I'm going to take a stab and say that you misunderstood the Categorized Questions and Answers node. It's not that you use the arrayref itself as the key, but that the value is an arrayref. So, you would have something like: 
my %hash = ( key1 => [1, 2, 3],
             key2 => [5, 6, 7],
           );

[download]
Then, when you wanted to get the values back, you'd do something like $hash{key1}[2] and that would give you 3.

The problem with using an arrayref as a hashkey is that the reference gets stringified. That process ends up being divorced from the actual reference, meaning you can't get to it from the key itself.

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In reply to Re: Arrays as Hash Values by dragonchild
in thread Arrays as Hash Values by c

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