不解释了，这么简单的题目。

(defn for-each[f item]
  (if (not (empty? item))
    ;(println (f (first item)))
    (f (first item))
   )
  (if (not (empty? item))
    (for-each f (rest item))
  )
  ;(f (first item))
  )

执行结果如下