| # Copyright 2009-2024 Joshua Bronson. All rights reserved. | |
| # | |
| # This Source Code Form is subject to the terms of the Mozilla Public | |
| # License, v. 2.0. If a copy of the MPL was not distributed with this | |
| # file, You can obtain one at http://mozilla.org/MPL/2.0/. | |
| # * Code review nav * | |
| # (see comments in __init__.py) | |
| # ============================================================================ | |
| # ← Prev: _base.py Current: _frozen.py Next: _bidict.py → | |
| # ============================================================================ | |
| """Provide :class:`frozenbidict`, an immutable, hashable bidirectional mapping type.""" | |
| from __future__ import annotations | |
| import typing as t | |
| from ._base import BidictBase | |
| from ._typing import KT | |
| from ._typing import VT | |
| class frozenbidict(BidictBase[KT, VT]): | |
| """Immutable, hashable bidict type.""" | |
| _hash: int | |
| if t.TYPE_CHECKING: | |
| def inverse(self) -> frozenbidict[VT, KT]: ... | |
| def inv(self) -> frozenbidict[VT, KT]: ... | |
| def __hash__(self) -> int: | |
| """The hash of this bidict as determined by its items.""" | |
| if getattr(self, '_hash', None) is None: | |
| # The following is like hash(frozenset(self.items())) | |
| # but more memory efficient. See also: https://bugs.python.org/issue46684 | |
| self._hash = t.ItemsView(self)._hash() | |
| return self._hash | |
| # * Code review nav * | |
| # ============================================================================ | |
| # ← Prev: _base.py Current: _frozen.py Next: _bidict.py → | |
| # ============================================================================ | |