From: matz@... (Yukihiro Matsumoto)
Date: 2001-12-21T12:24:14+09:00
Subject: [ruby-talk:29196] Re: Why is UnboundMethod a subclass of Method? (was Re: overriding methods: (almost) a replacement for alias_method)

Hi,

In message "[ruby-talk:29182] Re: Why is UnboundMethod a subclass of Method? (was Re: overriding methods: (almost) a replacement for alias_method)"
    on 01/12/21, "Chr. Rippel" <chr_news@gmx.net> writes:

|> Well, a Method is really a BoundMethod, and a BoundMethod is not an
|> UnboundMethod.  In my mind, it doesn't really make sense to have Method
|> inherit from UnboundMethod.

|Subclassing (Bounded)Method from UnboundedMethod is much less
|problematic (only bind needs to be overridden with the sematics ``rebind")
|but as Guy points out UnboundMethod already exists in 1.6 so there is no
|chance that this will be changed in 1.8.

For your information, it's almost historical reason.  I developed
Method (BoundMethod) first, not knowing UnboundMethod was possible.

If I was introducing both BoundMethod and UnbountMethod at the same
time, it might be

  Method
    BoundMethod
    UnboundMethod

or might be as you said

  UnboundMethod
    BoundMethod

due to my less-class-ism.

Anyway, consider they are not in is-a relation.  They are just sharing
implementaion.

							matz.
p.s.
You're bind - rebind idea sounds nice.