From: matz@... (Yukihiro Matsumoto)
Date: 2001-08-16T18:46:54+09:00
Subject: [ruby-talk:19878] Re: Why not?: Assigning to self

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.

|I like the idea of having "become", if we can define understandable 
|semantics and a safe implementation. Maybe we can find a way to 
|not let "become" become too strong : )

Maybe.  I can wait for a genius to come up with a great idea.

							matz.