;;;; The reload primitive's fixture, v1 (NEXT.md, dev loop step 1 and 2).
;;;;
;;;; There is deliberately no [main]: the host is reload_host.c, which links
;;;; this program and then dlopens two rebuilt copies of [bump].
;;;;
;;;; [counter] is the state that has to survive a reload — a redefinition
;;;; module declares it [external], so the loaded object writes the host's copy
;;;; and not a new one. [outer] is the call site that has to *follow* a reload:
;;;; it is compiled once, into the host, and never rebuilt, so if a redefined
;;;; [bump] runs when the host calls [outer] then the cell is doing its job.
;;;; The string is not decoration either — a redefinition module has to carry
;;;; its own constants, and a one-function module usually has none.
(defvar counter i64)

;;; Unused, and that is the point: the session's compatibility rules only get a
;;; chance to speak about a change the *checker* accepts, and retyping a var
;;; something else reads is an ordinary type error long before it is a layout
;;; question.
(defvar spare i64)

(defn helper [x i64] i64 (* x 2))

(defn bump [] i64
  (print-line "v1")
  (set counter (+ counter 1))
  (helper counter))

(defn outer [] i64 (bump))