#Flutter/Riverpod - Is it possible to call only error when using AsyncNotifier?

Question

I am using riverpod as state management for my flutter project and am currently working on auth services. I am having AuthNotifier extending AsyncNotifier. The problem is when i make a call to the AuthService for example like that:

Future<void> logout() async {
    state = const AsyncValue.loading();
    state = await AsyncValue.guard(() async {
      return await authService.logout();
    });
    state.when(
      data: (data){},
      error: (error, stackTrace){
        ref.read(errorProvider.notifier).createException(exception: error.toString(), errorTitle: "Logout Error");
      },
      loading: (){},
    );
  }

I am only using the error in the state.when but i also have this unused code.

I tried looking for at the methods of state or state.when but couldn't find anything either because the answer is not there or because i didn't see it. If anyone has alternative on handling the error inside the Notifier i am open to suggestions.

Answer 1

Use whenOrNull/mapOrNull or maybeWhen/maybeMap to handle only some states, for example:

final Object? newState = state.whenOrNull(
      error: (error, stackTrace){
        ...
      },
    );

// or

final Object newState = state.whenOrNull(
      orElse: () => ...,
      error: (error, stackTrace){
        ...
      },
    );