(def reduce
     (fn (f xs initial-value)
         (cond
          ((first xs) (reduce f (rest xs) (f initial-value (first xs))))
          (true initial-value))))

(def map
     (fn (f xs)
         (reduce (fn (acc x) (cons acc (f x))) xs (list))))

;; Since SereneSimple only have List data structure and
;; it is effecient from the start. So the following function
;; will return (6 5 4 3 2)
(println (map (fn (x) (+ 1 x))
              (list 1 2 3 4 5)))


(println
 (reduce (fn (y x)
             (cons y (* x x)))
         (list 1 2 3 4)
         (list)))