anchor.diff:                     (checklist .checklist)
                      (type .type)
                      (current-item-number .current-item-number)
  -                   (mark .current-item-mark)
  +                   (current-item-mark .current-item-mark)
                      (sub-window .sub-window)) menu
       ;; return as string
       (format nil "~A~A~A"
  
positive.code: 
  (defmethod draw-menu ((menu menu-window))
    (with-accessors ((layout .layout) (scrolled-layout .scrolled-layout) (scrolled-region-start .scrolled-region-start)
                     (title .title) (border .border) (len .max-item-length) (sub-win .sub-window)) menu
      (clear sub-win)
      (let ((m  (car  layout))
            (n  (cadr layout))
  
negative.code:             ;; for the current item, draw the current-item-mark
              ;; for all other items, draw a space
              (if (= current-item-number item-number)
                  current-item-mark
                  (make-string (length current-item-mark) :initial-element #\space))
              ;; then add the item
              (let ((item (nth item-number items)))
                (typecase item
  