anchor.diff:    (declare (ignorable pane))
     (setf (gadget-value button :invoke-callback t) t))
   
  -(defmacro with-radio-box (&body body &rest options)
  +(defmacro with-radio-box (&rest options &body body)
     `(make-pane 'radio-box ,@options
   	      :current-selection (first ,body)
   	      ,@body))
  
positive.code:     (when armed
        (setf armed nil)
        (if (gadget-value pane)
  	  (push-highlight-button pane)
  	  (unhighlight-button pane))
        (disarmed-callback pane (gadget-client pane) (gadget-id pane)))))
  
  (defmethod handle-event ((pane toggle-button-pane) (event pointer-button-press-event))
  
negative.code:       (activate-callback pane (gadget-client pane) (gadget-id pane))
        (setf armed t)
        (setf (push-button-show-as-default-p pane) nil)
        (setf (gadget-current-color pane) (gadget-highlighted-color pane))
        (dispatch-repaint pane (sheet-region pane))
        (disarmed-callback pane (gadget-client pane) (gadget-id pane)))))
  
  (defmethod handle-event ((pane push-button-pane) (event window-repaint-event))
  