                             Lua Welcome to Lua 5.4

   about · installation · changes · license · reference manual

About Lua

   Lua is a powerful, efficient, lightweight, embeddable scripting language
   developed by a team at PUC-Rio, the Pontifical Catholic University of Rio
   de Janeiro in Brazil. Lua is free software used in many products and
   projects around the world.

   Lua's official web site provides complete information about Lua, including
   an executive summary and updated documentation, especially the reference
   manual, which may differ slightly from the local copy distributed in this
   package.

Installing Lua

   Lua is distributed in source 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, such as Linux and Mac
   OS X. See also instructions for other systems and customization options.

   If you don't have the time or the inclination to compile Lua yourself, get
   a binary from LuaBinaries. Try also LuaDist, a multi-platform distribution
   of Lua that includes batteries.

  Building Lua

   In most common Unix-like platforms, simply do "make". Here are the
   details.
    1. Open a terminal window and move to the top-level directory, which is
       named lua-5.4.4. The Makefile there controls both the build process
       and the installation process.

    2. Do "make". The Makefile will guess your platform and build Lua for it.

    3. If the guess failed, do "make help" and see if your platform is
       listed. The platforms currently supported are:

       guess aix bsd c89 freebsd generic linux linux-readline macosx mingw
       posix solaris

       If your platform is listed, just do "make xxx", where xxx is your
       platform name.

       If your platform is not listed, try the closest one or posix, generic,
       c89, in this order.

    4. 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).

    5. To check that Lua has been built correctly, do "make test" after
       building Lua. This will run the interpreter and print its version.

   If you're running Linux, try "make linux-readline" to build the
   interactive Lua interpreter with handy line-editing and history
   capabilities. If you get compilation errors, make sure you have installed
   the readline development package (which is probably named libreadline-dev
   or readline-devel). If you get link errors after that, then try "make
   linux-readline MYLIBS=-ltermcap".

  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 the Makefile. You'll probably need
   the right permissions to install files, and so may need to do "sudo make
   install".

   To build and install Lua in one step, do "make all install", or "make xxx
   install", where xxx is your platform name.

   To install Lua locally after building it, do "make local". This will
   create a directory install with subdirectories bin, include, lib, man,
   share, and install Lua as listed below. To install Lua locally, but in
   some other directory, do "make install INSTALL_TOP=xxx", where xxx is your
   chosen directory. The installation starts in the src and doc directories,
   so take care if INSTALL_TOP is not an absolute path.

   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. 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.

  Customization

   Three kinds of 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 in the command line when invoking make. Nevertheless,
   it's probably best to edit and save the Makefiles to record the changes
   you've made.

   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.

  Building Lua on 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 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
           lcorolib.c ldblib.c liolib.c lmathlib.c loadlib.c loslib.c
           lstrlib.c ltablib.c lutf8lib.c linit.c

   interpreter:
           library, lua.c

   compiler:
           library, luac.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. 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 — but don't 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. In all cases, the compiler luac should be
   linked statically.

   As mentioned above, you may edit src/luaconf.h to customize some features
   before building Lua.

Changes since Lua 5.3

   Here are the main changes introduced in Lua 5.4. The reference manual
   lists the incompatibilities that had to be introduced.

  Main changes

     * new generational mode for garbage collection
     * to-be-closed variables
     * const variables
     * userdata can have multiple user values
     * new implementation for math.random
     * warning system
     * debug information about function arguments and returns
     * new semantics for the integer 'for' loop
     * optional 'init' argument to 'string.gmatch'
     * new functions 'lua_resetthread' and 'coroutine.close'
     * string-to-number coercions moved to the string library
     * allocation function allowed to fail when shrinking a memory block
     * new format '%p' in 'string.format'
     * utf8 library accepts codepoints up to 2^31

License

   [osi certified] Lua is free software distributed under the terms of the
   MIT license 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 this.

     Copyright © 1994–2022 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.

   Last update: Mon Jan 3 09:54:18 UTC 2022
