From: Jason Persampieri <helgaorg@...>
Date: 2002-11-27T13:32:24+09:00
Subject: Re: each_with_index & collect_with_index?

> It would be really cool if, instead of having a
> million *_with_index
> methods floating around in Enumerable, we had a
> method which could be
> used inside a block to retrieve the number of
> iterations that the block
> has undergone.
> 
> For instance:
> 
>   class Array
>     def collect( &e )
>       ary = []
>       i = 0
>       self.each { |item|
>         eval( "def index; #{i} end", e )
>         ary.push( e.call( item ) )
>         i += 1
>       }
>       return ary
>     end
>   end
> 
> The `index' method can then be used in the block:
> 
>   c = z.collect { |el| f(el, a[index], b[index]) }
> 
> This implementation is flawed, though, because it
> creates the `index'
> method in whatever namespace the block is originally
> placed.  But, you
> know.. what if?? 
> 
> _why
> 
> 

(Bear in mind... I'm a newbie ;)

Wow... I like this... or at least an slight variation.

Why not have a global var (eg $# or something) that
keeps the current index whenever you're iterating
through an array/string/whatever?  

It would be consistent, extremely useful, less
confusing and completely straightforward.

OK... let the criticism flow!

Jason