Data commit

Task/Detect-division-by-zero/Ol/detect-division-by-zero.ol

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+(define (safediv a b)
+   (if (eq? (type b) type-complex)
+      (/ a b) ; complex can't be 0
+      (let ((z (/ 1 (inexact b))))
+         (unless (or (equal? z +inf.0) (equal? z -inf.0))
+            (/ a b)))))
+
+; testing:
+(for-each (lambda (x)
+      (if x (print x) (print "division by zero detected")))
+   (list
+      (safediv 1 5)    ; => 1/5
+      (safediv 2 0)    ; => division by zero detected
+      (safediv 3 1+2i) ; => 3/5-6/5i
+      (safediv 4 0+i)  ; => 0-4i
+      (safediv 5 7/5)  ; => 25/7
+))