multiplex.cljs

(defn put-all! [cs x]
  (doseq [c cs]
    (put! c x)))

(defn multiplex [in cs-or-n]
  (let [cs (if (number? cs-or-n)
             (repeatedly cs-or-n chan)
             cs-or-n)]
    (go (loop []
          (let [x (<! in)]
            (if-not (nil? x)
              (do
                (put-all! cs x)
                (recur))
              :done))))
    cs))