From: Markus <markus@...>
Date: 2004-10-01T09:48:33+09:00
Subject: Re: Proc.new(method)? (was Re: Funtionality of 'case'-Expression)

On Thu, 2004-09-30 at 14:12, Brian Candler wrote:
> On Fri, Oct 01, 2004 at 05:13:24AM +0900, Brian Candler wrote:
> > Perhaps it makes more sense in this particular example to subclass Proc,
> > giving a "Proc which has an === method for use in case statements":
> 
> Or arguably, just alias Proc#=== to Proc#call in the language core for use
> in case statements, in the same way as Class#=== exists primary for use in
> case statements.

     Foul.  The case case was adduced as _an_example_ of where the new
Proc functionality might be useful.  The point of extensibility feature
such as this is to _avoid_ having to extend the language core every time
it would be useful to do whatever they do.

     Alice: I'd like to add this feature.

     Bob: Why would you want that?

     Alice: Well, it would be handy in case C1.

     Bob: Oh, good idea.  We could just deal with that in the language  
         core.   So why do you want that feature again?

     Alice: Well, it would be handy in case C2.

     Bob: Yes.  I see.  We could add that to the language core 
         too.   But I still don't see why we need that feature.

     Alice: Well, it would be handy in case C3
        :


> It's interesting to observe that these objects we're talking about are the
> same as the selector blocks you'd use in Array#find and friends.

     *smile*  Isn't it though?

-- MarkusQ