gistfile1.txt

;;https://github.com/naleksander/instrumentos/blob/master/src/instrumentos/yield.clj

(defn funnel []
  (let [q (java.util.concurrent.SynchronousQueue.)]
    [(take-while (partial not= q) 
		 (repeatedly #(.take q)))
     (fn
       ([e] (.put q e)) 
	([] (.put q q)))]))

(defmacro bound-future[& body]
  `(future-call (bound-fn [] ~@body)))

(declare yield)

(defmacro yieldish[& content]
  `(let[[s# f#] (funnel)]
     (binding [yield f#]
       (bound-future (do ~@content (yield))) s#)))

(def fibs
     (yieldish
      (loop [a 0 b 1]
	(yield a)
	(recur b (+ a b)))))

user> (take 10 fibs)
(0 1 1 2 3 5 8 13 21 34)