35 lines
839 B
Python
35 lines
839 B
Python
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from collections.abc import Mapping
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class FrozenDict(Mapping):
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dict_cls = dict
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def __init__(self, *args, **kwargs):
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self._dict = self.dict_cls(*args, **kwargs)
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self._hash = None
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def __getitem__(self, key):
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return self._dict[key]
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def __contains__(self, key):
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return key in self._dict
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def copy(self, **add_or_replace):
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return self.__class__(self, **add_or_replace)
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def __iter__(self):
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return iter(self._dict)
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def __len__(self):
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return len(self._dict)
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def __repr__(self):
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return f"<{self.__class__.__name__} {repr(self._dict)}>"
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def __hash__(self):
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if self._hash is None:
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self._hash = 0
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for key, value in self._dict.items():
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self._hash ^= hash((key, value))
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return self._hash
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