From: Erwan David <Erwan.David@...>
Date: 2001-08-16T19:14:07+09:00
Subject: [ruby-talk:19883] Re: Why not?: Assigning to self

matz@ruby-lang.org (Yukihiro Matsumoto) writes:

> Hi,
> 
> In message "[ruby-talk:19867] Re: Why not?: Assigning to self"
>     on 01/08/16, "Pit Capitain" <pit@capitain.de> writes:
> 
> |Take the famous Shape class hierarchy:
> |
> |class Shape; ...; end
> |class Rectangle < Shape; ...; end
> |class Square < Rectangle; ...; end
> |
> |Suppose you have a Rectangle instance and use one of its resizing 
> |methods so that the new height equals the new width. After that it 
> |would be nice if the Object had become a Square instance.
> 
> I feel you're relying too much on inheritance hierarchy.  In Ruby,
> it's at best implementation sharing.

Well that's seems not to me inheritance for me, but definition by
constraints... And I do not know any language implementing this...
(IE defining that a square is a rectangle which verifies the
constraint that width = heigth).

-- 
 > Quant � ma mauvaise quote de mail , d�sol�, c'est Outlook qui coupe tout
 > seul � 76. (pour ton r�pertoire de neuneuX, si tu veux)
 > (comme les lignes font d�j� 76, avec les quotes, forc�ment, �� d�passe)
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