Guido van Rossum added the comment: PS. I can shave off nearly 4 usec of the constructor like this:
- self = super(Fraction, cls).__new__(cls) + if cls is Fraction: + self = object.__new__(cls) + else: + self = super().__new__(cls) This would seem to give an upper bound for the gain you can make by moving the check for instantiating an abstract class to C. Your call. I also found that F(2,3)+F(5,7) takes about 22 usecs (or 18 using the above hack). Inlining the common case for addition (Fraction+Fraction) made that go down to 14 usec (combined with the above hack): - __add__, __radd__ = _operator_fallbacks(_add, operator.add) + __xadd__, __radd__ = _operator_fallbacks(_add, operator.add) + def __add__(self, other): + if type(other) is Fraction: + na = self._numerator + da = self._denominator + nb = other._numerator + db = other._denominator + return Fraction(na*db + nb*da, da*db) + return self.__xadd__(other) + __________________________________ Tracker <[EMAIL PROTECTED]> <http://bugs.python.org/issue1682> __________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
