From: "Jesús Gabriel y Galán" <jgabrielygalan@...>
Date: 2011-04-15T16:45:35+09:00
Subject: Re: looking for an "inversion" pattern

On Fri, Apr 15, 2011 at 7:16 AM, Fearless Fool <r@alum.mit.edu> wrote:
> I'm sure there's a clean way to do this in Ruby, but I haven't figured
> it out.
>
> I'd like to create a method +foo+ that transforms:
>
>   my_obj.foo.some_method(*args)
>
> to
>
>  MyClass.some_method(my_obj, *args)
>
> Maybe I'm overthinking this.  I'll keep working on this, but in the
> meantime, I'm open to suggestions.

I would create a method foo that returns a proxy that remembers which
was the original receiver. This proxy can have a method_missing
implementation that calls MyClass.xxxx passing the original receiver
and all params. For example:

ruby-1.8.7-p334 :003 > class Proxy
ruby-1.8.7-p334 :004?>   def initialize target
ruby-1.8.7-p334 :005?>     @target = target
ruby-1.8.7-p334 :006?>     end
ruby-1.8.7-p334 :007?>   def method_missing meth, *args, &blk
ruby-1.8.7-p334 :008?>     MyClass.send(meth,@target,*args,&blk)
ruby-1.8.7-p334 :009?>     end
ruby-1.8.7-p334 :010?>   end
 => nil
ruby-1.8.7-p334 :011 > class Something
ruby-1.8.7-p334 :012?>   def foo
ruby-1.8.7-p334 :013?>     Proxy.new self
ruby-1.8.7-p334 :014?>     end
ruby-1.8.7-p334 :015?>   end
 => nil
ruby-1.8.7-p334 :016 > class MyClass
ruby-1.8.7-p334 :017?>   def self.test1 obj, *args
ruby-1.8.7-p334 :018?>     p [obj,*args]
ruby-1.8.7-p334 :019?>     end
ruby-1.8.7-p334 :020?>   end
 => nil
ruby-1.8.7-p334 :021 > my_obj = Something.new
 => #<Something:0xb72c8514>
ruby-1.8.7-p334 :022 > my_obj.foo.test1 1,2,3
[#<Something:0xb72c8514>, 1, 2, 3]

I don't know if method foo is part of your class, or maybe you can
build a method and extend the required objects with it.

Jesus.