method

join

Source

/**
 * Collects string of data events' string representations.
 *
 * If [separator] is provided, it is inserted between any two
 * elements.
 *
 * Any error in the stream causes the future to complete with that
 * error. Otherwise it completes with the collected string when
 * the "done" event arrives.
 */
Future<String> join([String separator = ""]) {
  _Future<String> result = new _Future<String>();
  StringBuffer buffer = new StringBuffer();
  StreamSubscription subscription;
  bool first = true;
  subscription = this.listen(
    (T element) {
      if (!first) {
        buffer.write(separator);
      }
      first = false;
      try {
        buffer.write(element);
      } catch (e, s) {
        _cancelAndErrorWithReplacement(subscription, result, e, s);
      }
    },
    onError: (e) {
      result._completeError(e);
    },
    onDone: () {
      result._complete(buffer.toString());
    },
    cancelOnError: true);
  return result;
}