partition-every.clj

(defn partition-every
  "adapted from clojure core version of partition-by
   partition a collection every time a predicate returns true
   => (partition-every keyword? [:a 1 2 3 :b :c 4 5 6 7 :d :e])
   ((:a 1 2 3) (:b) (:c 4 5 6 7) (:d) (:e))"
  [pred coll]
  (lazy-seq
    (when-let [s (seq coll)]
      (let [fst (first s)
            run (cons fst (take-while (complement pred) (next s)))]
        (cons run (partition-every pred (seq (drop (count run) s))))))))