It's in perlfaq4 "How can I remove duplicate elements from a list or array?".

Also, your line 19: 

{push @out,$a;} unless (defined($lasta) && ($lasta eq $a));

[download]
gives me a syntax error.

In reply to Re: Finding unique elements in an array by eyepopslikeamosquito
in thread Finding unique elements in an array by Eyck

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