From: "David A. Black" <dblack@...>
Date: 2009-06-21T01:09:28+09:00
Subject: Re: 'move into' a module's namespace in irb

Hi --

On Sun, 21 Jun 2009, Max Williams wrote:

> aha...i was just playing with this in irb and found something puzzling -
> would you mind, while we're on this subject, explaining it to me?
>
>>> module M; class String; def how_long; "could be anything"; end; end; end
>
> #here, "hello" and String.new are the same class
>>> include M
> => Object
>>> "hello".class
> => String
>>> String.new.class
> => String
>
> #here, they're not the same class
>>> irb M
>>> "hello".class
> => String
>>> String.new.class
> => M::String
>
> It looks like the core String and the module's version are colliding in
> a weird way.

When you do irb M, you're putting M before all else in the constant
resolution path. So String.new is really M::String.new. "hello" is
still a ::String (top-level, core String class), because the existence
of M::String does not affect the behavior of the literal quotation
marks (which create a ::String).


David

-- 
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