rendezvous with cassidoo challenge: 22.10.10

truncate.clj

(ns truncate
  (:require [clojure.test :refer [deftest is]))

(defn truncate [s n]                                                                             
  (let [tokens (re-seq #"\W+|_|[a-zA-Z]+" s)                                                     
        word?  #(re-find #"\w+" %)                                                               
        truncate-w (fn [token]                                                                   
                     (if (and (word? token)                                                      
                              (> (count token) n))                                               
                       (subs token 0 n)                                                          
                       token))                                                                   
        truncated (map truncate-w tokens)]                                                       
    (apply str truncated)))
                                                                                                 
(deftest truncate-test                                                                           
  (let [n 3]                                                                                     
    (is (= "nev gon giv you up" (truncate "never gonna give you up" n)))                         
    (is (= "*hel* dar, my ~old_fri" (truncate "*hello* darkness, my ~old_friend" n)))))