René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"ForwardRef: remove `__hash__` and `__eq__`","articleBody":"# Feature or enhancement\n\nCurrently, `annotationlib.ForwardRef` has a `__hash__` and `__eq__` method, which look at a few attributes: https://github.com/python/cpython/blob/8b4a0d641cde667f94ce49f5e64da6bd9d6fbd9c/Lib/typing.py#L1096 (3.13). These look unsound already; it's possible for two ForwardRefs to compare equal but hash differently (if they have the same evaluated value but not the same `__forward_module__`). This gets worse on 3.14, where ForwardRef has gained a few more fields (https://github.com/python/cpython/blob/a4722449caccc42ad644611d02fbdb5005f601eb/Lib/annotationlib.py#L232).\n\nI think it's better to remove the `__eq__` and `__hash__` methods from `ForwardRef` objects, and make it so two ForwardRefs are equal only if they're identical. I don't see a good use case for comparing two ForwardRefs for equality; if you want to know that they refer to the same thing, you should evaluate them and compare the type object that comes out.\n\nThis came up in agronholm/typeguard#492 where the current implementation of equality caused some grief. cc people involved with some runtime type checking tools: @agronholm @Viicos @leycec.\n\n\u003c!-- gh-linked-prs --\u003e\n### Linked PRs\n* gh-129465\n* gh-132283\n\u003c!-- /gh-linked-prs --\u003e\n","author":{"url":"https://github.com/JelleZijlstra","@type":"Person","name":"JelleZijlstra"},"datePublished":"2025-01-30T04:50:05.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":6},"url":"https://github.com/129463/cpython/issues/129463"}