svn+ssh://pythondev@svn.python.org/python/trunk
........
r77788 | benjamin.peterson | 2010-01-26 20:15:28 -0600 (Tue, 26 Jan 2010) | 1 line
for UserDict to be compatible with abcs, it must subclass object
........
r77789 | benjamin.peterson | 2010-01-26 20:16:42 -0600 (Tue, 26 Jan 2010) | 1 line
raise a clear TypeError when trying to register a non-class
........
which forbids constructing types that have it set. The effect is to speed
./python.exe -m timeit -s 'import abc' -s 'class Foo(object): __metaclass__ = abc.ABCMeta' 'Foo()'
up from 2.5us to 0.201us. This fixes issue 1762.
./python.exe -m timeit -s 'from fractions import Fraction; f = Fraction(3, 2)' 'isinstance(3, Fraction); isinstance(f, Fraction)'
from 12.3 usec/loop to 3.44 usec/loop and
./python.exe -m timeit -s 'from fractions import Fraction' 'Fraction(3, 2)'
from 48.8 usec to 23.6 usec by avoiding genexps and sets in __instancecheck__
and inlining the common case from __subclasscheck__.
Backport abc.py and isinstance/issubclass overloading to 2.6.
I had to backport test_typechecks.py myself, and make one small change
to abc.py to avoid duplicate work when x.__class__ and type(x) are the
same.