[issue37646] eval() in a list comprehension

Raymond Hettinger added the comment: New changeset 9341dcb4b9520ab92df10d4256e93a50e1e7d19f by Raymond Hettinger (Miss Islington (bot)) in branch '3.8': bpo-37646: Document that eval() cannot access nested scopes (GH-15117) (GH-15155) https://github.com/python/cpython/commit/9341dcb4b9520ab

[issue37646] eval() in a list comprehension

Change by Raymond Hettinger : -- assignee: -> docs@python components: +Documentation -Interpreter Core nosy: +docs@python resolution: -> fixed stage: patch review -> resolved status: open -> closed ___ Python tracker

[issue37646] eval() in a list comprehension

Change by miss-islington : -- pull_requests: +14888 pull_request: https://github.com/python/cpython/pull/15155 ___ Python tracker ___ __

[issue37646] eval() in a list comprehension

Raymond Hettinger added the comment: New changeset 610a4823cc0a3c2380ad0dfe64ae483ced4e5304 by Raymond Hettinger in branch 'master': bpo-37646: Document that eval() cannot access nested scopes (GH-15117) https://github.com/python/cpython/commit/610a4823cc0a3c2380ad0dfe64ae483ced4e5304

[issue37646] eval() in a list comprehension

Raymond Hettinger added the comment: After more thought, I think the existing behavior is probably what we want. There may not be a clean way to allow access and updates to non-locals. Even if a way was found, it may tie our hands and preclude other implementation changes down the road. A

[issue37646] eval() in a list comprehension

Change by Raymond Hettinger : -- keywords: +patch pull_requests: +14858 stage: resolved -> patch review pull_request: https://github.com/python/cpython/pull/15117 ___ Python tracker __

[issue37646] eval() in a list comprehension

Grzegorz Krasoń added the comment: I re-opened the issue. Dear core developers, can we ask you to confirm if described behavior of eval() is expected? -- ___ Python tracker _

[issue37646] eval() in a list comprehension

Change by Grzegorz Krasoń : -- resolution: not a bug -> status: closed -> open ___ Python tracker ___ ___ Python-bugs-list mailing l

[issue37646] eval() in a list comprehension

Steven D'Aprano added the comment: I'm not sure we should be so quick to close this. At the very least, I think the documentation could be improved. It does seem desirable to have the invariant: `expression` == `eval("expression")` apply in any environment. Was the change in behaviour b

[issue37646] eval() in a list comprehension

Grzegorz Krasoń added the comment: Steven, I believed that any `` replaced by `eval('')` will not change behaviour of the code. Now I understand that my assumption was incorrect. Raymond, thanks for helping me understand this. -- resolution: -> not a bug stage: -> resolved status:

[issue37646] eval() in a list comprehension

Raymond Hettinger added the comment: This used to work as you expected in Python 2. In Python 3, list comprehensions create their own inner scope just like generator expressions. Per the eval() docs, "if both dictionaries are omitted, the expression is executed in the environment where ev

[issue37646] eval() in a list comprehension

Steven D'Aprano added the comment: What leads you to believe that eval *shouldn't* work in the global scope in a comprehension? If not the global scope, which scope should it be, local or nonlocal? Is the behaviour documented differently? For reference, the current docs for eval are here: h

[issue37646] eval() in a list comprehension

New submission from Grzegorz Krasoń : eval() works in a global scope when invoked in a list comprehension. -- components: Interpreter Core files: demo.py messages: 348271 nosy: Grzegorz Krasoń priority: normal severity: normal status: open title: eval() in a list comprehension type: beha