From: "David A. Black" <dblack@...>
Date: 2007-11-17T04:51:44+09:00
Subject: Re: meta-class subclass relationships

Hi --

On Sat, 17 Nov 2007, Greg Weeks wrote:

> *Many* thanks for the info.  I was going to swallow the 1.8.6 behavior,
> but I much prefer the Figure 24.2 behavior.
>
> On the other hand, it is not true that A.class == $Meta_A.  For the
> "class" message, the rule seems to be that you follow the inheritance
> chain until you find a non-virtual class.  This would be a reasonable
> behavior for the "superclass" message too, I think.  (Preferable,
> perhaps.)
>
> As for "Meta": I don't know if the English language is precise on this
> point.  As I understand it, a meta-foo is a foo *about* foos.  A
> meta-class is a class with class instances, I would think.  Although
> most Ruby meta-classes are virtual, we can still mix modules into them,
> so they provide a powerful mechanism for meta-programming.  That's why
> I'm inclined to call them (limited) meta-classes.

I believe Jim Weirich once said that the only real metaclass in Ruby
is Class, since it's the source of class instances.


David

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