If you want to keep the items in order by first appearance, try using a side hash as an insertion guard. 
use strict;
 
my %guard;
my @unique;
 
while (<>) {
   chomp;
   push @unique,$_ if (!exists $guard{$_});
   $guard{$_} = 1;
}
print join(" ",@unique),"\n";

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In reply to Re: unique elements in an array by tall_man
in thread unique elements in an array by Anonymous Monk

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