;;;; Value semantics, spec-memory.md. Not covered by calc-me, and the property
;;;; most likely to be silently wrong in a backend: a struct or a fixed array
;;;; copies on assignment, a slice copies only its view.
(defstruct P [x i32])
(defvar arr [3 i32])

(defn main [] i32
  (let [a (P {:x 1})]
    (let [b a]                                ; a copy, not an alias
      (set (.x a) 99)
      (print (.x b)) (println "")))           ; 1

  (set (at arr 0) 5)
  (let [c arr]                                ; fixed arrays are values too
    (set (at arr 0) 77)
    (print (at c 0)) (println ""))            ; 5

  (let [s (bytes "hello")]
    (let [v (slice s 1 3)]                    ; a view into the same bytes
      (print v) (println "")))                ; el
  0)