[issue36541] Make lib2to3 grammar more closely match Python

Change by Gregory P. Smith : -- assignee: -> gregory.p.smith nosy: +gregory.p.smith ___ Python tracker ___ ___ Python-bugs-list

[issue36541] Make lib2to3 grammar more closely match Python

Change by Gregory P. Smith : -- versions: +Python 3.9 -Python 3.6 ___ Python tracker ___ ___ Python-bugs-list mailing list

[issue36541] Make lib2to3 grammar more closely match Python

Peter Ludemann added the comment: Also the Grammar.txt diffs look about the same size as I've seen with other upgrades to lib2to3 when the Python grammar changed. -- ___ Python tracker

[issue36541] Make lib2to3 grammar more closely match Python

Peter Ludemann added the comment: Re: breakage due to changes in structure (https://bugs.python.org/issue36541#msg339669) ... this has already happened in the past (e.g., type annotations and async). It's probably a good idea to add some documentation that structure changes can be

[issue36541] Make lib2to3 grammar more closely match Python

Tim Hatch added the comment: My strong preference would be getting the lib2to3 grammar to be the python grammar + additions, to make future changes easier to merge. The strongest argument against doing that is the backwards-incompatibility of patterns -- some won't compile, while others

[issue36541] Make lib2to3 grammar more closely match Python

Pablo Galindo Salgado added the comment: For the changes of PEP570, please wait until I merge the implementation to do the grammar changes in lib2to3 for that. -- ___ Python tracker

[issue36541] Make lib2to3 grammar more closely match Python

Lisa Roach added the comment: I agree we should get lib2to3 up to date. Looks like for *args and **kwargs there is issue33348 (this has a PR) and issue32496 (no PR) and related closed issue24791 and issue24176. Adding `:=` seems straighforward to me, as for the big change maybe

[issue36541] Make lib2to3 grammar more closely match Python

Change by Karthikeyan Singaravelan : -- nosy: +benjamin.peterson ___ Python tracker ___ ___ Python-bugs-list mailing list

[issue36541] Make lib2to3 grammar more closely match Python

Tim Hatch added the comment: Here's approximately what it would look like to do the big change now: https://github.com/python/cpython/compare/master...thatch:lib2to3-update-grammar (one test failing, and some helpers may need more test coverage) --

[issue36541] Make lib2to3 grammar more closely match Python

Tim Hatch added the comment: jreese reminded me of pep570, which will make more grammar changes. I'm open to the idea of replacing the grammar with the live one, plus porting the 2isms forward like print, eval, except with comma. My sincere hope is that everyone that depends on this

[issue36541] Make lib2to3 grammar more closely match Python

Change by Pablo Galindo Salgado : -- nosy: +pablogsal ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue36541] Make lib2to3 grammar more closely match Python

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[issue36541] Make lib2to3 grammar more closely match Python

Change by Roundup Robot : -- keywords: +patch pull_requests: +12626 stage: -> patch review ___ Python tracker ___ ___

[issue36541] Make lib2to3 grammar more closely match Python

New submission from Tim Hatch : The grammar in lib2to3 is out of date and can't parse `:=` nor `f(**not x)` from running on real code. I've done a cursory `diff -uw Grammar/Grammar Lib/lib2to3/grammar.txt`, and would like to fix lib2to3 so we can merge into both fissix and blib2to3, to