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How can I make my hash remember the order I put elements into it?

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How can I make my hash remember the order I put elements into it?

Use the Tie::IxHash from CPAN.

    use Tie::IxHash;
    tie(%myhash, Tie::IxHash);
    for ($i=0; $i<20; $i++) {
        $myhash{$i} = 2*$i;
    }
    @keys = keys %myhash;
    # @keys = (0,1,2,3,...)

Source: Perl FAQ: Data Manipulation
Copyright: Copyright (c) 1997 Tom Christiansen and Nathan Torkington.

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