From: "T. Onoma" <transami@...>
Date: 2003-12-17T04:16:32+09:00
Subject: Re: Copying methods from one class to another

On Tuesday 16 December 2003 07:32 pm, David A. Black wrote:
> > class C
> >   # don't even need the def here
> > end
> >
> > class C < C;
> >   @__aspect__ = true
> >   def self.method_added(m)
> >     meth = self.instance_method(m)
> >     self.superclass.class_eval %Q{
> >       remove_method(:#{m}) if method_defined?(:m)
> >       define_method(:#{m}, meth)
> >     }
> >     self.remove_method(m)
> >   end
> > end
> >
> > class C  # this is what I forgot: to add a method
> >   def x
> >     print "<"; super
> >   end
> > end
> >
> > c = C.new
> > c.x
>
> That code gives me:
>
> redef.rb:5: warning: already initialized constant C
> redef.rb:13:in `method_added': private method `remove_method' called
> for C:Class (NoMethodError)
>         from redef.rb:18

Agghhh...I sware I ran it before I posted it, hmm.... oh, duh! I added the 
self on remove_method. (Note to self: DO NOT touch up code for email posts 
after putting them in email message!)  Here, I promise this one "works" and 
is more concise thanks to some other posts I was able to learn from.

  class C
  end

  class C < C;
    def self.method_added(m)
      meth = self.instance_method(m)
      self.superclass.__send__(:define_method, m, meth)
      self.__send__(:remove_method, m)
    end
  end

  class C
    def x
      print "<"; super
    end
  end

  c = C.new
  c.x


-- 
T.