;;;; type-of: every value's kind as a keyword, and a class instance's class
;;;; name, which is what class-of answers for it.

(defclass point [x y])

;; A defmulti over type-of is dispatch on the kind of the first argument.
(defmulti describe [v] dyn (type-of v))
(defmethod describe :int [v] "a whole number")
(defmethod describe :text [v] "some text")
(defmethod describe :point [v] "a point")
(defmethod describe :else [v] "something else")

(defn main [] i32
  (let [n (the i32 7)
        f (the f32 1.5)
        b (the bool true)
        s (the string "typed")]
    (println (type-of nil))
    (println (type-of true))
    (println (type-of 42))
    (println (type-of 2.5))
    (println (type-of "hello"))
    (println (type-of [1 2 3]))
    (println (type-of {:a 1}))
    (println (type-of :k))
    (println (type-of (point 1 2)))
    ;; Typed values cross into dyn first and answer the kind they become.
    (println (type-of n))
    (println (type-of f))
    (println (type-of b))
    (println (type-of s))
    (println (describe 3))
    (println (describe "x"))
    (println (describe (point 3 4)))
    (println (describe [1]))
    (if (= (type-of (point 0 0)) (class-of (point 0 0))) 0 1)))