René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"PEP 649: `functools.update_wrapper` implementation","articleBody":"The current implementation of PEP-649 and PEP-749 on main simply copies functions' `__annotate__` in `functools.update_wrapper` (and thence `functools.wraps`):\r\n\r\n```\r\n\u003e\u003e\u003e def f(x: y): pass\r\n... \r\n\u003e\u003e\u003e from functools import wraps\r\n\u003e\u003e\u003e @wraps(f)\r\n... def g(x): pass\r\n... \r\n\u003e\u003e\u003e g.__annotate__ is f.__annotate__\r\nTrue\r\n```\r\n\r\nBut as @ncoghlan pointed out (https://github.com/larryhastings/co_annotations/issues/21,  https://discuss.python.org/t/pep-749-implementing-pep-649/54974/4), this may not be what we want in the case where the original function's `__annotations__` have been modified:\r\n\r\n```\r\n\u003e\u003e\u003e def f(x: int): pass\r\n... \r\n\u003e\u003e\u003e f.__annotations__[\"x\"] = 42\r\n\u003e\u003e\u003e @wraps(f)\r\n... def g(x): pass\r\n... \r\n\u003e\u003e\u003e f.__annotations__\r\n{'x': 42}\r\n\u003e\u003e\u003e g.__annotations__\r\n{'x': \u003cclass 'int'\u003e}\r\n```\r\n\r\nAlyssa therefore suggests making `update_wrapper` create a wrapper `__annotate__` function that looks in the original function's `__annotations__` first. This doesn't fit neatly into `update_wrapper`'s current structure of WRAPPER_ASSIGNMENTS and WRAPPER_UPDATES, so we should add a third bucket, maybe WRAPPER_DELEGATIONS.\n\n\u003c!-- gh-linked-prs --\u003e\n### Linked PRs\n* gh-124346\n\u003c!-- /gh-linked-prs --\u003e\n","author":{"url":"https://github.com/JelleZijlstra","@type":"Person","name":"JelleZijlstra"},"datePublished":"2024-09-23T14:49:20.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":5},"url":"https://github.com/124342/cpython/issues/124342"}