René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Nested attribute lookup for improved error messages executes property code","articleBody":"# Bug report\n\n### Bug description:\n\nThe new error messages for nested attributes will execute descriptors/property code\n\nModified example from the change log. Gave the property a side effect (print)\n```python\nfrom dataclasses import dataclass\nfrom math import pi\n\n@dataclass\nclass Circle:\n   radius: float\n   @property\n   def area(self) -\u003e float:\n      print(\"Property 'area' accessed\")\n      return pi * self.radius**2\n\nclass Container:\n   def __init__(self, inner: Circle) -\u003e None:\n      self.inner = inner\n\ncircle = Circle(radius=4.0)\ncontainer = Container(circle)\nprint(container.area)\n```\n\nOutput\n```\nProperty 'area' accessed\nTraceback (most recent call last):\n  File \"\u003cstdin\u003e\", line 1, in \u003cmodule\u003e\n    print(container.area)\n          ^^^^^^^^^^^^^^\nAttributeError: 'Container' object has no attribute 'area'. Did you mean '.inner.area' instead of '.area'?\n```\n\nExpected would be to not execute the code. This does not happen when the `Container` class has a property suggested\n\nPR incoming\n\n### CPython versions tested on:\n\nCPython main branch\n\n### Operating systems tested on:\n\nWindows\n\n\u003c!-- gh-linked-prs --\u003e\n### Linked PRs\n* gh-145414\n\u003c!-- /gh-linked-prs --\u003e\n","author":{"url":"https://github.com/Hiumee","@type":"Person","name":"Hiumee"},"datePublished":"2026-03-02T11:33:48.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/145413/cpython/issues/145413"}