From: dblack@...
Date: 2007-01-07T01:23:23+09:00
Subject: Re: Getting existing context when defining a singleton method (class << obj)

Hi --

On Sun, 7 Jan 2007, Roland Swingler wrote:

> Hi
>
> I'm fairly new to this "meta-programming" thing, so excuse me if I get
> my terminology wrong. Is there any way of getting access to the
> exisiting context when using class << obj or otherwise creating a
> singleton method?

Yes:

   sclass = (class << obj; self; end)
   sclass.class_eval do
     define_method ...
   end

That will keep you in the local scope you started in.

Hopefully there will be a method in Ruby 1.9/2.0 that will let you
grab an object's singleton class, so you could do:

   obj.singleton_class.class_eval   # etc.


David

-- 
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