benchmark code

gistfile1.clj

(ns x
  (:use [criterium.core]))

(defn pre-into [c i]
  (into [i] c))

(defn dl
  "Return a difference list for a list"
  [l]
  (fn [x] (concat l x)))

; Return an empty difference list
(def dlempty identity)

(defn undl
  "Return a list for a difference list (just call the difference list with nil)"
  [aDl]
  (aDl nil))

(defn dlcons
  "Cons an item onto a difference list"
  [item aDl]
  (fn [x] (cons item (aDl x))))

(defn dlappend
  "Append two difference lists"
  [dl1 dl2]
  (fn [x] (dl1 (dl2 x))))

(defn pre-dl [c i]
  (dlappend (dl (list i)) c))

(defn do-test [init f post]
  (doall (post (reduce f init (range 1000)))))

(defn test []
  (with-progress-reporting (bench (do-test [] pre-into identity)))
  (with-progress-reporting (bench (do-test (dl '()) pre-dl undl))))