search-tree?.clj

(do (defn search-tree?* [tree]
      (if (coll? tree)
        (let [[root-node left-node right-node] (concat tree (cycle [nil]))]
          (fn [] (and (->> [left-node root-node right-node]
                           (map #(if (coll? %) (first %) %))
                           (filter identity)
                           (apply <))
                      (search-tree?* left-node)
                      (search-tree?* right-node))))
        true))
    (def search-tree? (partial trampoline search-tree?*))
    (search-tree? [3 [1 0 2] [4 nil [6 5]]])) ;; => true