From: Hal Fulton <hal9000@...>
Date: 2005-04-01T10:56:06+09:00
Subject: Re: Syntax sugar idea for loops

Luke Graham wrote:
> 
> Internal and external iterators are equivalent given the existance
> of continuations. It may be interesting to explore the possibilities
> of representing flow control as an object. To start the debate...
> 

I wanted to jump into this thread, though my reply doesn't follow
Luke's directly.

I started a thread like this in summer of '02 -- I was looking at
some kind of iterator that would allow "normal" (internal) iteration
as well as external, and would have features like detecting even/odd,
first, and last.

An additional problem I wanted to solve was that an element in a
collection can't be replaced in that collection unless you know
the index, and thus you use each_with_index. And actually, I was
just thinking of arrays at that point, as hashes are a different
animal.

The thread is at:
http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/46337
or search for "super-iterator"...

I've been thinking more about it, and I'd do it a little differently
now... maybe I'll get a chance to implement that soon.


Cheers,
Hal