This may quickly become a golf question, a colleague wrote a subroutine over 50 lines to solve this one.

I have an array which looks a lot like a hash. It has key/value pairs, and has a guaranteed even length. The only thing stopping it from being a hash is that some keys are repeated. I want to turn it into a hash, by making each value into an arrayref containing all the values with that key. eg. 
$in = [ one => 1, two => 2, two => '2.003' ];
    # must become
$out = { one => [1], two => [ 2, '2.003' ] };

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The order of the values in the original array is not important (as if it were a hash), and the order of the values in the new array refs is also unimportant.

Update
I should have mentioned, I'm stuck with perl5.6 for this task. I would, however, be interested in how it might look in perl6!


- Boldra

In reply to my array is almost a hash, but keys are not unique. by Boldra

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