(let defun (mac (name args body) 
  (list let name nil) 
  (list = name (list fun args body))))

(defun square (x) (* x x))

(let inc (mac (s) (list (q =) s (list (q +) s 1))))

(defun to-upper (str) (capture-upper (print str)))
(defun to-lower (str) (capture-lower (print str)))

(defun last (x) (if (cdr x) (last (cdr x)) (car x)))
(defun del-last (x) (if (cdr (cdr x)) (del-last (cdr x)) (setcdr x nil)))

(defun nth (a n) (if (is n 0) (car a) (nth (cdr a) (- n 1))))