     ;;; Draw a circle in the window and then respond to mouse clicks.
     ;;;
     ;;;  button1 - move circle to button location.
     ;;;  button3 - exit.
     ;;;  
     ;;;To call use >ezd -i
     ;;;            > (load "circle")
     ;;;            > (circle)
     ;;;            > (ezd '(pause)) ;causes Scheme  interpreter  to 
     ;;;                             ;wait for ezd completion

     (define (CIRCLE)

         (define (MOVE-C)
              (ezd `(object circle (fill-arc ,(- *mouse-window-x* 10)
                              ,(- *mouse-window-y* 10) 20 20 0 360))))

         (ezd '(window circle 300 300 "Circle")
           '(set-drawing circle)
           '(overlay circle circle)
           '(object background (fill-rectangle 0 0 300 300 clear))
           '(object circle (fill-arc 100 100 20 20 0 360))
           `(click background 1 ,move-c)
           '(click * 3 (begin (display 'stop-circle) (ezd '(quit)))))
)

