cached_future

readme.md

cached_future

Created with <3 with dartpad.dev.

main.dart

import 'dart:async';

void main() {
  final s = Service();
  Future.wait([for (final _ in [0, 1, 2, 3, 4 ]) s.setup()]);
}

class Service {
  Future<void> setup() async {
    if (_completer == null) {
      _completer = Completer();
      // Do setup
      print('Start setup');
      await Future.delayed(Duration(seconds: 1));
      _completer!.complete(null);
      print('Finished setup');
      return;
    }
    print('returning future');
    return _completer!.future;
  }
  
  Completer<void>? _completer;
}