Use Rat::gcd to make infix:<+>(Rat, Rat) and infix:<->(Rat, Rat) yiel…

…d Rats in more cases.
rakudo · Dec 3, 2009 · 7914ca3 · 7914ca3
1 parent 7ce13d8
commit 7914ca3
Showing 1 changed file with 6 additions and 4 deletions.
diff --git a/src/setting/Rat.pm b/src/setting/Rat.pm
@@ -55,8 +55,9 @@ class Rat {
 }
 
 multi sub infix:<+>(Rat $a, Rat $b) {
-    ($a.numerator * $b.denominator + $b.numerator * $a.denominator)
-        / ($a.denominator * $b.denominator);
+    my $gcd = Rat::gcd($a.denominator, $b.denominator);
+    ($a.numerator * ($b.denominator div $gcd) + $b.numerator * ($a.denominator div $gcd))
+        / (($a.denominator div $gcd) * $b.denominator);
 }
 
 multi sub infix:<+>(Rat $a, Int $b) {
@@ -68,8 +69,9 @@ multi sub infix:<+>(Int $a, Rat $b) {
 }
 
 multi sub infix:<->(Rat $a, Rat $b) {
-    ($a.numerator * $b.denominator - $b.numerator * $a.denominator)
-        / ($a.denominator * $b.denominator);
+    my $gcd = Rat::gcd($a.denominator, $b.denominator);
+    ($a.numerator * ($b.denominator div $gcd) - $b.numerator * ($a.denominator div $gcd))
+        / (($a.denominator div $gcd) * $b.denominator);
 }
 
 multi sub infix:<->(Rat $a, Int $b) {