exercise1_10_impl.clj

user> (defn f [n]
        (* 2 n))
#'user/f
user> (map f (range (inc 5)))
(0 2 4 6 8 10)
user> (require '[clojure.math.numeric-tower :refer [expt]])
nil
user> (defn g [n]
        (if (zero? n)
          0
          (expt 2 n)))
#'user/g
user> (map g (range (inc 5)))
(0 2 4 8 16 32)
user> (defn h [n]
        (case n
          0 0
          1 2
          (expt 2 (h (dec n)))))
#'user/h
user> (map h (range (inc 4)))
(0 2 4 16 65536)
user> (defn h' [n]  ; condpによる==比較版(任意の数値型に対応)
        (condp == n
          0 0
          1 2
          (expt 2 (h' (dec n)))))
#'user/h'
user> (map h' (range (inc 4)))
(0 2 4 16 65536)