Nasty WIP thing that will take two sequences and return a list of actions that will transform the first sequence into the second one.

nasty-diff.clj

(defn diff-sorted
  [old new]
  ;;iterate through new list
  (let [old-set (set old)]
    (loop [actions '()
          old-list old
          new-list new]
     (let [old-val (first old-list)
           new-val (first new-list)
           rest-old (rest old-list)
           rest-new (rest new-list)]
       (cond
         (empty? new-list) actions
         (= old-val new-val) (recur (cons "nothing" actions) rest-old rest-new)
         (contains? old-set new-val) (recur (cons "move" actions) rest-old rest-new)
         :else (recur (cons "add" actions) rest-old rest-new))))))
;;currently does not return delete actions - should be easy if order of actions doesn't matter
(diff-sorted [:a :b :c] [:a :b :c])
(diff-sorted '(1 2 3) '(2 3 4))
(diff-sorted [1 2 3] [2 3 4])
(diff-sorted [1 2 3] [2 3 4 5 6])