debian-python-lml/lml/_compact.py

21 lines
982 B
Python

def with_metaclass(meta, *bases):
# This requires a bit of explanation: the basic idea is to make a
# dummy metaclass for one level of class instantiation that replaces
# itself with the actual metaclass. Because of internal type checks
# we also need to make sure that we downgrade the custom metaclass
# for one level to something closer to type (that's why __call__ and
# __init__ comes back from type etc.).
#
# This has the advantage over six.with_metaclass in that it does not
# introduce dummy classes into the final MRO.
# :copyright: (c) 2014 by Armin Ronacher.
# :license: BSD, see LICENSE for more details.
class metaclass(meta):
__call__ = type.__call__
__init__ = type.__init__
def __new__(cls, name, this_bases, d):
if this_bases is None:
return type.__new__(cls, name, (), d)
return meta(name, bases, d)
return metaclass('temporary_class', None, {})