use NetAddr::IP; my @addr = ( [ 'localhost', '0.0.0.0' ], [ '10.0.0.0/24', '0.0.0.255' ], [ '192.168.0.0/16', '0.0.255.255' ], [ '10.128.0.1/17', '0.0.127.255' ] ); $| = 1; print "1..", 2 * scalar @addr, "\n"; my $count = 1; for my $a (@addr) { my $ip = new NetAddr::IP $a->[0]; if ($ip->wildcard eq $a->[1]) { print "ok $count\n"; } else { print "not ok $count\n"; } ++$count; if (($ip->wildcard)[1] eq $a->[1]) { print "ok $count\n"; } else { print "not ok $count\n"; } ++$count; }