diff options
Diffstat (limited to 'coding-exercises/2/83/install-rational.rkt')
| -rw-r--r-- | coding-exercises/2/83/install-rational.rkt | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/coding-exercises/2/83/install-rational.rkt b/coding-exercises/2/83/install-rational.rkt index d1c94fc..334f802 100644 --- a/coding-exercises/2/83/install-rational.rkt +++ b/coding-exercises/2/83/install-rational.rkt @@ -69,8 +69,20 @@ (let ((g (gcd n d))) (cons (sign (/ n g)) (abs (/ d g))))) + (define (dropme rat) + (display (list (numer rat) (denom rat))) + (display (list (integer? (numer rat)) (integer? (denom rat)))) + (if (and (integer? (numer rat)) + (integer? (denom rat))) + ((get 'make 'integer) (/ (numer rat) (denom rat))) + (list 'undefined))) (define (raiseme rat) - ((get 'make 'real) (/ (numer rat) (denom rat)))) + (display (list (numer rat) (denom rat))) + (display (list (integer? (numer rat)) (integer? (denom rat)))) + (if (and (integer? (numer rat)) + (integer? (denom rat))) + ((get 'make 'real) (/ (numer rat) (denom rat))) + (list 'undefined))) ;; constructor (put 'make 'rational @@ -89,8 +101,7 @@ (put 'div '(rational rational) (lambda (x y) (tagme (div-rat x y)))) (put 'raise '(rational) raiseme) - (put 'project '(rational) (lambda (rat) - ((get 'make 'integer) (/ (numer rat) (denom rat))))) + (put 'project '(rational) dropme) ;; sqrt and trig methods for complex nums (put 'sqr '(rational) (lambda (r) (sqr (raiseme r)))) (put 'sqrt '(rational) (lambda (r) (sqrt (raiseme r)))) |