anchor.diff:  ;;; 30.4.1 The concrete push-button Gadget
   
   (defclass push-button-pane  (push-button
  +                             labelled-gadget-mixin
                                changing-label-invokes-layout-protocol-mixin
                                arm/disarm-repaint-mixin
                                enter/exit-arms/disarms-mixin
  
positive.code:                      (setf (gadget-client c) pane)
                       c))
                   choices)))
      (mapc (curry #'sheet-adopt-child pane) children)
      (reorder-sheets pane children) ))
  
  ;;; ------------------------------------------------------------------------------------------
  ;;;  30.4.7 The concrete list-pane and option-pane Gadgets
  
negative.code: 
  (defclass labelled-gadget ()
    ((label       :initarg :label
                  :initform ""
                  :accessor gadget-label)
     #+NIL
     (align-x     :initarg :align-x
                  :accessor gadget-label-align-x)
     #+NIL
     (align-y     :initarg :align-y
                  :accessor gadget-label-align-y)
     #+NIL
     (text-style  :initform *default-text-style*
  		:initarg :text-style
                  :accessor gadget-text-style)))
  