gistfile1.clj

(defn timeout-line-seq
  "Takes a reader, and returns a line-seq that can time out on reading the next line."
  [^Reader reader timeout]
  (let [q (LinkedBlockingQueue. 10)
        q-seq (fn this []
                (lazy-seq
                  (if-let [l (.poll q timeout TimeUnit/MILLISECONDS)]
                    (when-not (= ::end l)
                      (cons l (this)))
                    (do
                      (.close reader)
                      (throw (TimeoutException. "next-line timeout elapsed"))))))]
    (future
      (try
        (doseq [l (line-seq reader)]
          (.put q l))
        (finally
          (.put q ::end))))
    (q-seq)))