编辑“︁Clojure”︁（章节）

===REPL编程===
与其他[[Lisp]]一样，Clojure的标志性特征之一是基于[[REPL]]的交互式编程。<ref>{{cite web |url=https://clojure.org/guides/repl/introduction |website=Clojure.org |title=Programming at the REPL: Introduction |access-date=2018-12-04 |archive-date=2018-12-04 |archive-url=https://web.archive.org/web/20181204134219/https://clojure.org/guides/repl/introduction |dead-url=no }}</ref>在以下示例中，<code>;;</code>表示一行注释的开始，而<code>;; =></code>则表示输出：

<syntaxhighlight lang="clojure">
;; 定义一个var
(def a 42)
;; => #'user/a

;; 调用名为`+`的函数
(+ a 8)
;; => 50

;; 调用名为`even?`的函数
(even? a)
;; => true

;; 定义一个函数以返回n除10之余
(defn foo [n] (rem n 10))
;; => #'user/foo

;; 调用该函数
(foo a)
;; => 2

;; 打印`rem`的文档字符串（docstring）
(doc rem)
;; =>
-------------------------
clojure.core/rem
([num div])
 remainder of dividing numerator by denominator.

;; 打印`rem`的源代码
(source rem)
;; =>
(defn rem
  "remainder of dividing numerator by denominator."
  {:added "1.0"
   :static true
   :inline (fn [x y] `(. clojure.lang.Numbers (remainder ~x ~y)))}
  [num div]
    (. clojure.lang.Numbers (remainder num div)))
</syntaxhighlight>