(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-i64 (i64 (.hp e))) (newline)
    (print-line (.name e))
    (print-i64 (i64 (at room 2))) (newline)
    (print-i64 (i64 spawned)) (newline)))