anchor.diff:    (declare (ignore predicate))
     (do-port-force-output eq))
   
  -;; STANDARD-SHEET-INPUT-MIXIN
  +;;; STANDARD-SHEET-INPUT-MIXIN
   
   (defclass standard-sheet-input-mixin ()
     ((queue :initform (make-instance 'port-event-queue)
  
positive.code:             (push sheet schedule)
              (push event schedule))))))
  
  ;; PORT-EVENT-QUEUE methods
  
  (defun do-port-force-output (port-event-queue)
    (let ((port (event-queue-port port-event-queue)))
  
negative.code: 	     :initarg :delegate
  	     :accessor delegate-sheet-delegate) ))
  
  ;;; Don't know if this event queue stuff is completely right, or if it
  ;;; matters much...
  
  (defmethod initialize-instance :after ((obj delegate-sheet-input-mixin)
  				       &key input-buffer)
  