(defstruct Enemy [hp i32  name string])

(defvar spawned i32)
(defconst room-size 4)
(defvar room [room-size i32])

;; `set` takes a fixed list of forms, not an extensible setf.
(defn main [] ()
  (let [e (Enemy {.hp 10 .name "slime"})
        p (addr e)]
    (set spawned (+ spawned 1))    ; a local or a defvar
    (set (.hp e) 7)                ; a struct field
    (set (.hp p) 8)                ; through a (Ptr Enemy) — derefs one level
    (set (at room 2) 5)            ; a fixed array or slice element
    (set (deref p) (Enemy {.hp 3 .name "wisp"}))   ; a whole-object store

    (print (.hp e)) (println "")
    (println (.name e))
    (print (at room 2)) (println "")
    (print spawned) (println "")))