From: Florian Frank <flori@...>
Date: 2007-11-29T05:00:28+09:00
Subject: Re: Ruby needs continuations...

ara.t.howard wrote:
>>   a.zip(b, c, d, ...)
>
> when a, b, c, and d are large it's most undesirable to use zip, 
> forcing one to use
>
> lists = a,b,c,d
> n = lists.map{|list| list.size}.max
>
> (0 ... n).each do |i|
>   ai, bi, ci, di = lists.map{|list| list[i]}
>   # ...
> end

zip doesn't force you to do this, you can also pass a block to zip. In 
Ruby 1.9. zip without a block won't create and return an array anymore, 
but it will return an Enumerator object as a promise instead.

> and, when b, c, and d are heterogeneous containers the above code is 
> most often impossible - you will first need to convert all the 
> containers to lists and then iterate.
If you want zip to act smarter on it's arguments you will have to use 
Ruby 1.9.

-- 
Florian Frank