(deftype SeqFly [s]
  clojure.lang.ISeq
    (first [this] (first (split s)))
    (next  [this] (SeqFly. (last (split s))))
    (more [this] (next this))
    (cons [this other] '())
    (equiv [this other] true)
  clojure.lang.Seqable 
    (seq [this] this)
  Object
    (toString [this] (str s)))