If I understand what you're after then Tie::IxHash is it.

Tie::IxHash - ordered associative arrays for Perl

I has the uniqueness of a hash and the order of an array. In your case you could just use the keys and ignored the values. You can also access all normal array operations via the tied object.

Brad

In reply to Re: Order-Preserving and Unique: Tie::IxHash by bsb
in thread Order-Preserving and Unique: List Cleanup by Intrepid

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