Bug fix.

[haidongZhang]

01-begin中335行使用lambda时是否多了一层括号？无法正确执行。

(require 2htdp/universe)
(animate (#,(hl (lambda (x)))
(place-image (my-star (+ x 2)) 75 75 (empty-scene 150 150))))

[tyrchen]

My fault. Cold shoul look like this:

(animate (lambda (x)
           (place-image (my-star (+ x 2)) 75 75 (empty-scene 150 150))))