macros to stop a loop and timeouts in core.async

sandbox.clj

(require '[clojure.core.async :as async :refer :all])

(defmacro sleep
  ([ms stop-channel]
     `(alts! [(timeout ~ms) ~stop-channel]))
  ([ms]
      `(<! (timeout ~ms))))

(defmacro go-loop [bindings & body]
  (let [stop (first bindings)]
    `(let [~stop (chan)]
       (go (while (alt! ~stop false :default :keep-going)
             ~@body))
       ~stop)))

(defn hello-world [x]
  (go-loop [stop-timeout]
           (println "Hello World!")
           (sleep x stop-timeout)
           (println "I'm done sleeping, going to recur now...")))


;; user> (def q (hello-world 10000))
;; #'user/q
;; Hello World!
;; I'm done sleeping, going to recur now...
;; Hello World!
;; user> (close! q)
;; I'm done sleeping, going to recur now...
;; nil)