append method

Implementation

@override
ValidationResult<M> append(ValidationResult<M> result, bool isValid) {
  return switch (result) {
    IsValid<M>() => copyWith(isValid),
    HasMessages<M>() => result.copyWith(isValid, messages: [this, ...result.messages]),
    HasMessage<M>() => HasMessages(
      isValid: isValid,
      messages: [this, result],
    ),
  };
}