From: matz@... (Yukihiro Matsumoto)
Date: 2003-04-24T17:28:00+09:00
Subject: Re: [ANN] Ruby.shop

Hi,

In message "Re: [ANN] Ruby.shop"
    on 03/04/24, Mauricio Fern�ndez <batsman.geo@yahoo.com> writes:

|    /*
|     * Ruby's Class Hierarchy Chart
|     *
|     *                           +------------------+
|     *                           |                  |
|     *             Object---->(Object)              |
|     *              ^  ^        ^  ^                |
|     *              |  |        |  |                |
|     *              |  |  +-----+  +---------+      |
|     *              |  |  |                  |      |
|     *              |  +-----------+         |      |
|     *              |     |        |         |      |
|     *       +------+     |     Module--->(Module)  |
|     *       |            |        ^         ^      |
|     *  OtherClass-->(OtherClass)  |         |      |
|     *                             |         |      |
|     *                           Class---->(Class)  |
|     *                             ^                |
|     *                             |                |
|     *                             +----------------+
|     *
|     *   + All metaclasses are instances of the class `Class'.
|     */
|
|Note that if I read this right Object doesn't inherit Class but
|extends it, as if we had
|	Object.extend Class
|which of course doesn't work since Class.class != Module.
|
|I thus believe the loop at the top of the poster is just wrong.

The vertical relationships (e.g. one between Module and Object) are
class-superclass relations.  Class's superclass is Module; Module's
superclass is Object.

The horizontal relationships are class-metaclass relations.  Class has
its unnamed singleton class (metaclass), and its superclass is a
metaclass for Module, and so forth.

I hope this explains the figure.  I believe it's not wrong.


							matz.