From: Reimer Behrends <behrends@...>
Date: 2002-10-11T10:35:47+09:00
Subject: Re: Sorting an array of hashes

Martin Stannard (martin@massive.com.au) wrote:
[...]
>  # create an array of Hashes. We want to sort by firstKey, then secondKey.
>  unsorted = []
>  100.times do |t|
>    unsorted.push({ "firstKey" => rand(10), "secondKey" => t})
>  end

Since all you seem to need is a lexicographic ordering, how about:

  unsorted.map{|h|[h["firstKey"],h["secondKey"],h.id,h]}.sort.map{|_,_,_,h|h}

or, in 1.7:

  unsorted.sort_by{|h|[h["firstKey"],h["secondKey"]]}

The h.id in the first case is necessary to prevent the individual
hashes from being compared, which doesn't work. In either case, we punt
by relying on the fact that <=> on arrays implements lexicographic
ordering.

[...]

			Reimer Behrends