From: Christopher Dicely <cmdicely@...>
Date: 2010-08-28T06:34:55+09:00
Subject: Re: Lazy array

On Sun, Aug 1, 2010 at 3:45 PM, Andrew Wagner <wagner.andrew@gmail.com> wrote:
> How can I get a lazy array in Ruby? E.g., in Haskell, I can talk about
> [1..], which is an infinite list, lazily generated as needed. I can also do
> things like "iterate (+2) 0", which applies whatever function I give it to
> generate a lazy list. In this case, it would give me all even numbers.
> Anyway, I'm sure I can do such things in Ruby, but can't seem to work out
> how.

The Ruby equivalent of a lazy array is an enumerator. In Ruby 1.9.2,
you can get an infinite list of positive integers as:

(1..Float::INFINITY).to_enum,

For non-negative even integers, you could do:
(0..Float::INFINITY).step(2)