From: Dave Thomas <Dave@...>
Date: 2000-09-17T02:28:04+09:00
Subject: [ruby-talk:4943] Re: Perl 6 rumblings -- RFC 225 (v1) Data:  Superpositions

Mark Slagell <ms@iastate.edu> writes:

> At first glance, I like the idea of any/all -- they seem to have broad
> applicability.
> 
> Alternative name suggestions: "any_satisfies" and "all_satisfy" are
> more descriptive but a bit long - maybe just adding question marks
> would be good: "any?" and "all?".

I like any? and all? We might want to make 'exists?' an alias for
'any?', and 'none?' == '!all?'.


Could I also vote for 'count'

    thing.count { |i| i > 3 }


Then... do we add it to Enumerable, so do we put it in a separate
library

   module Enumerable
      include Existential

  end


Why do this? Two reasons. First, it avoids cluttering Enumerable
(that's a poor reason). The second is that we get to play with it
before committing changes to the interpreter. I'm thinking that we
implement it in Ruby, and put the source in lib/. We then see if it is 
useful and if it is actually used. If so, and if the performance hit
of implementing it in Ruby proves to be too great, we can then move it 
in the the C source.

In general, I'm thinking that this is a good way to do all kinds of
new features: implement them first in Ruby before adding bulk to the
interpreter.


Regards


Dave