From: Trans <transfire@...>
Date: 2007-08-03T12:00:25+09:00
Subject: Re: From method redefinition to classless Ruby.



On Aug 2, 4:43 pm, "Robert Dober" <robert.do...@gmail.com> wrote:
> Hi list
>
> Ara's post about method redefinition was extremely rich intellectual
> food, took some time to digest, but I just thought I share my findings
> with you.

Ara and Pit are impressive meta-coders indeed. Think Ara might even
have a Prototype lib
you'd enjoy.

BTW, if we were all good little scouts and always modularized our code
one could use:

  class Module
    # Prepend an "aspect" module to a module.
    #
    #   module X
    #     def x; "x"; end
    #   end
    #
    #   module U
    #     def x; '{' + super + '}'; end
    #   end
    #
    #   X.prepend U
    #
    #   X.x  # => "{x}"

    def prepend( aspect )
      aspect.send(:include, self)
      extend aspect
    end
  end

Another trick for common injuns:

  class Class

    # Prepend an "aspect" module to a class.
    #
    # class Firetruck
    #   def put_out_fire(option)
    #     "Put out #{option}"
    #   end
    # end
    #
    # module FastFiretruck
    #   def put_out_fire(option)
    #     super("very #{option}!")
    #   end
    # end
    #
    # Firetruck.prepend(FastFiretruck)
    #
    # ft = Firetruck.new
    # ft.put_out_fire('fast') #=> "Put out very fast!"

    def prepend( aspect )
      _new      = method(:new)
      _allocate = method(:allocate)
      (class << self; self; end).class_eval do
        define_method(:new) do |*args|
          o = _new.call(*args)
          o.extend aspect
          o
        end
        define_method(:allocate) do |*args|
          o = _allocate.call(*args)
          o.extend aspect
          o
        end
      end
    end

  end

Albeit that has some unfortunate shortcomings.

T.