12)
-
-  -- run until break
-  local gen=1
-  write("\027[2J")	-- ANSI clear screen
-  while 1 do
-    thisgen:evolve(nextgen)
-    thisgen,nextgen = nextgen,thisgen
-    write("\027[H")	-- ANSI home cursor
-    thisgen:draw()
-    write("Life - generation ",gen,"\n")
-    gen=gen+1
-    if gen>2000 then break end
-    --delay()		-- no delay
-  end
-end
-
-LIFE(40,20)
diff --git a/test/luac.lua b/test/luac.lua
deleted file mode 100644
index 96a0a97..0000000
--- a/test/luac.lua
+++ /dev/null
@@ -1,7 +0,0 @@
--- bare-bones luac in Lua
--- usage: lua luac.lua file.lua
-
-assert(arg[1]~=nil and arg[2]==nil,"usage: lua luac.lua file.lua")
-f=assert(io.open("luac.out","wb"))
-assert(f:write(string.dump(assert(loadfile(arg[1])))))
-assert(f:close())
diff --git a/test/printf.lua b/test/printf.lua
deleted file mode 100644
index 58c63ff..0000000
--- a/test/printf.lua
+++ /dev/null
@@ -1,7 +0,0 @@
--- an implementation of printf
-
-function printf(...)
- io.write(string.format(...))
-end
-
-printf("Hello %s from %s on %s\n",os.getenv"USER" or "there",_VERSION,os.date())
diff --git a/test/readonly.lua b/test/readonly.lua
deleted file mode 100644
index 85c0b4e..0000000
--- a/test/readonly.lua
+++ /dev/null
@@ -1,12 +0,0 @@
--- make global variables readonly
-
-local f=function (t,i) error("cannot redefine global variable `"..i.."'",2) end
-local g={}
-local G=getfenv()
-setmetatable(g,{__index=G,__newindex=f})
-setfenv(1,g)
-
--- an example
-rawset(g,"x",3)
-x=2
-y=1	-- cannot redefine `y'
diff --git a/test/sieve.lua b/test/sieve.lua
deleted file mode 100644
index 0871bb2..0000000
--- a/test/sieve.lua
+++ /dev/null
@@ -1,29 +0,0 @@
--- the sieve of of Eratosthenes programmed with coroutines
--- typical usage: lua -e N=1000 sieve.lua | column
-
--- generate all the numbers from 2 to n
-function gen (n)
-  return coroutine.wrap(function ()
-    for i=2,n do coroutine.yield(i) end
-  end)
-end
-
--- filter the numbers generated by `g', removing multiples of `p'
-function filter (p, g)
-  return coroutine.wrap(function ()
-    while 1 do
-      local n = g()
-      if n == nil then return end
-      if math.mod(n, p) ~= 0 then coroutine.yield(n) end
-    end
-  end)
-end
-
-N=N or 1000		-- from command line
-x = gen(N)		-- generate primes up to N
-while 1 do
-  local n = x()		-- pick a number until done
-  if n == nil then break end
-  print(n)		-- must be a prime number
-  x = filter(n, x)	-- now remove its multiples
-end
diff --git a/test/sort.lua b/test/sort.lua
deleted file mode 100644
index 0bcb15f..0000000
--- a/test/sort.lua
+++ /dev/null
@@ -1,66 +0,0 @@
--- two implementations of a sort function
--- this is an example only. Lua has now a built-in function "sort"
-
--- extracted from Programming Pearls, page 110
-function qsort(x,l,u,f)
- if l<u then
-  local m=math.random(u-(l-1))+l-1	-- choose a random pivot in range l..u
-  x[l],x[m]=x[m],x[l]			-- swap pivot to first position
-  local t=x[l]				-- pivot value
-  m=l
-  local i=l+1
-  while i<=u do
-    -- invariant: x[l+1..m] < t <= x[m+1..i-1]
-    if f(x[i],t) then
-      m=m+1
-      x[m],x[i]=x[i],x[m]		-- swap x[i] and x[m]
-    end
-    i=i+1
-  end
-  x[l],x[m]=x[m],x[l]			-- swap pivot to a valid place
-  -- x[l+1..m-1] < x[m] <= x[m+1..u]
-  qsort(x,l,m-1,f)
-  qsort(x,m+1,u,f)
- end
-end
-
-function selectionsort(x,n,f)
- local i=1
- while i<=n do
-  local m,j=i,i+1
-  while j<=n do
-   if f(x[j],x[m]) then m=j end
-   j=j+1
-  end
- x[i],x[m]=x[m],x[i]			-- swap x[i] and x[m]
