// Single Stream

  StreamController<String> controller = StreamController<String>();

  // Setup listener

  controller.stream.listen(

    (data) => print('Received data: ${data.toUpperCase()}'),

    onDone: () => print('done'),

    onError: (e) => print('error $e')

  );

  // Emit event

  controller.add('Hello');

  controller.add('World');

  // trigger error

  controller.addError('Throwing this error');

  // trigger done

  await controller.close();

  print('after done, return future, clean up');

// Broadcast Stream

  StreamController<String> controller2 = StreamController<String>();

  Stream<String> boradcast = controller2.stream.asBroadcastStream();

  boradcast.listen((data) => print('Received data: $data'));

  boradcast.listen((data) => print('Received data again: $data'));

  controller2.add('Hello1');

  controller2.add('World2');

 // Future-based streams

  Future<String> result = HttpRequest.getString('https://swapi.co/api/people/1');

  Stream<String> resultStream = Stream.fromFuture(result);

  resultStream.listen(

    (data) => print('Got data: $data'),

    onError: (e) => print(e.type),

    onDone: () => print('No more data on stream.')

  );

  // Future-based multi streams

  Future<String> result2 = HttpRequest.getString('https://swapi.co/api/people/2');

  Stream<String> peopleStream = Stream.fromFutures([result, result2]);

  peopleStream.listen(

    (person) => print('=> Got person: $person'),

        onDone: () => print('No more people on stream.')

  );

  // Typeahead

  List<String> chars = 'Dart is awesome'.split('');

  Stream<String> charStream = Stream.fromIterable(chars);

  var idx = ;

  charStream.listen((char) {

    Timer(Duration(milliseconds: idx * ), () => print(char));

    idx++;

  });