;;;; (clone xs) on a slice: the elements copied into a block from the context
;;;; allocator, or from one named, and answered as a slice over it. Writing
;;;; through the copy leaves the original alone, and the other way round.
(defstruct P [x i32 y f64])

(defn show [xs [i32]] ()
  (dotimes [i (length xs)]
    (print (at xs i))
    (print " "))
  (println ""))

(defn main [] i32
  (let [arr [1 2 3 4 5]
        c (clone (slice arr 1 4))]
    (set (at c 0) 20)
    (set (at arr 2) 30)
    (show c)
    (show (slice arr)))
  ;; From a Vec's view, into a named arena; wider elements than a byte.
  (let [a (arena-new 1024)
        v (vec-new P)]
    (push v (P {.x 1 .y 1.5}))
    (push v (P {.x 2 .y 2.5}))
    (let [c (clone (slice v) a)]
      (set (.x (at v 0)) 9)
      (println (.x (at c 0)) (.y (at c 1)) (length c))))
  ;; An empty slice clones to an empty slice.
  (let [e (clone (slice (bytes-view "abc") 1 1))]
    (println (length e)))
  0)