anchor.diff:                     (allocate-space child 
                                      width height)
                      )
  -                 (incf x major)))))))
  +                 (incf x major)
  +                 (incf x major-spacing)))))))
    
    (defclass xrack-pane (xbox-pane) ())
    
  
positive.code:    (compose-space (content-pane content)))
   
   (defmethod compose-space ((box xbox-pane))
     (with-slots (contents) box
       (loop
           for content in contents
           for sr = (content-sr* box content)
  
negative.code:          minimize (space-requirement-max-minor sr) into max-minor
           finally
             (return
               (space-requirement+*
                (make-space-requirement
                 :major major
                 :min-major (min min-major major)
                 :max-major (max max-major major)
                 :minor minor
                 :min-minor (min min-minor minor)
                 :max-minor (max max-minor minor))
                :min-major (* (1- (length contents)) major-spacing)
                :max-major (* (1- (length contents)) major-spacing)
                :major (* (1- (length contents)) major-spacing)
                :min-minor 0
                :max-minor 0
                :minor 0)))))
  
   (defmethod allocate-space-aux ((box xbox-pane) width height)
     (with-slots (contents major-spacing) box
       (let* ((content-srs (mapcar #'(lambda (c) (content-sr* box c)) contents))
              (allot       (mapcar #'ceiling (mapcar #'space-requirement-major content-srs)))
              (wanted      (reduce #'+ allot))
              (excess      (- major wanted
                              (* (1- (length contents)) major-spacing))))
         #+NIL
         (progn
           (format T "~&;; ALLOCATE-SPACE-AUX ~S~%" box)
  