gistfile1.clj

(defn find-units
   [game pred]
   (let [units (vals (:units game))
	 _ (utils/trace "find-units on" (count units))
	 units  (filter (fn [u]
			  (println "bla!!!!!!!!!!!!!!")
			  (utils/trace "find-units" "testing unit:" (:id @u))
			  (if (and utils/*trace* (pred @u))
			    (utils/trace "find-units" "testing unit:" (:id @u) "positive!")
			    (utils/trace "find-units" "testing unit:" (:id @u) "negativ!"))
			  (pred @u)) units)]
   (println "Woggle woggel.")
   units))

;=> Trace<find-units on>: 2
;=> Woggle woggel.