From: Xavier Noria <fxn@...>
Date: 2007-05-01T22:05:36+09:00
Subject: Re: cyclic array

On Apr 30, 2007, at 11:13 AM, Xavier Noria wrote:

> On Apr 30, 2007, at 3:43 AM, Rick DeNatale wrote:
>
>> On 4/28/07, Xavier Noria <fxn@hashref.com> wrote:
>>
>>>
>>> This is a possible approach:
>>>
>>>    module Enumerable
>>>      def each_cycle(window, start=0)
>>>        (start...length+start).each do |i|
>>>          yield((i..i+window).map {|n| self[n % length]})
>>>        end
>>>      end
>>>    end
>>
>> This method won't work for Enumerables in general, although I  
>> guess it
>> does work for Arrays.
>>
>> Not all enumerables have one or both length or [] methods.
>
> Oh right, thank you. I don't know why ri Enumerable lists length here

It took me a while to discover where that non-core Enumerable#length  
reported by ri/fri comes from, it is defined by RGL in the file

   rgl-0.2.3/lib/rgl/base.rb

I've learned that ri offers --system the hard way :-).

-- fxn