From: David Vallner <david@...>
Date: 2007-02-19T23:16:14+09:00
Subject: Re: Why should initialize_copy verify the class of the original?

On Sun, 18 Feb 2007 17:10:06 +0100, Jeremy Henty <jeremy@chaos.org.uk>  
wrote:

> I was looking at the CD player example in the Pickaxe book and I can't
> see why their C implementation of CDPlayer#initialize_copy needs to
> check that the original object is an instance of CDPlayer .  Isn't
> this always the case?  If #initialize_copy is only called from inside
> #dup or #clone then surely the receiver has to be of the same class as
> the original!  What am I missing?
>

CDPlayer.new.instance_eval {initialize_copy(TeddyBear.new)}

Which would probably cause the C implementation to do Bad Things without  
said check.

David Vallner