Exercism: "Hexadecimal in Clojure"

I solved the Hexadecimal problem in Clojure.

As usual I extracted some helpers and played with partial and the thread last macro (->>) to try to make the solution more readable:

	(ns hexadecimal
	(:require [clojure.string :as str]))
	(def ^:private ints-by-hex-digit
	(zipmap ["0" "1" "2" "3" "4" "5" "6" "7" "8" "9" "a" "b" "c" "d" "e" "f"]
	[0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15]))
	(defn- hex-digits [hex]
	(drop 1 (str/split (str/lower-case hex) #"")))
	(def ^:private hex-digit->int-digit
	(partial get ints-by-hex-digit))
	(defn- valid-hex? [hex-digits]
	(every? (complement nil?)
	(map hex-digit->int-digit hex-digits)))
	(defn- pow [base exp]
	(reduce * (repeat exp base)))
	(defn- hex-in-position->int
	[position hex-digit]
	(* (hex-digit->int-digit hex-digit)
	(pow 16 position)))
	(defn- reversed-hex-digits->int
	[reversed-hex-digits]
	(if (valid-hex? reversed-hex-digits)
	(reduce + (map-indexed hex-in-position->int
	reversed-hex-digits))
	0))
	(defn hex-to-int [hex]
	(->> hex
	hex-digits
	reverse
	reversed-hex-digits->int))

view raw hexadecimal.clj hosted with ❤ by GitHub

You can nitpick my solution here and/or see all the exercises I've done so far in this repository.