avdosev / either_dart Goto Github PK

I'm using either_dart in getter-setter.
But I'm stuck while adding data to the list. I want to add data to the list using pagination So can you please guide me that how can i add data to the list?

Here is my code,

 Either<List<NotificationResponseData>, Exception> _notificationData = Right(SuccessResultException());
  Either<List<NotificationResponseData>, Exception> get notificationData => _notificationData;
  set notificationData(Either<List<NotificationResponseData>, Exception> value) {
    _notificationData = value;
    // _notificationData.fold((left) => value.left, (right) => value.right);
    notifyListeners();
  }

In 1.0.0 the Either class was sealed. This breaked the generated mocking code for unit tests.

Is there a need for this class to be sealed?

We are forced to remain on version 0.4.0 - please reconsider sealing.

Thank you

I am quite new to dart so I may be wrong here (that's why I am creating an issue rather then pull request) but shouldn't fnL and fnR return FutureOr<T> instead of T?

Future<T> fold<T>(FutureOr<T> Function(L left) fnL, FutureOr<T> Function(R right) fnR) {
  return this.then((either) => either.fold(fnL, fnR));
}

This is what this.then() actually expects and it would allow us to do something like this:

bool success = await getStatusAsync()
  .fold(
    (error) async {
      await saveErrorAsync(error);
      return false;
    },
    (status) async {
      await saveStatusAsync(status);
      return true;
    },
);

(it's just and example and my usecase is actually quite different but I also need to fold both left and right to different futures of the same type)

Any guidelines how to migrate existing code?

https://dart.dev/language/class-modifiers#sealed

Admittedly I haven't dug too deep here - but seems like a sealed annotation would be a nice addition for this lib.

Might need to be a separate package to maintain compatibility with Dart < 3.0.

Happy to take a stab at it at some point in the next week or two if you'd like!

    test('should be same', () {
      final x = Left('test');
      final z = Left('test');
      expect(x, z);
    });

Result:
Expected: <Instance of 'Left<String, dynamic>'>
Actual: <Instance of 'Left<String, dynamic>'>