gistfile1.clj

(ns groupon.core
    (require [clojure.string :refer [lower-case]]))

;;functional code

(defn delete-item [items n]
      (vec (concat (take n items) (drop (inc n) items))))

(def commands [{:name "(A)dd"
                :key :a
                :needs [:text]
                :function conj}
               {:name "(E)dit"
                :key :e
                :needs [:index :text]
                :function assoc}
               {:name "(D)elete"
                :key :d
                :needs [:index]
                :function delete-item}
               {:name "(S)ort"
                :key :s
                :needs []
                :function sort}
               {:name "(R)everse"
                :key :r
                :needs []
                :function reverse}
               {:name "(Q)uit"}])

;;imperative code

(defn input []
      (flush)
      (read))

(defn get-text []
      (print "New text:")
      (input))

(defn get-index []
      (println "Which item?")
      (dec (input)))

(defn main-loop [items]
      (dorun (map-indexed (fn [i item]
                              (println (inc i) item))
                          items))
      (apply println (map :name commands))
      (let [x (keyword (input))]
           (when-not (= :q x)
                     (recur (let [{:keys [needs function]} (first (filter #(= (:key %) x) commands))]
                                 (apply function
                                        items
                                        (for [need needs]
                                             (case need
                                                   :text (get-text)
                                                   :index (get-index)))))))))

(defn -main []
      (println "Welcome to List Keeper!")
      (main-loop []))