From: Rob Biedenharn <Rob@...>
Date: 2009-09-29T06:07:12+09:00
Subject: Re: Noob - loop indexing

On Sep 28, 2009, at 4:49 PM, Paul Smith wrote:
> On Mon, Sep 28, 2009 at 9:46 PM, Paul Smith  
> <paul@pollyandpaul.co.uk> wrote:
>> On Mon, Sep 28, 2009 at 9:43 PM, Simon Willard <simonwillard@gmail.com 
>> > wrote:
>>> I try to make Ruby loops using "each" like this:
>>>
>>> # a is an array
>>> a.each do  ...  end
>>
>> a.each_index do |i|
>>  a[i]...
>> end
>
> Or
>
> a.each_with_index do |x, i|
>  #here, x is a[i]
>  puts x,i
> end

But just as importantly, ask yourself the question:
   "Why do I need the index? Am I not letting the objects do their  
thing?"


On Sep 28, 2009, at 4:43 PM, Simon Willard wrote:
> But this feels clunky and less Ruby-like.  Is there a way to access  
> the
> index in an "each" loop?  Is there a more elegant way to create an
> indexed loop?

If your question were a bit different, then the answer might be:

a.length.times do |i|
   #...
end

or even

(0...a.length).each do |i|
   #...
end
# and note the use of the ... range constructor that excludes its end.

(and, of course, it's up to you to formulate the appropriate  
question ;-)

-Rob

Rob Biedenharn		http://agileconsultingllc.com
Rob@AgileConsultingLLC.com