From: "T. Onoma" <transami@...>
Date: 2003-12-15T01:11:22+09:00
Subject: Re: inplace assignment

On Sunday 14 December 2003 03:59 pm, David A. Black wrote:
> I'm not sure what you mean by "duck similar" (the notion of duck
> typing doesn't scale well to "duck <this and that>"), but assuming you
> mean a class that defines methods with the same names and arities as
> another class, the best thing would probably be to do:

See, you knew exactly what I was talking about, and I only used two words! 
Seems to scale fairly well ;-)

>    module A;  # bunch of methods; end
>    module B;  # same-named methods as A; end
>
>    class C; include A; end
>    class C; include B; end   # when you want the new ones
>
> or
>
>    class C; include A; end
>    c = C.new
>    obj.extend(B)
>
> > Okay, so it's a bit crazy. But I actually came across a use for this.
> > Luckly my situation is specialized --I am replacing the class with a
> > subclass of it, so I discovered that I could just do this:
> >
> >   class MyClass < MyClass
>
> Yikes.  I *think* that resorting to that is a reasonably good
> indication that you might want to look for a new program design :-)

Well, I'm working on some method wrapping implementaions, seeing how far I can 
coerce Ruby into doing some of the things Peter and I are talking about. So 
Yikes aren't too out of the ordinary.

But, I actually did find a better way to do it this morning, by redefining 
MyClass#new to return a subclass of itself instead. Hmm..I forget, what kind 
of design pattern is that?

Thanks,
T.