anchor.diff:  (defclass oriented-gadget-mixin (oriented-gadget)
     ;; Try to be compatible with Lispworks' CLIM.
     ())
  +
  +
  +;; Labelled-gadget
  +
  +(defgeneric draw-label (gadget label x y))
   
   (defclass labelled-gadget ()
     ((label :initarg :label
  
positive.code: 		 :initarg :show-value-p
  		 :accessor gadget-show-value-p)))
  
  (defmethod initialize-instance :before ((pane slider-pane) &rest rest)
    (declare (ignore rest))
    (setf (slot-value pane 'orientation) :vertical))
  
  (defmethod drag-callback ((pane slider-pane) client gadget-id value)
    (declare (ignore client gadget-id))
    (when (slider-drag-callback pane)
  
negative.code: ;;; Oriented-gadget, labelled-gadget, range-gadget
  ;;;
  
  ;; Oriented-gadget
  
  (defclass oriented-gadget ()
    ((orientation :initarg :orientation
                  :reader gadget-orientation)))
  