expression logging in clojure

formlog.clj

(ns formlog)

(declare *log*)

(defn make-log [] (ref []))

(defmacro logged [& forms]
  (let [form (gensym "form")]
    `(dosync
      ~@(map (fn [form]
	       `(do (alter *log* conj '~form)
		    ~form))
	    forms))))


(defn playlog [log]
  (dosync
   (last
    (for [form @log]
      (eval form)))))

(defmacro with-log [log-ref & body]
  `(binding [*log* ~log-ref]
     ~@body))

(defn run-test-1 []
  (let [counter (ref nil)
	log (make-log)]
    (with-log log
      (logged (ref-set counter 0))
      (logged (alter counter inc ))
      (logged (alter counter inc))
      (logged  (alter counter #(* % %))
	       (alter counter * 2)))
    (prn @counter)
    (prn @log)
    ;; alter counter outside with-log...
    (with-log log
      (dosync (alter counter dec)))
    (prn @counter)
    ;; ... is not registered in log
    (prn @log)))