Just a followup at (my) current end of the thread:

On 16 Aug 2001, at 13:56, Yukihiro Matsumoto wrote:

> |Yes, I know a "become" which may not be used on all objects is far from
> |being orthogonal, but maybe still usefull
> 
> Maybe useful for some cases.  Maybe nightmare for some cases.

I just remembered another situation where "become" could be 
useful. I saw it somewhere sometime, but don't remember the 
details.

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.

> "become" is too strong.
> 							matz.

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 : )

Pit