Depending on what exactly you want to do with undefined values, this works. 
#!/usr/bin/perl -w
@a=qw(ala ma kota tytus ma kolty a pies ma ale);
print join ", ", uniq( sort @a),"\n";

sub uniq {
  my $last;
  map { (defined($last) && $last eq $_) ? () : ($last = $_) } @_;
}

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"What should it profit a man, if he should win a flame war, yet lose his cool?"

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

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