Performance optimizations on Fraction's constructor.
./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3)`
31.7 usec/loop -> 9.2 usec/loop
./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3, 2)'`
27.7 usec/loop -> 9.32 usec/loop
./python.exe -m timeit -s 'from fractions import Fraction; f = Fraction(3, 2)' 'Fraction(f)'
31.9 usec/loop -> 14.3 usec/loop
diff --git a/Lib/fractions.py b/Lib/fractions.py
index 53ff785..9dd49b1 100755
--- a/Lib/fractions.py
+++ b/Lib/fractions.py
@@ -64,7 +64,7 @@
"""
self = super(Fraction, cls).__new__(cls)
- if denominator == 1:
+ if type(numerator) not in (int, long) and denominator == 1:
if isinstance(numerator, basestring):
# Handle construction from strings.
input = numerator
@@ -86,24 +86,22 @@
if m.group('sign') == '-':
numerator = -numerator
- elif (not isinstance(numerator, numbers.Integral) and
- isinstance(numerator, Rational)):
- # Handle copies from other rationals.
+ elif isinstance(numerator, Rational):
+ # Handle copies from other rationals. Integrals get
+ # caught here too, but it doesn't matter because
+ # denominator is already 1.
other_rational = numerator
numerator = other_rational.numerator
denominator = other_rational.denominator
- if (not isinstance(numerator, numbers.Integral) or
- not isinstance(denominator, numbers.Integral)):
- raise TypeError("Fraction(%(numerator)s, %(denominator)s):"
- " Both arguments must be integral." % locals())
-
if denominator == 0:
raise ZeroDivisionError('Fraction(%s, 0)' % numerator)
+ numerator = numerator.__index__()
+ denominator = denominator.__index__()
g = gcd(numerator, denominator)
- self._numerator = int(numerator // g)
- self._denominator = int(denominator // g)
+ self._numerator = numerator // g
+ self._denominator = denominator // g
return self
@classmethod
diff --git a/Lib/test/test_fractions.py b/Lib/test/test_fractions.py
index 7929861..654456a 100644
--- a/Lib/test/test_fractions.py
+++ b/Lib/test/test_fractions.py
@@ -62,11 +62,11 @@
self.assertRaisesMessage(ZeroDivisionError, "Fraction(12, 0)",
F, 12, 0)
- self.assertRaises(TypeError, F, 1.5)
- self.assertRaises(TypeError, F, 1.5 + 3j)
+ self.assertRaises(AttributeError, F, 1.5)
+ self.assertRaises(AttributeError, F, 1.5 + 3j)
- self.assertRaises(TypeError, F, F(1, 2), 3)
- self.assertRaises(TypeError, F, "3/2", 3)
+ self.assertRaises(AttributeError, F, F(1, 2), 3)
+ self.assertRaises(AttributeError, F, "3/2", 3)
def testFromString(self):
self.assertEquals((5, 1), _components(F("5")))