Here is one way:

use strict;
use warnings;

my @names = qw(Mary Mary Mary Mary Joe Joe Joe);
my %unique;
@unique{@names} = undef;
@names = keys %unique;
print join ", ", @names;

[download]

Prints:

Joe, Mary

Update s/undef/()/ per Roy Johnson's reply

Perl is Huffman encoded by design.

In reply to Re: removing duplicate entries from an array by GrandFather
in thread removing duplicate entries from an array by Anonymous Monk

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