From: transfire@...
Date: 2006-07-14T14:17:39+09:00
Subject: Re: Preferred monkeypatching technique


Daniel DeLorme wrote:
> Tom Werner wrote:
> > Allow me to present a scenario:
> >
> > class Firetruck
> >    def put_out_fire(options = {})
> >       # code
> >    end
> > end
>
> Here's what I'd do to keep it clean:
>
> module FastFiretruck
>    def initialize(*args)
>      super
>      self.extend FastFiretruck::Obj
>    end
>    module Obj
>      def put_out_fire(options = {})
>        super({:fast => "please!"}.merge(options))
>      end
>    end
> end
> Firetruck.class_eval{ include FastFiretruck }

Hey, thanks Daniel! You actaully led me to a new potential approach.
Here, try this:


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

# EXAMPLE

class Firetruck
   def put_out_fire(options = {})
     "put out #{options}"
   end
end

module FastFiretruck

  def put_out_fire(options = {})
    super({:fast => "please!"}.merge(options))
  end
end

Firetruck.monkey_patch(FastFiretruck)

ft = Firetruck.new
p ft.put_out_fire


T.