clojure.core/println

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Type: function Added: Clojure 1.0 Examples: 2 Runnable: 1

([& more])

Same as print followed by (newline)

Examples

by devn on 2010-08-02 . May have evaluation errors. ▶

(println "Hello world.") Hello world. nil (def items [ "hello" :a 1 (list :b 2) \c {:d 4} #{5 6 7} ]) #'user/items ; println is for human-readable output, like a report. Note the lack of quotes around the string "hello" and the unescaped letter "c". (println items) [hello :a 1 (:b 2) c {:d 4} #{5 6 7}] nil ; prn outputs items in a machine-readable format, such as in a source ; file. Note the double-quotes around the string "hello" and the escaped letter "c". (prn items) ["hello" :a 1 (:b 2) \c {:d 4} #{5 6 7}] nil ; pr-str produces a string with escaped punctuation, so that println yields the same result as the original prn call. (println (pr-str items)) ["hello" :a 1 (:b 2) \c {:d 4} #{5 6 7}] nil ; Calling println w/o args outputs a newline and nothing else. (println) nil ; The newline function does the same. (newline) nil

by rsachdeva on 2014-10-20 ▶

; be careful when using println in functions like map ; println has nil as its return value (map #(println %) (range 1 4)) (1 2 3 nil nil nil)

See also

• clojure.core/prn
• clojure.core/print (1)
• clojure.core/println-str
• clojure.pprint/pprint (0)

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