;Excerse 2.20
(define (same-parity first-value . other-values)
    (let ((match-parity (lambda (a b) (equal? (even? a) (even? b)))))
    (if (null? other-values) '()
      (if (match-parity first-value (car other-values))
        (cons (car other-values) (same-parity first-value (cdr other-values))
        (same-parity first-value other-values)))))

is giving me a bunch of weird errors about trying to use lists as integers in the match-parity helper function. I guess this is more of a misunderstanding of the implementation of lists in Scheme than the list concept, but in 2.2 those are mostly equivalent. Help?