anchor.diff:    (let ((day-names '("Monday" "Tuesday" "Wednesday"
                        "Thursday" "Friday" "Saturday" "Sunday")))
       (multiple-value-bind
  -        (second minute hour date month year day-of-week dst-p tz)
  +          (second minute hour date month year day-of-week dst-p tz)
           (get-decoded-time)
         (declare (ignore dst-p))
         (format nil "~a ~d/~2,'0d/~d ~2,'0d:~2,'0d:~2,'0d (GMT~@d)"
  
positive.code:   (cairo-stroke cr))
  
  (defun random-color ()
    (flet ((rand-val ()
                     (/ (float (random 100)) 100)))
      (list (rand-val) (rand-val) (rand-val))))
  
  (defun bounce-main ()
    (within-main-loop
     (let ((balls (loop repeat +num-balls+ collect (make-ball)))
           (window (make-instance 'gtk-window
                                  :type :toplevel
                                  :title "Bouncing Balls"))
  
negative.code:                                 :width-request +canvas-width+
                                  :height-request +canvas-height+))
           (box (gtk-box-new :vertical 2))
           (run-button (gtk-button-new-with-label "Start"))
           (add-button (gtk-button-new-with-label "Add")))
       (labels ((update (&optional widget)
                  (declare (ignore widget))
                  (dolist (ball balls) (update-ball ball))
                  (gtk-widget-queue-draw canvas)
                  t))
         (g-signal-connect window "destroy" (lambda (widget)
                                              (declare (ignore widget))
                                              (leave-gtk-main)))
         (g-signal-connect run-button "clicked"
                           (lambda (widget)
                             (declare (ignore widget))
                             (g-timeout-add (floor (* 1000 +time-step+))
                                            #'update)))
         (g-signal-connect add-button "clicked"
                           (lambda (widget)
                             (declare (ignore widget))
  