;; -*- mode: lisp; -*-

(fn fact (n)
    (if (<= n 0)
        1
        (* n (fact (- n 1)))))

(assert (= (fact 12) 479001600))


(let ((square (fn (x) (* x x))))
  (assert (= (square 4) 16))
  )

(let ((x 42))
  (assert (= ((fn (y) (+ x y) 1)
              43)))
  )