Clojure rand nth在编译后总是产生相同的结果
我已经使用core.clj通过Leiningen创建了一个项目:Clojure rand nth在编译后总是产生相同的结果,clojure,Clojure,我已经使用core.clj通过Leiningen创建了一个项目: (ns cotd.core (:gen-class) (:use [clojure.repl :only (doc)])) (defmacro eval-doc [form] (let [resulting-symbol (eval form)] `(doc ~resulting-symbol))) (defn- random-function-name [] (rand-nth (keys (ns
(ns cotd.core
(:gen-class)
(:use [clojure.repl :only (doc)]))
(defmacro eval-doc
[form]
(let [resulting-symbol (eval form)]
`(doc ~resulting-symbol)))
(defn- random-function-name []
(rand-nth (keys (ns-publics 'clojure.core))))
(defn -main
"Display random doc page"
[& args]
(eval-doc (random-function-name)))
在编译和运行之后,它始终会产生相同的结果:
$ java -jar cotd.jar
-------------------------
clojure.core/unchecked-negate
([x])
Returns the negation of x, a long.
Note - uses a primitive operator subject to overflow.
$ java -jar cotd.jar
-------------------------
clojure.core/unchecked-negate
([x])
Returns the negation of x, a long.
Note - uses a primitive operator subject to overflow.
但在连续两次通话中:
(do
(eval-doc (random-function-name))
(eval-doc (random-function-name))))
它在一次“调用”中产生两个不同的结果
我尝试过的是谷歌搜索、阅读等,但我不知道发生了什么
如何动态调用此rand n?问题不在于rand n,而是因为let语句中的结果符号是在编译阶段生成的@贝亚莫在这里给出了答案: