use NetAddr::IP; my $loopback = new NetAddr::IP '127.0.0.1', '255.0.0.0'; my $rfc1918 = new NetAddr::IP '10.0.0.0/8'; my $another = new NetAddr::IP '1.2.0.0/255.255.0.0'; my $loopback2 = new NetAddr::IP 'loopback';