From: Gavin Kistner <gavin.kistner@...>
Date: 2006-12-19T01:45:55+09:00
Subject: Re: item order in Object#methods

From: Andrea Fazzi [mailto:andrea.fazzi@alca.le.it] 
> Rob Biedenharn wrote:
> > If it's important, why not sort them first:
> >    self.methods.sort.collect { ... }
> 
> Because I'm interested to the methods' definition order 
> inside the class 
> not to the alphabetical order of methods' name. The names init_1, 
> init_2, etc. were just an example.

I'm moderately sure that Ruby doesn't internally keep track of the order
in which classes were defined, or the order in which methods are added
to them. But that doesn't mean you can't do it yourself with a little
bit of work.

#track_methods.rb
class Module
  def track_methods
    @methods_in_order = []
    class << self
      attr_reader :methods_in_order
      def method_added( method_name )
        @methods_in_order << method_name
      end
    end
  end
end



# init.rb
module Foo
  def init
    self.class.methods_in_order.each do |init_meth|
      unless init_meth==:initialize
        self.send( init_meth )
      end
    end
  end
end

class Bar
  include Foo
  track_methods
  def initialize
    init
  end
  def init_1; puts "Calling init_1!"; end
end

class Bar
  def init_2; puts "Calling init_2!"; end
  def init_3; puts "Calling init_3!"; end
  def init_4; puts "Calling init_4!"; end
end


#init_2.rb
require 'track_methods'
require 'init'
class Bar
  def init_5; puts "Calling init_5!"; end
  def init_6; puts "Calling init_6!"; end
end

Bar.new
#=> Calling init_1!
#=> Calling init_2!
#=> Calling init_3!
#=> Calling init_4!
#=> Calling init_5!
#=> Calling init_6!