From: Martin DeMello <martindemello@...>
Date: 2005-04-19T17:34:33+09:00
Subject: Re: [ANN] Article: Seeing Metaclasses Clearly

Jim Weirich <jim@weirichhouse.org> wrote:
> 
> So, the instances of a metaclass are classes.  Ruby happens to implement 
> metaclasses as singleton classes (or virtual classes, whatever).  So the 
> singleton class of a class is a metaclass, but the singleton class of 
> something that is not a class, would not be a meta class.
> 
> I would modify Why's metaid library thusly:
> 
>   class Object
>     def singletonclass
>       class << self
>         self
>       end
>     end
>   end
>   class Class
>     def metaclass
>       singletonclass
>     end
>   end

+1 - in fact, I think that should go into the FAQ, under "What is the
difference between a singleton class and a metaclass?"

martin