Either

readme.md

Either

Created with <3 with dartpad.dev.

main.dart

void main() async {
  await getAll();
}

Future<void> getAll() async {
  final <Either>[name, value] = await Future.wait([
    getName(),
    getIdade(),
  ]);

  switch ((name, value)) {
    case (Success(value: final name), Success(value: final idade)):
      print('Success: Nome: $name, idade: $idade');
    case _:
      print('Um deles falhou.');
  }
}

Future<Either<Exception, String>> getName() async {
  return Future.delayed(const Duration(seconds: 4), () => Success('Lucas'));
}

Future<Either<Exception, int>> getIdade() async {
//   return Future.delayed(const Duration(seconds: 1), () => Success(13));
  return Failure(Exception('falha em getIdade'));
}

sealed class Either<E extends Exception, S> {}

class Success<E extends Exception, S> extends Either<E, S> {
  final S value;
  Success(this.value);
}

class Failure<E extends Exception, S> extends Either<E, S> {
  final E exception;
  Failure(this.exception);
}

class Nil {
}