Blocking queues to lazy seqs and vice versa

qseq.clj

(def ^:private poison (Object.))

(defn seq-to-qs
  "Place each element of the lazy seq in each of the queues, and finally the
   poison value."
  [s & qs]
  (doseq [e s q qs] (.put ^BlockingQueue q e))
  (doseq [q qs] (.put ^BlockingQueue q poison)))

(defn lazy-q-seq
  "Take a BlockingQueue and return a lazy sequence of its values. Stop when we
   hit the poison value."
  [^BlockingQueue q]
  (let [this (.take q)]
    (if-not (identical? this poison) 
      (lazy-seq (cons this (lazy-q-seq q))))))