From: Jonathan Leighton <lists@...>
Date: 2006-01-31T20:08:58+09:00
Subject: Re: Loop weirdness

On Tue, 2006-01-31 at 06:27 +0900, Simon Kr旦ger wrote:
> > 
> > I did, back in the thread a little:
> 
> Sorry, missed that.
> 
>   > But don't worry about it, I am happy with the solution I've found. (That
> > is, there is no longer a *problem*, although I'm always interested to
> > see better/leaner/cleaner ways of doing things).
> 
> :) another try:
> 
> def categorise(items)
>    items.inject([]) do |a, item|
>      ary = a.assoc(item[:num]) || (a << [item[:num], []]).last
>      ary.last << item[:foo]; a
>    end.map{|k, v| {:num => k, :items => v}}
> end

That's pretty slick :). One question though:

The docs say Array#map only yeilds on value: the value of the item in
the array. However, you are using two in your block. I understand (from
looking at the code), that this assigns each value in the item array to
k and v respectively, but how does that work? Is there any docs about
that anywhere?

Cheers

-- 
Jonathan Leighton
http://turnipspatch.com/ | http://jonathanleighton.com/ | http://digital-proof.org/