Rick van Hattem
44 lines
1.1 KiB
ReStructuredText
44 lines
1.1 KiB
ReStructuredText
>>> class AddClassAttributeMeta(type):
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... def __init__(metaclass, name, bases, namespace, **kwargs):
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... # The kwargs should not be passed on to the
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... # type.__init__
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... type.__init__(metaclass, name, bases, namespace)
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...
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... def __new__(metaclass, name, bases, namespace, **kwargs):
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... for k, v in kwargs.items():
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... # setdefault so we don't overwrite attributes
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... namespace.setdefault(k, v)
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...
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... return type.__new__(metaclass, name, bases, namespace)
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>>> class WithArgument(metaclass=AddClassAttributeMeta, a=1234):
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... pass
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>>> WithArgument.a
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1234
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>>> with_argument = WithArgument()
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>>> with_argument.a
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1234
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------------------------------------------------------------------
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>>> class AddClassAttribute:
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... def __init_subclass__(cls, **kwargs):
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... super().__init_subclass__()
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...
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... for k, v in kwargs.items():
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... setattr(cls, k, v)
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>>> class WithAttribute(metaclass=AddClassAttributeMeta, a=1234):
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... pass
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>>> WithAttribute.a
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1234
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>>> with_attribute = WithAttribute()
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>>> with_attribute.a
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1234
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