33 lines
850 B
Python
33 lines
850 B
Python
from typing import Any, TypeVar
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class _DefaultPlaceholder:
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"""
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You shouldn't use this class directly.
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It's used internally to recognize when a default value has been overwritten, even
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if the overridden default value was truthy.
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"""
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def __init__(self, value: Any):
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self.value = value
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def __bool__(self) -> bool:
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return bool(self.value)
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def __eq__(self, o: object) -> bool:
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return isinstance(o, _DefaultPlaceholder) and o.value == self.value
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_TDefaultType = TypeVar("_TDefaultType")
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def Default(value: _TDefaultType) -> _TDefaultType:
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"""
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You shouldn't use this function directly.
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It's used internally to recognize when a default value has been overwritten, even
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if the overridden default value was truthy.
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"""
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return _DefaultPlaceholder(value) # type: ignore
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