(define make-add (lambda (a) (lambda (b) (+ a b))))
(define add4 (make-add 4))
(add4 5)

`(a b ,((lambda (a) `(test . ,a)) 69) c d)

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define fib (lambda (c) (_fib 0 1 0 c)))
(define _fib (lambda (a b n c)
                  (if (= n c)
                      b
                      (_fib b (+ a b) (+ n 1) c))))





(define do (lambda (c f) (_do f '() 0 c)))

(define _do (lambda (f r n c)
                 (if (= n c) r
                     (_do f (cons (f n) r) (+ n 1) c))))

;; comment
;; another comment
;; fib(13)
;(do 10 (lambda (n) (display (fib n)))) ; comment

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(define +list (lambda (l) (_+list l 0)))
(define _+list (lambda (l acc)
                 (if (nil? l)
                     acc
                     (_+list (cdr l) (+ acc (car l))))))
(+list '(10 12))

(define * (lambda (a n) (+list (do n (lambda (n) a)))))

(* 9 7)

(define reverse (lambda (l) (_reverse l '())))
(define _reverse (lambda (l n)
                   (if (nil? l) n
                       (_reverse (cdr l) (cons (car l) n)))))

;; (+list (do 100 (lambda (n) (fib n))))
(reverse (do 100 (lambda (n) (fib n))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;; don't know about a good example
(defmacro m (a) `(+ ,a 57))
(m (+ 1 2))

(define cadr (lambda (l) (car (cdr l))))

(define map (lambda (fn list)
              (if (nil? list)
                  list
                  (cons (fn (car list)) (map fn (cdr list))))))

(map (lambda (n) (+ n 1)) '(1 2 3))

(defmacro let (vars body)
  `((lambda ,(map car vars) ,body) . ,(map cadr vars)))

(let ((a 8) (b 9)) (+ a b))