Using hashes can take up a lot of memory, especially with long lists. Here's one that acts like sort -u : 
my @list = sort(@list);
my @unique;
my $i=0;

$unique[0] = $list[0];

foreach my $item(@list) {
    unless($item eq $unique[$i]) {
        push(@unique,$item);
        $i++;
    }
}

[download]
@unique is now a sorted unique list.

Edit kudra, 2001-09-10 Added code tags

In reply to RE: Return a Unique Array by Anonymous Monk
in thread Return a Unique Array by Anonymous Monk

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