a lazy shuffle function in clojure; probably not original

lazy_shuffle.clj

(defn lazy-shuffle
  "Returns a locally-shuffled lazy seq from the given collection. The first
  arg has something to do with how it works so make sure it's a good one."
  [window-size coll]
  (let [[xs more] (split-at window-size coll)]
    ((fn self [v more]
       (lazy-seq
         (if (empty? more)
            v
            (let [[x & more] more
                  idx (rand-int window-size)]
              (cons (get v idx)
                    (self (assoc v idx x) more))))))
     (vec (shuffle xs))
     more)))
   
user> (take 100 (lazy-shuffle 10 (range)))
=> (7 0 8 6 2 9 11 1 10 5 16 4 13 12 22 20 17 26 18 14 27 29 21 15 32 23 35 24 33 34 25 28 30 40 36 19 37 45 31 43 3 38 49 39 51 50 44 46 42 57 53 47 52 59 48 56 55 63 41 64 66 67 5\
4 58 71 74 69 73 76 68 65 80 60 79 62 72 84 85 70 61 75 78 88 81 82 89 95 86 90 96 83 87 77 100 98 101 94 103 99 93)