Cheap Callback Pass 1

gistfile1.rb

module Actions
  module Base
      def email(args)
	extend(Mail)
	send(*args)
      end
      def statistics(m,*args)
	extend(Statistics)
	send(m,*args)
      end
   end
   module Mail
      def complete(args)
	puts "complete mail"
      end

      def auto_posted
	puts "posted"
      end
    end
    module Statistics
      def complete(args)
	puts "complete stats"
      end

      def posted(args)
	puts "posted #{args}"
      end
    end
end


module Events
   attr_accessor :wrapper

   def self.extended(base)
	base.wrapper = {}
	base.send(:include,Triggers)
   end

  def completed_trip(&block)
    wrapper[:completed_trip] = block 
  end
  def auto_posted(&block)
    wrapper[:auto_posted] = block
  end
end

module Triggers
   def auto_posted!
	current_wrapper = self.class.wrapper[:auto_posted]
	send(:extend, Actions::Base)
	current_wrapper.call(self)
    end
   def completed_trip!
	current_wrapper = self.class.wrapper[:completed_trip]
	send(:extend, Actions::Base)
	current_wrapper.call(self)
    end
end

module CallbackChain
   def notification_callbacks(&block)
	send(:extend, Events)
        instance_eval(&block)
   end
end

class A
  extend CallbackChain

  notification_callbacks do
     completed_trip do |d|
	d.email :complete
	d.statistics :complete, 2
     end
     auto_posted do |d|
	d.email :auto_posted
	d.statistics :posted, 1
     end
   end
 end


A.new.completed_trip!