;; The hole a capture could otherwise be laundered through, and the reason
;; "the result of a call is clean" is a rule and not a hope.
;;
;; [sneak]'s literal captures [g], so its body holds a *copy* of a function
;; value that may itself carry an environment — and the copy is read out of an
;; environment, which is the one aggregate a function value is ever stored in.
;; If a copy read back out were treated as clean, the literal could return it,
;; the return would arrive at [sneak]'s caller as an ordinary call result, and
;; a capturing value would be out of the frame that owns it with nothing
;; having refused anything.
;;
;; So a function value read out of a struct, a case or a pointer is suspect,
;; and the refusal lands inside the lifted body where the return is written.
(defn getf [f (Fn [] (Fn [] i32))] (Fn [] i32) (f))

(defn sneak [g (Fn [] i32)] (Fn [] i32)
  (getf (fn [] g)))

(defn main [] i32 0)