rbaecker@www-devel-rbaecker ~/seibert $ vi set.pl
#!/usr/bin/perl

use strict;
use warnings;

use Set::Array;

my $set_a = Set::Array->new(1, 2, 3);
my $set_b = Set::Array->new(3, 4, 5);
$set_a->union($set_b);

$set_a->join( '-' )->print;
rbaecker@www-devel-rbaecker ~/seibert $ perl set.pl
4-1-3-2-5