tarcieri-4clojure-solution28.clj

;; tarcieri's solution to Flatten a Sequence
;; https://4clojure.com/problem/28

(fn zomgflatten
  ([input]
    (seq (zomgflatten input [])))
  ([seq output]
    (let [head (first seq) tail (rest seq)]
      (if head
        (if (or (list? head) (vector? head))
          (let [res (zomgflatten head output)]
            (recur tail res))
          (let [res (conj output head)]
            (recur tail res)))
        output))))