code: func StrInt64(v []byte, err error) (int64, error) {
  	if err != nil {
  		return 0, err
  	} else if v == nil {
  		return 0, nil
  	} else {
  		return strconv.ParseInt(hack.String(v), 10, 64)
  	}
  }
docs: // StrInt64 gets the 64 integer with string format.