为什么这种懒惰的序列不打印

Question

我无法弄清楚为什么这种懒惰的序列不打印。我已经看过这里的其他帖子(例如(，似乎没有什么是我想要的。这是代码段...

(defn exp [x n]
    (reduce * (repeat n x))
)
(defn primes
    ([] (primes 1 1))
    ([n m] (if (= n 1) (lazy-seq (cons (* (exp 7 n) (exp 11 m)) (primes (+ m 1) (1))))
        (lazy-seq (cons (* (exp 7 n) (exp 11 m)) (primes (- n 1) (+ m 1)))))
    )
)
(take 4 (primes))

任何帮助将不胜感激。谢谢！

Answer 1

这三个评论确实给出了答案。但实际上查看代码总是很好，因此有两种提供印刷输出的方法。

(defn exp [x n]
  (reduce * (repeat n x)))
(defn primes
  ([] (primes 1 1))
  ([n m] (if (= n 1)
           (lazy-seq (cons (* (exp 7 n) (exp 11 m)) (primes (+ m 1) 1)))
           (lazy-seq (cons (* (exp 7 n) (exp 11 m)) (primes (- n 1) (+ m 1)))))))
(defn x-1 []
  (doseq [prime (take 4 (primes 2 2))]
    (println prime)))
(defn x-2 []
  (->> (primes 2 2)
       (take 4)
       (apply println)))