[x] (prn [:pre x]) x)) (xf/take-last 3) (map (fn [x] (prn [:post x]) x)))) (+ x y)) (redue add 0 (range 5)) ;; [:pre {:x 0, :y 0}] ;; [:pre {:x 0, :y 1}] ;; [:pre {:x 1, :y 2}] ;; [:pre {:x 3, :y 3}] ;; [:pre {:x 6, :y 4}] ;=> 10 (pm/logs) ;; [:post {:x 1, :y 2}] ;; [:post {:x 3, :y 3}] ;; [:post {:x 6, :y 4}] ;=> {:add [{:x 1, :y 2} {:x 3, :y 3} {:x 6, :y 4}]} (pm/logs) ;=> {:add [{:x 1, :y 2} {:x 3, :y 3} {:x 6, :y 4}]}