- i=i+1
- end
-end
-
-function show(m,x)
- io.write(m,"\n\t")
- local i=1
- while x[i] do
-  io.write(x[i])
-  i=i+1
-  if x[i] then io.write(",") end
- end
- io.write("\n")
-end
-
-function testsorts(x)
- local n=1
- while x[n] do n=n+1 end; n=n-1		-- count elements
- show("original",x)
- qsort(x,1,n,function (x,y) return x<y end)
- show("after quicksort",x)
- selectionsort(x,n,function (x,y) return x>y end)
- show("after reverse selection sort",x)
- qsort(x,1,n,function (x,y) return x<y end)
- show("after quicksort again",x)
-end
-
--- array to be sorted
-x={"Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"}
-
-testsorts(x)
diff --git a/test/table.lua b/test/table.lua
deleted file mode 100644
index 235089c..0000000
--- a/test/table.lua
+++ /dev/null
@@ -1,12 +0,0 @@
--- make table, grouping all data for the same item
--- input is 2 columns (item, data)
-
-local A
-while 1 do
- local l=io.read()
- if l==nil then break end
- local _,_,a,b=string.find(l,'"?([_%w]+)"?%s*(.*)$')
- if a~=A then A=a io.write("\n",a,":") end
- io.write(" ",b)
-end
-io.write("\n")
diff --git a/test/trace-calls.lua b/test/trace-calls.lua
deleted file mode 100644
index 6d7a7b3..0000000
--- a/test/trace-calls.lua
+++ /dev/null
@@ -1,32 +0,0 @@
--- trace calls
--- example: lua -ltrace-calls bisect.lua
-
-local level=0
-
-local function hook(event)
- local t=debug.getinfo(3)
- io.write(level," >>> ",string.rep(" ",level))
- if t~=nil and t.currentline>=0 then io.write(t.short_src,":",t.currentline," ") end
- t=debug.getinfo(2)
- if event=="call" then
-  level=level+1
- else
-  level=level-1 if level<0 then level=0 end
- end
- if t.what=="main" then
-  if event=="call" then
-   io.write("begin ",t.short_src)
-  else
-   io.write("end ",t.short_src)
-  end
- elseif t.what=="Lua" then
--- table.foreach(t,print)
-  io.write(event," ",t.name or "(Lua)"," <",t.linedefined,":",t.short_src,">")
- else
- io.write(event," ",t.name or "(C)"," [",t.what,"] ")
- end
- io.write("\n")
-end
-
-debug.sethook(hook,"cr")
-level=0
diff --git a/test/trace-globals.lua b/test/trace-globals.lua
deleted file mode 100644
index 295e670..0000000
--- a/test/trace-globals.lua
+++ /dev/null
@@ -1,38 +0,0 @@
--- trace assigments to global variables
-
-do
- -- a tostring that quotes strings. note the use of the original tostring.
- local _tostring=tostring
- local tostring=function(a)
-  if type(a)=="string" then
-   return string.format("%q",a)
-  else
-   return _tostring(a)
-  end
- end
-
- local log=function (name,old,new)
-  local t=debug.getinfo(3,"Sl")
-  local line=t.currentline
-  io.write(t.short_src)
-  if line>=0 then io.write(":",line) end
-  io.write(": ",name," is now ",tostring(new)," (was ",tostring(old),")","\n")
- end
-
- local g={}
- local set=function (t,name,value)
-  log(name,g[name],value)
-  g[name]=value
- end
- setmetatable(getfenv(),{__index=g,__newindex=set})
-end
-
--- an example
-
-a=1
-b=2
-a=10
-b=20
-b=nil
-b=200
-print(a,b,c)
diff --git a/test/xd.lua b/test/xd.lua
deleted file mode 100644
index ebc3eff..0000000
--- a/test/xd.lua
+++ /dev/null
@@ -1,14 +0,0 @@
--- hex dump
--- usage: lua xd.lua < file
-
-local offset=0
-while true do
- local s=io.read(16)
- if s==nil then return end
- io.write(string.format("%08X  ",offset))
- string.gsub(s,"(.)",
-	function (c) io.write(string.format("%02X ",string.byte(c))) end)
- io.write(string.rep(" ",3*(16-string.len(s))))
- io.write(" ",string.gsub(s,"%c","."),"\n") 
- offset=offset+16
-end