if len(text) == 0 {
		*ip = Addr{}
		return nil
	}
	var err error
	*ip, err = ParseAddr(string(text))
	return err
}

func (ip Addr) marshalBinaryWithTrailingBytes(trailingBytes int) []byte {
	var b []byte
	switch ip.z {
	case z0:
		b = make([]byte, trailingBytes)
	case z4:
		b = make([]byte, 4+trailingBytes)