From: dblack@...
Date: 2005-12-29T11:03:54+09:00
Subject: Re: get mixin's name

Hi --

On Thu, 29 Dec 2005, Payton Swick wrote:

> A somewhat weird situation.
>
> I have a module which I include in a class using Module#extend.  That module 
> defines an instance method which returns the name of the module that defined 
> the method.  Currently, I do that by hard-coding the string into the method 
> definition, but it seems that there should really be a better way.
>
> Here's some code:
>
> irb(main):001:0> module Awesome
> irb(main):002:1> def who_am_i
> irb(main):003:2> 'Awesome' # Repeating myself, bad!
> irb(main):004:2> end
> irb(main):005:1> end
> => nil
> irb(main):006:0> class One
> irb(main):007:1> def initialize(what)
> irb(main):008:2> extend what
> irb(main):009:2> end
> irb(main):010:1> end
> => nil
> irb(main):011:0> a = One.new(Awesome)
> => #<One:0x40322710>
> irb(main):012:0> a.who_am_i
> => "Awesome"

Does this help?

   module Awesome
     s = self
     define_method("who_am_i") { s }
   end

   obj = Object.new
   obj.extend(Awesome)
   p obj.who_am_i  # Awesome

There's a bit of semantic weirdness in the object claiming to be the
module :-)  But anyway, that's one way to get the module object into
one of its own instance methods.


David

-- 
David A. Black
dblack@wobblini.net

"Ruby for Rails", from Manning Publications, coming April 2006!
http://www.manning.com/books/black