Updating event fire method to fire event on the @piece. This Gist is for https://github.com/nathankleyn/ruby_events/issues/3.

ruby-events testing

#!/usr/bin/ruby
# coding: utf-8

# author : Marc Quinton, march 2013, licence : http://fr.wikipedia.org/wiki/WTFPL

libdir = 'lib'
$LOAD_PATH.unshift(libdir) unless $LOAD_PATH.include?(libdir)


require 'pp'
require 'rubygems'

# https://github.com/nathankleyn/ruby_events
require 'ruby_events'

case ARGV[0]

when 'simple'
   events.listen(:bling) do |event_data|
      puts 'bling event triggered ; event data = ' + event_data
   end
   events.fire(:bling, "hello world")

when 'classes'

   class Piece
      def initialize
         puts "Piece.initialize"
         self.events.listen(:move) do |event_data|
            puts "Piece.moved " + event_data
         end
         
         self.events.fire(:move, 'from Piece')
      end
   end

   class Puzzle
      def initialize
         @piece = Piece.new
      end
      
      def move
         # send ":move" signal any thing  object listening to :move signal
         @piece.events.fire(:move)
      end
   end

   puzzle=Puzzle.new
   puzzle.move

end