From: ara.t.howard@...
Date: 2006-01-11T14:33:05+09:00
Subject: Re: Stupid question from a Ruby newb

On Wed, 11 Jan 2006, Will wrote:

> Hi folks, I know that this is a really simple question, and there must
> be many ways to do it in Ruby...  but what I'm looking for is an
> elegant way to take a collection of objects and create a hash mapping
> one attribute of the object as the key and the other as the value.  So
> far what I am doing is this:
>
> objects = some_method_to_return_collect( method_params )
> myHash = Hash.new
>
> @objects.each do |object|
>  myHash[ object.key ] = object.value
> end
>
> I played around with doing something like:
>
> @myHash = objects.map do |object| [ object.key => object.value ] end
>
> But that returns an array of single-value hashes, which is not exactly
> what I am trying to do.
>
> I know this is a stupid question, and probably pointless because I do
> know ways to do it, but I would really like the know the Ruby Way to do
> this.  Ruby seems so given to elegant code that my code above really
> bugs me for some reason.
>
> Thanks all!

   h = objects.inject({}){|h,o| h.update o.key => o.value}

-a
-- 
strong and healthy, who thinks of sickness until it strikes like lightning?
preoccupied with the world, who thinks of death, until it arrives like
thunder?  -- milarepa