(defn pls1 [x]
  (+ 1 x))

(defn pls2 [x]
  (+ 2 x))

(defn doit []
  (map (fn [i f]
         (f i))
       '(1 2 3 4 5)
       (cycle '(pls1 pls2))))
;produces (nil nil nil nil nil)

(defn doit []
  (map (fn [i f]
         (pls2 i))
       '(1 2 3 4 5)
       (cycle '(pls1 pls2))))
;produces (3 4 5 6 7)

(defn doit []
  (map (fn [i f]
         (+ 1 i))
       '(1 2 3 4 5)
       (cycle '(pls1 pls2))))
;produces (2 3 4 5 6)