A word-problem game from a swedish newpaper solved in clojure

svd.clj

(ns svd.core
  (:use 
    clojure.contrib.combinatorics)
  (:require
   [clojure.contrib.duck-streams :as ds]
   [clojure.contrib.str-utils :as str]))

(defn wordlist []
  (set (map #(re-find #"[^/]*" %) (ds/read-lines "sv_se.dic"))))

(defn get-all-words [letters required]
  (let [perms (map #(apply str %)
		   (filter #(contains? (into #{} %) required)
		      (mapcat permutations 
			      (mapcat #(combinations letters %) 
				      '(4 5 6 7 8 9)))))
	words (wordlist)]
    (filter #(contains? words %) perms)))

(defn main [letters required]
  (let [words (get-all-words 
	       (into #{} letters)
	       (. required charAt 0))]
    (println (str "Hittade " (count words) " ord."))
    (loop [n 1]
      (if (not (> n (count words)))
	(do
	  (println (str n ". " (nth (sort-by #(count %) words) (- n 1))))
	  (recur (+ n 1)))))))