Clojure tree walker

walker.clj

(defn tree-searcher
  "Parse through every node in a tree and check against
give matcher function. If a match succeeds, return the node.
If no match is found after all recursions, just return the tree.
Also see clojure.walk"
  [zipper matcher]
  (loop [loc zipper]
    (if (zip/end? loc)
      (zip/root loc)
      (if-let [matcher-result (matcher (zip/node loc))]
        (matcher-result)
        (recur (zip/next loc))))))