1 (show-mob (make-mob :x 0 :y 0 :image (filled-rect 5 420) :tags '(wall)
2 :logic (cond ((key 'up) (incf x 5))
3 ((key 'down) (decf x 5)))))
5 (show-mob (make-mob :x 635 :y 0 :image (filled-rect 5 420) :tags '(wall)
6 :logic (cond ((key 'up) (decf x 5))
7 ((key 'down) (incf x 5)))))
9 (let ((xvel 100) (yvel 0))
10 (show-mob (make-mob :x 300 :y 200 :image (filled-circle 7)
12 (cond ((key 'plus) (if (> xvel 0) (incf xvel 10) (decf xvel 10)))
13 ((key 'minus) (if (> xvel 0) (decf xvel 10) (incf xvel 10))))
14 (cond ((collision '(wall)) (setq xvel (neg xvel))))
15 (movement :xvel xvel :yvel yvel)))))