Resultex | Functional Error Handling for Dart & Flutter

Functional Architecture

Encapsulate Success data and Failures into explicit types. Avoid runtime crashes caused by unhandled implicit exceptions.

Clean Architecture Ready

Designed specifically to protect Use Cases and Repositories. Safely catch Data Layer issues and bubble them up cleanly to your BLoC/Cubit.

Zero Dependencies

Ultra lightweight, performant, and completely dependency-free. Blends seamlessly into any standard Dart or Flutter codebase.

Installation

Add Resultex to your Flutter project with a single command:

$ flutter pub add resultex

How It Works

Replace error-prone try-catch blocks with clear, declarative code flow control.

example_repository.dart

// 1. Define a function that explicitly promises a Success or Failure
Result<User, Failure> getUserProfile(String userId) {
  try {
    final user = api.fetchUser(userId);
    return Result.success(user);
  } catch (exception) {
    return Result.failure(ServerFailure(exception.toString()));
  }
}

void main() {
  // 2. Execute and process the returned state securely
  final result = getUserProfile("user_99");

  // Flow-control using smooth fold pattern matching
  result.fold(
    onSuccess: (user) => print("Success: Active user is ${user.name}"),
    onFailure: (failure) => print("Error encountered: ${failure.message}"),
  );
}