| #!/usr/bin/env python3 | |
| # Copyright 2025 Google LLC | |
| # 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 | |
| # | |
| # http://www.apache.org/licenses/LICENSE-2.0 | |
| # | |
| # Unless required by applicable law or agreed to in writing, software | |
| # distributed under the License is distributed on an "AS IS" BASIS, | |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
| # See the License for the specific language governing permissions and | |
| # limitations under the License. | |
| import functools | |
| from typing import List | |
| class StringList(list): | |
| """ | |
| A hashable ordered list of strings. | |
| This can be used as the key for a dictionary. | |
| """ | |
| def __init__(self, strs: List[str]) -> None: | |
| super().__init__(strs) | |
| def __hash__(self) -> int: # type: ignore[override] | |
| return functools.reduce(lambda h, ir: hash((h, hash(ir))), self, 0) |