From: "David A. Black" <dblack@...>
Date: 2008-01-03T11:42:07+09:00
Subject: Re: singleton-of-singleton is Class in 1.9.0

Hi --

On Wed, 2 Jan 2008, Sylvain Joyeux wrote:

> In 1.9.0, the singleton of a singleton is Class, while in 1.8 it was a
> singleton itself (see below). Is that an intended behaviour just to
> make singletons slightly different than real classes, or is it a bug ?
>
> [~]% irb1.9
>>> obj = Object.new
> => #<Object:0x3026d420>
>>> sing = class << obj; self end
> => #<Class:#<Object:0x3026d420>>
>>> sing_of_sing = class << sing; self end
> => Class
>
> [~]% irb
>>> obj = Object.new
> => #<Object:0x301b2940>
>>> sing = class << obj; self end
> => #<Class:#<Object:0x301b2940>>
>>> sing_of_sing = class << sing; self end
> => #<Class:#<Class:#<Object:0x301b2940>>>

I would think it must be a bug. It makes it impossible to add class
methods of a singleton class, which would be an odd limitation. (Maybe
not the most frequent use case, but even so.)


David

-- 
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