future_queue

Dart package which provides sequential future execution with return values.

How it works

Here is a code example which demonstrates how futures are queued:

final futureQueue = FutureQueue<int>(seed: 0);

final result1 = futureQueue.append(
  () => Future.delayed(Duration(seconds: 5), () => 1),
);
final result2 = futureQueue.append(
  () => Future.delayed(Duration(seconds: 1), () => 2),
);

print('result1: ${await result1}');
print('result2: ${await result2}');

Will print:

1
2

Allowing null

Simply set the type of the FutureQueue to a nullable value:

final futureQueue = FutureQueue<int?>(seed: null);

Even though the first future takes 4 seconds longer than the second future.

Error handling

If the future throws an exception it can be caught, as usual, by chaining a catchError on the Future returned by FutureBuilder's append.