;; A CFn is the bare address, so a literal written into one has nowhere to
;; keep the copies. Refused with the name of what it captured, because that is
;; the fact to act on, and with the fix named: widen the position to Fn, which
;; is what the type is for.
(defn apply-bare [f (CFn [i32] i32)  x i32] i32 (f x))

(defn main [] i32
  (let [bonus 10]
    (println (apply-bare (fn [x] (+ x bonus)) 5)))
  0)