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;;;; Under Creative Commons Attribution-ShareAlike 4.0
;;;; International. See
;;;; <https://creativecommons.org/licenses/by-sa/4.0/>.
(define-module (net ricketyspace sicp two one)
#:export (make-rat))
(define (gcd a b)
(if (= b 0)
a
(gcd b (remainder a b))))
(define (make-numer n neg?)
(if neg? (* -1 (abs n))
(abs n)))
(define (make-denom d) (abs d))
(define (make-rat n d)
(let ((g (abs (gcd n d)))
(neg? (< (* n d) 0)))
(cons (/ (make-numer n neg?) g)
(/ (make-denom d) g))))
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