public function getMask(): IP
    {
        if ($this->mask === null) {
            if ($this->prefix == 0) {
                $this->mask = new static::$ip_class(0);
            } else {
                $max_int = gmp_init(static::$ip_class::MAX_INT);
                $mask = gmp_shiftl($max_int, static::$ip_class::NB_BITS - $this->prefix);
                $mask = gmp_and($mask, $max_int); // truncate to 128 bits only
                $this->mask = new static::$ip_class($mask);
            }
        }

        return $this->mask;
    }
public function getMask(): IP
    {
        if ($this->mask === null) {
            if ($this->prefix == 0) {
                $this->mask = new static::$ip_class(0);
            } else {
                $max_int = gmp_init(static::$ip_class::MAX_INT);
                $mask = gmp_shiftl($max_int, static::$ip_class::NB_BITS - $this->prefix);
                $mask = gmp_and($mask, $max_int); // truncate to 128 bits only
                $this->mask = new static::$ip_class($mask);
            }
        }

        return $this->mask;
    }
public function getMask ( ) : IP { if ( $ this -> mask === null ) { if ( $ this -> prefix == 0 ) { $ this -> mask = new static :: $ ip_class ( 0 ) ; } else { $ max_int = gmp_init ( static :: $ ip_class :: MAX_INT ) ; $ mask = gmp_shiftl ( $ max_int , static :: $ ip_class :: NB_BITS - $ this -> prefix ) ; $ mask = gmp_and ( $ mask , $ max_int ) ; // truncate to 128 bits only $ this -> mask = new static :: $ ip_class ( $ mask ) ; } } return $ this -> mask ; }
Return netmask.

@return IP
Return netmask .