(+ 2 3)
(* 2 3)
(+ 2 3 4 5)
(* 2 3 4 5)
(< 2 3)
(< 3 3)
(< 4 3)
null
()
(cons 1 null)
(define L (cons 1 (cons 2 (cons 3 (cons 4 null)))))
(null? L)
(null? null)
(first L)
(rest L)
(first (rest L))
(first (rest (rest L)))
(first (rest (rest (rest L))))
(define M (cons (cons 1 (cons 2 null)) (cons 3 (cons 4 null))))
(first M)
(rest M)
(first (first M))
((lambda(x) x) 99)
((lambda(x) (* x x)) 99)
(((lambda(x) (lambda(y) (* x y))) 3) 4)
(let ((x 99)) x)
(let () 5)
(let ((x 99) (y 100)) (* x y))
(let ((x 99) (y 100) (z 101)) (* (+ x z) y))
(let ((x 99)) (let ((y 101)) (+ x y)))
(let ((x 99)) (let ((x (+ x 1))) x))
(let ((x 2)) (let ((y 3)) (let ((z 4)) (+ x y z))))