SICP Exercise 2.4
Using applicative-order evaluation on car
:
(car (cons x y))
(car (lambda (m) (m x y)))
((lambda (m) (m x y)) (lambda (p q) p))
((lambda (p q) p) x y)
x
Similarly, cdr
is:
(define (cdr z)
(z (lambda (p q) q)))
Using applicative-order evaluation on car
:
(car (cons x y))
(car (lambda (m) (m x y)))
((lambda (m) (m x y)) (lambda (p q) p))
((lambda (p q) p) x y)
x
Similarly, cdr
is:
(define (cdr z)
(z (lambda (p q) q)))