Scheme: redefining built-ins

I'm having trouble with functions that are n-ary, for example, =, <, etc. I'm trying to implement = first of all. All I have is the following (it's n开发者_如何学运维ot very much).

(define builtin-= =)
(define (b= x y) (builtin-= x y))

(define (= . z)
 (if (null? z) #f
  (b= (car z) (apply = (cdr z)))))

However, this results in either infinite recursion or heap overflow when I run (= 2 3) or any other similar call.

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Thanks.

I figured it out.

(define builtin-= =)
(define (b= x y) (builtin-= x y))

(define (= . z)
  (if (or (null? z) (null? (cdr z)))
    #t
    (and (equal? (car z) (cadr z))
         (= (cdr z)))))

I have another problem though. I'm trying to do this for < also. So, equal? won't work.