From: "David A. Black" <dblack@...>
Date: 2003-12-04T04:09:59+09:00
Subject: Re: each_with_what_index?

Hi --

On Thu, 4 Dec 2003, Hugh Sasse Staff Elec Eng wrote:

> On Wed, 3 Dec 2003, T. Onoma wrote:
> 
> >
> > Saying that there's "absolutely nothing unintutive about that" is a real
> > stretch. Obviously, I have asked for certain indexes [1..-1], but we know
> > that #[ ] is really just a form of slice, so what we get is a new array, thus
> > reindexed form [0..a.length-2]. It's understandable, but I sure wouldn't call
> > it intuitive.
> 
> Suppose if each_with_index allowed a range parameter
>    a.each_with_index(1...a.size) {|t,i|...}
> Would that be worth an RCR?  It looks sort of natural to me, but...

Just for fun:

  module Enumerable
    def each_with_index(range=(0...size))
      range.each {|i| yield at(i),i}
    end
  end

though it doesn't do much for me.  I guess I haven't seen the problem
to which it would be a solution, and it seems to be based on a sort of
rollback of the original request (i.e., here's a enumerable; give me
its elements and their indices; wait, actually, don't act on the
receiver but on a subsequent restraint...).  It feels inside-out to
me.


David
-- 
David A. Black
dblack@wobblini.net