From: Devin Mullins <twifkak@...>
Date: 2005-07-28T14:03:08+09:00
Subject: Re: What's so special about operators, built-in classes and modules?

Yukihiro Matsumoto wrote:

>I'm sorry that I don't get it.  We call it mixin inheritance because
>mixin (modules) have some restrictions over classes:
>
>  * no superclass (although including other mixin is allowed)
>  * no instance
>
>which make mixin inheritance as it is.  Allowing "include" method to
>include classes removes above restrictions.  Then that's no different
>from multiple inheritance, in my opinion.
>  
>
OK. It sounds like you're laying down the law and prohibiting a certain 
course of action because you think it's ugly, not because it's hard to 
implement clearly and unamiguously. That's fine. I respect that. Good to 
know. :)

>Besides all of them, I don't understand why this issue arise again and
>again.
>
'Cause it's a mailing list, and we like to complain! Also, I'm new here, 
so I wasn't around for the last flurry.

>  _I_ encourage mixin inheritance.  It is powerful enough to
>solve the problem in single inheritance (sharing code between classes
>beyond inheritance line, without copy&paste).
>
Agreed.

>  Why people want "real"
>multiple inheritance by unifying classes and modules, when Ruby's
>mixin inheritance works quite well?  Why people want unnecessary
>complexity?  Just because other languages do?  I'm curious.
>  
>
My main driver was that the relationship between Module and Class is 
confusing. Everything else was just intellectual flight-of-fancy, and I 
apologize if I made it sound otherwise, or if I pissed you off.

>Interestingly, a few have complained for the lack of goto in
>Ruby. Goto is much more powerful control structure than while, break,
>next, etc.  We can construct others using goto.  I wander why no one
>propose to unify them.  ...No,  Don't.  I will refuse.
>  
>
Yep. It definitely sounds like you're laying down the law and 
prohibiting a certain course of action because you think it's ugly. :)

Devin
...brownie points if you notice the thing about this email that I don't 
want you to notice...