sort.clj

(require '[clojure.string :as str])

(defn remove-punc [s]
  (clojure.string/replace s #"[.!?\\-]" ""))

(defn split-to-words [s]
  (clojure.string/split s #" "))

(defn sort-by-alpha [coll]
  (sort-by clojure.string/lower-case coll)) ; call lower-case in the comparator (x y)

(defn sort-words [s]
  (->> s
    remove-punc
    split-to-words
    sort-by-alpha
    vec))

(= (sort-words "Clojure is a fun language!") ["a" "Clojure" "fun" "is" "language"])