cardinal_pythonlib.metaclasses


Original code copyright (C) 2009-2022 Rudolf Cardinal (rudolf@pobox.com).

This file is part of cardinal_pythonlib.

Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at

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Support functions to do with metaclasses. IGNORE; NOT WORKING PROPERLY.

class cardinal_pythonlib.metaclasses.CooperativeMeta(name: str, bases: Tuple[Type[CT_co], ...], members: Dict[str, Any])[source]

The idea is to use this as the metaclass for a class Derived that inherits from bases BaseOne, BaseTwo, …, whose metaclasses are not of the same type.

This should avoid the error:

TypeError: metaclass conflict: the metaclass of a derived class must
be a (non-strict) subclass of the metaclasses of all its bases

Code from: https://stackoverflow.com/questions/6557407/triple-inheritance-causes-metaclass-conflict-sometimes.

See also: https://code.activestate.com/recipes/204197-solving-the-metaclass-conflict/.

HOWEVER, it’s not actually working. Does Python 3 have stricter checking than Python 2?

See also https://blog.ionelmc.ro/2015/02/09/understanding-python-metaclasses/.

class cardinal_pythonlib.metaclasses.DebuggingCooperativeMeta(name: str, bases: Tuple[Type[CT_co], ...], members: Dict[str, Any])[source]

CooperativeMeta, but with print() output. Still not working.