Clojure 如何将算术添加到此函数？

我想要这个函数

(defn ret-lowest-str-len
    "Computes the lengths of two strings. Returns default length -- len -- 
     if len is <= the length of str-1 and len is <= length of str-2.

     Else, returns smaller of length of str-1 and str-2."

    [str-1 str-2 len]

    (let [l1 (count str-1)
          l2 (count str-2)]

        (if (and (<= len l1) (<= len l2))
            len
            (if (< l1 l2)
                l1
                l2))))

（定义最低结构长度）
“计算两个字符串的长度。返回默认长度--len--
如果lendefn有两个语法

(defn foo [] (expression) (expression))

及


一种常见的模式是让较小的arity版本填写默认值，并调用较高的arity情况：

(defn ret-lowest-str-len
([str-1 len] (ret-lowest-str-len str-1 "" len))
([str-1 str-2 len]
  (let [l1 (count str-1)
        l2 (count str-2)]
      (if (and (<= len l1) (<= len l2))
          len
          (if (< l1 l2)
              l1
              l2)))))

我将更进一步，使用可选参数列表的
&
语法，使其适用于任意数量的字符串，使用以下内容：

(defn lowest-str-len [default-len & strs]
    (let [lens (map count strs)]
        (apply min default-len lens)))

谢谢@Arthur。我去看看这个。效果很好@Arthur Ulfeldt。
user> (defn ret-lowest-str-len [& args] (reduce min (map count args)))
#'user/ret-lowest-str-len
user> (ret-lowest-str-len "a" "aaaa" "aaaaaaaaa")
1

(defn lowest-str-len [default-len & strs]
    (let [lens (map count strs)]
        (apply min default-len lens)))