clojure.core/future-cancel

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Type: function Added: Clojure 1.1 Examples: 3 Runnable: 0

([f])

Cancels the future, if possible.

Examples

by BertrandDechoux on 2012-06-09 . May have evaluation errors. ▶

(def f (future (Thread/sleep 5000) (inc 0))) #'user/f (future-cancel f) true (future-cancelled? f) true

by BertrandDechoux on 2012-06-09 . May have evaluation errors. ▶

(def f (future (inc 0))) #'user/f (future-cancel f) false (future-cancelled? f) false

by jimka2001 on 2025-06-15 . May have evaluation errors. ▶

;; Inside the future, you can detect that a call to `future-cancel` ;; was made from outside. This idiom should allow you to clean up ;; temp files, kill sub-futures etc. (let [f (future (try (doseq [r (range)] (Thread/sleep 1000)) (catch InterruptedException e (println (str "caught exception: " (.getMessage e))))))] (Thread/sleep 3000) (future-cancel f))

See also

• clojure.core/future (1)
• clojure.core/future?
• clojure.core/future-cancelled? (0)
• clojure.core/future-done? (1)

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