See also List::MoreUtils

From the pod:

use List::MoreUtils qw( uniq );
my @x = uniq 1, 1, 2, 2, 3, 5, 3, 4; 

# @x now contains 1 2 3 5 4
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This method has the advantage that it maintains the order of your original list. A simple hash method will shuffle the order.