anchor.diff:  
   (defmacro define-slider-callback (name position)
     `(defun ,(make-symbol name) (gadget value)
  -     (let ((colored (find-if (lambda (x) (typep x 'climi::slider-test-pane))
  -                             (sheet-siblings gadget))))
  -       (setf ,(case position
  -		(1 `(car *rgb*))
  -		(2 `(cadr *rgb*))
  -		(3 `(caddr *rgb*)))
  -	     (/ value 10000)
  -	     (clim-internals::gadget-current-color colored)
  -	     (apply #'clim-internals::make-named-color "our-color"
  -		    (mapcar #'(lambda (color) (coerce color 'single-float))
  -			    *rgb*))))))
  +     (declare (ignore gadget))
  +     (setf ,(case position
  +              (1 `(car *rgb*))
  +              (2 `(cadr *rgb*))
  +              (3 `(caddr *rgb*)))
  +           (/ value 10000))
  +     (execute-frame-command *application-frame*
  +                            (list 'com-change-color
  +                                  (apply #'clim:make-rgb-color
  +                                         (mapcar #'(lambda (color) (coerce color 'single-float))
  +                                                 *rgb*))))))
   
   (defvar callback-red (define-slider-callback "SLIDER-R" 1))
   (defvar callback-green (define-slider-callback "SLIDER-G" 2))
  
positive.code: ;;; Free Software Foundation, Inc., 59 Temple Place - Suite 330, 
  ;;; Boston, MA  02111-1307  USA.
  
  (in-package #:clim-internals)
  
  ;;; Example gadget definition.
  (defclass slider-test-pane (basic-gadget) ())
  
  (defmethod handle-repaint ((pane slider-test-pane) region)
    (declare (ignore region))
    (multiple-value-bind (x1 y1 x2 y2) (bounding-rectangle* (sheet-region pane))
      (display-gadget-background pane
  			       (gadget-current-color pane)
  			       0 0
  			       (- x2 x1) (- y2 y1))))
  
  (in-package :clim-demo)
  
  ;;; Slider callback and macro.
  
  
negative.code: 
  (defun colorslider ()
    (run-frame-top-level (make-application-frame 'colorslider)))
  
  (define-application-frame colorslider
      () ()
  