anchor.diff:      }
     }
   
  +  /// Stops all actions currently being run by the controller and removes them.
  +  ///
  +  ///     myNode.actions.stopAll();
     void stopAll() {
       for (int i = _actions.length - 1; i >= 0; i--) {
         _stopAtIndex(i);
  
positive.code:   double get duration => 0.0;
  }
  
  abstract class ActionInterval extends Action {
    double _duration;
  
    bool _firstTick = true;
    double _elapsed = 0.0;
  
    double get duration => _duration;
    Curve curve;
  
    ActionInterval([this._duration = 0.0, this.curve]);
  
negative.code:   void fire();
  }
  
  /// An action that calls a custom function when it is fired.
  class ActionCallFunction extends ActionInstant {
    ActionCallback _function;
  
    /// Creates a new callback action with the supplied callback.
    ///
    ///     var myAction = new ActionCallFunction(() { print("Hello!";) });
    ActionCallFunction(this._function);
  
    void fire() {
  