suspendable_test.clj

(ns clojure.core.suspendable-test
  (:require [clojure.core.async :as async]))

(def c (async/chan))

(defn fn1 [ctrl-chan]
  (async/go-loop [cmd-old :run cmd-new :run]
    (condp = cmd-new
      :run (do
                 (when (not (= cmd-old cmd-new))
                   (println "SWITCH " cmd-old cmd-new))
                 (println "running...")
                 (let [[cmd _] (async/alts! [ctrl-chan (async/timeout 1000)])]
                   (recur :run (if (nil? cmd) :run cmd))))
      :suspend (do
                   (when (not (= cmd-old cmd-new))
                     (println "SWITCH " cmd-old cmd-new))
                   (println "suspended...")
                   (let [[cmd _] (async/alts! [ctrl-chan (async/timeout 3000)])]
                     (recur :suspend (if (nil? cmd) :suspend cmd))))
      :stop (println "stopped")
      (do
        (println "invalid command")
        (recur cmd-old cmd-old)))))