Perl Style: Use Hashes for the First Time

  • A hash is a good way to keep track of whether you’ve done something before.

  • Embrace the ... unless $seen{$item}++ notation:

        %seen = ();
        foreach $item (genlist()) {
            func($item) unless $seen{$item}++;
        }
    

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Copyright © 1998, Tom Christiansen All rights reserved.

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