From: Sean O'Halpin <sean.ohalpin@...>
Date: 2006-07-13T21:47:37+09:00
Subject: Re: re-define class method

On 7/13/06, David Chelimsky <david@objectmentor.com> wrote:
> On Jul 13, 2006, at 5:33 AM, dblack@wobblini.net wrote:
>
> > On Thu, 13 Jul 2006, David Chelimsky wrote:
> >
> >> thing_singleton_class = class << Thing; self; end
> >> thing_singleton_class.send(:define_method, :class_method, proc
> >> { "replaced" })
> >>
> >> Thing.class_method
> >> => "replaced"
> >
> > Don't forget that you can do this much more concisely (unless you have
> > a specific need to go the long way round):
> >
> >   def Thing.class_method
> >     "replaced"
> >   end
>
> Thanks David. I definitely appreciate the conciseness of this, and
> will use that when I know the type. The problem I'm working on
> requires a solution to replacing singleton methods on arbitrary types
> at runtime, so I think I have to stick w/ the more cryptic version.
> Unless you have a different suggestion - I'm just getting my head
> wrapped around metaprogramming and singleton classes, so all
> suggestions are most welcome.
>
> Thanks,
> David
>

You can use David's method like this:

def redefine_method_for(klass)
  def klass.class_method
    "replaced"
  end
end

redefine_method_for Thing

p Thing.class_method
#=> "replaced"

Regards,
Sean