Name: Anonymous 2011-12-23 12:06
Isn't
equivalent to...
(letrec ([is-even? (lambda (n)
(or (zero? n)
(is-odd? (sub1 n))))]
[is-odd? (lambda (n)
(and (not (zero? n))
(is-even? (sub1 n))))])
(is-odd? 11))equivalent to...
(let
([is-even? nil]
[is-odd? nil])
(set! is-even? (lambda (n)
(or (zero? n)
(is-odd? (sub1 n)))))
(set! is-odd? (lambda (n)
(and (not (zero? n))
(is-even? (sub1 n)))))
(is-odd? 11))