achr3f/rufus-lua

embedding Lua in Ruby, via FFI

rufus-lua¶ ↑

Lua embedded in Ruby, via Ruby FFI

Lua¶ ↑

www.lua.org/about.html says :

“”“ Lua is a powerful, fast, lightweight, embeddable scripting language.

Lua combines simple procedural syntax with powerful data description constructs based on associative arrays and extensible semantics. Lua is dynamically typed, runs by interpreting bytecode for a register-based virtual machine, and has automatic memory management with incremental garbage collection, making it ideal for configuration, scripting, and rapid prototyping. “”“

www.lua.org/

other Ruby and Lua bridges / connectors¶ ↑

rubyluabridge.rubyforge.org/ raa.ruby-lang.org/project/ruby-lua rubydoc.info/gems/rlua/1.0/frames

using rufus-lua¶ ↑

If you don’t have liblua.dylib on your system, scroll until “compiling liblua.dylib” to learn how to get it.

sudo gem install rufus-lua

then

require 'rubygems'
require 'rufus/lua'

s = Rufus::Lua::State.new

puts s.eval("return table.concat({ 'hello', 'from', 'Lua' }, ' ')")
  #
  # => "Hello from Lua"

s.close

binding Ruby code as Lua functions¶ ↑

require 'rubygems'
require 'rufus/lua'

s = Rufus::Lua::State.new

s.function 'key_up' do |table|
  table.inject({}) do |h, (k, v)|
    h[k.to_s.upcase] = v
  end
end

p s.eval(%{
  local table = { CoW = 2, pigs = 3, DUCKS = 'none' }
  return key_up(table) -- calling Ruby from Lua...
}).to_h
  # => { 'COW' => 2.0, 'DUCKS => 'none', 'PIGS' => 3.0 }

s.close

It’s OK to bind a function inside of a table (library) :

require 'rubygems'
require 'rufus/lua'

s = Rufus::Lua::State.new

s.eval("rubies = {}")
s.function 'add' do |x, y|
  x + y
end

s.eval("rubies.add(1, 2)")
  # => 3.0

s.close

You can omit the table definition (only 1 level allowed here though) :

require 'rubygems'
require 'rufus/lua'

s = Rufus::Lua::State.new

s.function 'rubies.add' do |x, y|
  x + y
end

s.eval("rubies.add(1, 2)")
  # => 3.0

s.close

The specs contain more examples :

github.com/jmettraux/rufus-lua/tree/master/spec/

rufus-lua’s rdoc is at :

rufus.rubyforge.org/rufus-lua/

compiling liblua.dylib¶ ↑

original instructions by Adrian Perez at :

lua-users.org/lists/lua-l/2006-09/msg00894.html

get the source at

www.lua.org/ftp/lua-5.1.4.tar.gz

then

tar xzvf lua-5.1.4.tar.gz
cd lua-5.1.4

modify the file src/Makefile as per lua-users.org/lists/lua-l/2006-09/msg00894.html

make 
make macosx # or make linux ...
make -C src liblua.dylib
sudo cp src/liblua.dylib /usr/local/lib/

sudo make macosx install

build dependencies¶ ↑

The following gems are needed to run the specs

sudo gem install bacon

tested with¶ ↑

ruby 1.8.7p72, ruby 1.9.1p0, jruby 1.2.0 jruby 1.1.6 has an issue with errors raised inside of Ruby functions (callbacks)

ruby-ffi 0.4.0 and 0.5.0

dependencies¶ ↑

the ruby gem ‘ffi’

mailing list¶ ↑

On the rufus-ruby list :

groups.google.com/group/rufus-ruby

issue tracker¶ ↑

github.com/jmettraux/rufus-lua/issues

irc¶ ↑

irc.freenode.net #ruote

source¶ ↑

github.com/jmettraux/rufus-lua

git clone git://github.com/jmettraux/rufus-lua.git

credits¶ ↑

many thanks to the authors of Ruby FFI, and of Lua

wiki.github.com/ffi/ffi lua.org/

authors¶ ↑

John Mettraux, [email protected], jmettraux.wordpress.com Alain Hoang, blogs.law.harvard.edu/hoanga/ Scott Persinger, github.com/scottpersinger/

the rest of Rufus¶ ↑

rufus.rubyforge.org

license¶ ↑

MIT

Lua itself is licensed under the MIT license as well :

www.lua.org/license.html