From: Trans <transfire@...>
Date: 2007-02-19T12:03:50+09:00
Subject: Re: More flexible inheritance



On Feb 18, 2:49 pm, Gary Wright <gwtm...@mac.com> wrote:
> On Feb 17, 2007, at 8:24 PM, Trans wrote:
>
> > A notion came to me yesterday with regards to how we extend classes.
> > On the one hand we can create a module and include it into a class,
> > but this will not allow us to override a preexisting method -- for
> > that we must reopen the class and play the alias and/ or binding game.
>
> Why not just use a subclass?  Isn't that one of the primary motivations
> for inheritance in the first place, to override a method in an ancestor?

You're right of course --if that's what one needs. But often one wants
to extend a prexisting class. There are numerous reasons one might
want to do that, and which arn't very suitable to subclassing.
Imagine if we didn't have open classes , then just to add a single
method to a class required a new subclass. (would Ruby start to look a
lot more like Java?)

T.