code: func (v *Validator) TypeInt(field string) *ValidationResult {
  	if _, err := strconv.Atoi(v.data.Get(field)); err != nil {
  		return v.addTypeError(field, "integer")
  	} else {
  		return validationOk
  	}
  }
docs: // TypeInt will add an error to the Validator if the first
  // element of data.Values[field] cannot be converted to an int.