clojure.core/do

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Type: var Added: Clojure unknown Examples: 4 Runnable: 1

()

Evaluates the expressions in order and returns the value of the last. If no expressions are supplied, returns nil. See http://clojure.org/special_forms for more information.

Examples

by zk on 2010-10-25 . May have evaluation errors. ▶

;; do is used to evaluate multiple expressions in order, usually for the ;; purpose of evaluating exprs that have side-effects (such as printing ;; or I/O). do returns the value of its last expression. ;; ;; do w/o args returns nil. => (do (println "LOG: Computing...") (+ 1 1)) LOG: Computing... 2 => (do) nil

by rafmagana on 2015-05-29 . May have evaluation errors. ▶

;; `fn` (`defn` by extension) and `let` have an implicit `do` => ((fn [] (println "Something") ; printed in stdout (str "Return this"))) "Return this" => (defn do-example [] (println "Something") ; printed in stdout (str "Return this"))) => (do-example) "Return this" => (let [name "John"] (println "Something") ; printed in stdout (str "Hello " name)) "Hello John"

by ertugrulcetin on 2016-02-28 ▶

(if (> 2 1) (do (print "2 greater than 1") ; with 'do' you can extend if block true)) ;;=>"2 greater than 1" ;;=>true

by joncorr on 2017-07-16 . May have evaluation errors. ▶

;; Print the result of time without the output of (range 1000) => (do (time (range 1000)) nil)

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