transient-perf-test.clj

(def & comp)
(def p partial)
(def $ apply)

(def kws (map (& keyword str) (seq "abcdefghijklmnopqrstuvwxyz")))
(defn items []
  (for [i (range 10000)]
    ($ merge (for [kw kws] {kw i}))))

(def head ($ merge (for [kw kws] {kw []})))
(time (doall ($ (p merge-with conj head)
                (items))))

(def t-head ($ merge (for [kw kws] {kw (transient [])})))
(time (doall ($ merge (map (fn [[k v]] {k (persistent! v)})
                           ($ (p merge-with conj! t-head)
                              (items))))))

;;-> Transient used by non-owner thread
;;    [Thrown class java.lang.IllegalAccessError]