= Description RLua is Ruby to Lua bindings library that features nearly complete coverage of Lua C API, seamless translation of Lua and Ruby objects into each other, calling Lua functions from Ruby and vice versa.

RLua currently uses Lua 5.4, and is Ruby 1.9+ compatible.

= Installation RLua is distributed as gem package through rubygems.org, so the procedure is quite usual. It uses native Lua C API, so it will need to compile an extension during installation.

On Linux, you will need to install Lua development files first. They are packaged as <tt>liblua5.4-dev</tt> in Debian and it's derivatives (like Ubuntu). After that you can simply run <tt>gem install rlua</tt>.

On Windows, you will need MSVC to compile everything. Through I did not tested this (and so cannot provide a detailed description), it should work fine.

= Example code

require 'rlua'

state = Lua::State.new # create Lua interpreter state.__load_stdlib :all # load some standard libraries in it state.__eval "print('hello, world')" # launch some Lua code

state.value = 10 # set a variable in Ruby state.__eval "print(value)" # show it's value from Lua

state.__eval "value = 15" # set a variable in Lua p state.value # show it's value from Ruby

create a function in Lua

state.__eval "function lua_func() print('hello from Lua') end"

launch it from Ruby

state.lua_func

create a table in Ruby and method in it

state.ruby = { 'meaning_of_life' => 42, 'zaphod' => lambda { |this| p "Meaning of life: #{this.meaning_of_life}" } }

launch that from Lua as instance method

state.__eval "ruby:zaphod()"

= Type conversion Lua and Ruby types are seamlessly translated into each other when calling functions, changing tables and so on. The translation is conservative: you can convert a value from Ruby to Lua, then backwards and will always receive an object that will behave absolutely the same.

Here is a table of type mapping: <b>Ruby type</b>:: <b>Lua type</b> nil:: nil Boolean (TrueClass or FalseClass):: true or false Fixnum, Bignum or Float:: number Proc:: function String:: string Hash:: table Array:: table (with numeric keys)

Hashes and Arrays are translated recursively: all keys and values are translated too. Getting any Lua function to Ruby code (even the Ruby proc that was translated before) results in Lua::Function created, and tables behave the same creating Lua::Table object.

Proc objects are duck-typed: anything that responds to +call+ method is considered Proc.

Translation of any object not in the list is impossible and will generate an TypeError exception.

= Notes Most functions are named much like their C API counterparts.

'Ruby-object-like' table indexing convention is described in Lua::Table, and function calling is described in Lua::Function.

Everything not currently implemented is described in {TODO list}[link:files/TODO_rdoc.html].

= Author RLua is currently developed solely by whitequark (whitequark@whitequark.org[mailto:whitequark@whitequark.org]). Feel free to email me if you encounter any bugs.

= License This program is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with this program. If not, see http://www.gnu.org/licenses/.