anchor.diff:      return __waitEqualsMaxWait;
     }
     bool __waitEqualsMaxWait;
  -  
  -  /// Requires a [wait] period to elapse *with no input events* after any 
  +
  +  /// Requires a [wait] period to elapse *with no input events* after any
     /// previous event before emitting the next event.
  -  /// 
  -  /// If [maxWait] is provided, then it specifies the maximum wait period 
  +  ///
  +  /// If [maxWait] is provided, then it specifies the maximum wait period
     /// before events can be emitted again.
  -  /// 
  +  ///
     /// If [maxWait] is less than [wait], throws an [ArgumentError].
  -  /// 
  -  /// If [leading] is true, then events which do not occur in a wait period 
  -  /// are emitted immediately, otherwise they will be emitted at the end of the 
  +  ///
  +  /// If [leading] is true, then events which do not occur in a wait period
  +  /// are emitted immediately, otherwise they will be emitted at the end of the
     /// wait period.
  -  /// 
  -  /// If [trailing] is true, then the last event to occur in a wait period will 
  +  ///
  +  /// If [trailing] is true, then the last event to occur in a wait period will
     /// be output at the end of the wait period.
  -  /// 
  +  ///
     /// If both [leading] and [trailing] are false, throws an [ArgumentError].
     Debouncer(
  -      Duration wait, 
  -      {Duration maxWait, 
  -       bool leading: false, 
  -       bool trailing: true}) : 
  +      Duration wait,
  +      {Duration maxWait,
  +       bool leading: false,
  +       bool trailing: true}) :
          _wait = wait,
          _maxWait = maxWait,
          _leading = leading,
  
positive.code: }
  
  /// Enforces a *quiet* wait period between events.
  class Debouncer<T> implements StreamTransformer {
  
    final Duration _wait;
    final Duration _maxWait;
  
negative.code:             controller = new StreamController<T>(
                onListen: () {
                  subscription = input.listen((data) {
  
                    addData = _trailing;
                    lastData = data;
                    bool setTimer = false;
  