benefit_of_transducers.clj

;; without transducers

(defn notify [n]
  (println (str "Doing something to: " n))
  n)

(defn notify-and-add-up
  ([] 0)
  ([result] result)
  ([result input] (+ result (notify input)))
  ([result input & inputs]
    (+ result (apply notify input inputs))))

(reduce notify-and-add-up 0 '(1 2 3))


;; with transducers:

(defn notify [n]
  (println (str "Doing something to: " n))
  n)

(def notify-and-add-up ((map notify) +))

(reduce notify-and-add-up 0 '(1 2 3))