anchor.diff:       &key (repaint t) (erase #'erase-output-record)
        feedback finish-on-release multiple-window
        feedback-event erase-final)
  -  (declare (ignore erase repaint multiple-window))
  +  (declare (ignore erase repaint))
     (let ((feedback-event-fn
   	 (cond (feedback-event
   		feedback-event)
  
positive.code:       (multiple-value-bind (x0 y0)
  	  (stream-pointer-position stream)
  	(funcall feedback-event-fn record stream x0 y0 x0 y0 nil)
  	(tracking-pointer (stream)
  	 (:pointer-motion (&key event x y)
  	   ;; XXX What about the sheet?
  	   (funcall feedback-event-fn record stream x0 y0 x y event)
  
negative.code:                  (draw x y)
                   (setf ox x oy y))
                 (end (event x y)
                   (when ox (draw ox oy))
                   (return-from dragging-drawing
                     (values x y))))
          (tracking-pointer (stream :pointer pointer
                                    :multiple-window multiple-window)
            (:pointer-motion (window x y)
              (motion x y))
            (:pointer-button-press (event x y)
              (end event x y))
            (:pointer-button-release (event x y)
              (when finish-on-release
                (end event x y))))))))
  
  (defun pointer-place-rubber-band-line* (&key (stream *standard-output*)
                                          (pointer (port-pointer (port stream)))
  