I'm sort of new to this, so maybe this is just 'baby talk', but this has always worked for me: push @arr, $el if !$seen{$el}++; The hash value $seen{$el} is not incremented until after the test and so is always zero the first time through, non-zero thereafter.

In reply to Re: Determining if an element is already in an array. by Anonymous Monk
in thread Determining if an element is already in an array. by ithron

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