anchor.diff:              sessionCache.remove(oldest);
   
           }
  -
  +        print("returning session $session");
           return session;
       }
   
  
positive.code:         int x,y;
          double diff;
          for (ObservatorySession session in sessions.values) {
              x = ((session.x + 0.5) * gridsize).floor() + session.model_offset_x - this.camx;
              y = ((session.y + 0.5) * gridsize).floor() + session.model_offset_y - this.camy;
  
  
negative.code:     ObservatorySession(ObservatoryViewer this.parent, int this.seed, int this.x, int this.y) {
          //JR: yes technically this might not finish by the time this objec ti s returned
          //JR: but observatory doesn't use any of the async bullshit anyways.
          this.rand = new Random(seed);
          init();
      }
  
      //JR: needed for the non callback paradigm
      Future<Null> init() async {
          print("Initing whatever $this is");
          this.session = await parent.getSession(seed);
  
  
          this.initial_rotation = rand.nextDouble(Math.PI * 2);
          this.rotation_speed = rand.nextDouble() * (max_rotation - min_rotation) + min_rotation;
  