From: Ola Bini <ola.bini@...>
Date: 2006-08-29T17:02:10+09:00
Subject: Including a class.

Hi,

As an extension on my earlier question of partial includes; I just 
noticed that you can't include a Class, even though it is a Module.

Anyone have a way of doing this?

What I would like to do, is to be able to dynamically mix in some good 
methods from preexisting classes, depending on arguments to the 
constructor. Since I need to do it dynamically, and also need it 
differently for different instances of the class, I can't make it 
inherit the other class.

What I would like is something like this; say I have class Foo and Bar, 
with many methods in them.

class Baz < AnotherAbstractBaseClass
   def initialize(config={})
     self.singleton_class.module_eval do
       if config[:foo]
         partial_include Foo, :method1, :method7
       elsif config[:bar]
         partial_include Bar, :method1, :method7
       end
     end
   end
end

Baz.new(:bar => true).method1


But I can't have an instance of Bar or Foo so delegating is impossible. 
I need the methods to be in the the same instance. Any help? =)

-- 
  Ola Bini (http://ola-bini.blogspot.com)
  JvYAML, RbYAML, JRuby and Jatha contributor
  System Developer, Karolinska Institutet (http://www.ki.se)
  OLogix Consulting (http://www.ologix.com)

  "Yields falsehood when quined" yields falsehood when quined.