ll.clj

(definterface INode
  (getCar [])
  (getCdr [])
  (setCar [x])
  (setCdr [x])
  (valAt [i]))

(deftype Node [^:volatile-mutable car ^:volatile-mutable cdr]
  INode
  (getCar [_] car)
  (getCdr [_] cdr)
  (setCar [this x] (set! car x) this)
  (setCdr [this x] (set! cdr x) this)
  (valAt [this index] (loop [i index cursor this]
                         (if (zero? i)
                           cursor
                           (recur (dec i) (.cdr cursor))))))

(defn new-node [car & [cdr]]
  (Node. car cdr))

(defn list-reverse [nodes]
  (loop [cur nodes more (.getCdr nodes) reversed nil]
    (if-not cur
      reversed
      (recur more (if more (.getCdr more)) (do (.setCdr cur reversed) cur)))))

(defn list-eval [l]
  (loop [cur (first l) more (next l) nodes nil]
      (if-not cur
        (list-reverse nodes)
        (recur (first more) (next more) (new-node cur nodes)))))

(.getCar (list-reverse (list-eval '(1 2 3 4))))
(.. (list-eval '(1 2 3 4)) (valAt 0) getCar)