Restore compatibility with Python 3.9's legacy LL(1) parser #4423
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The legacy LL(1) parser cannot handle compound with-statements using grouping parentheses and the `EXPR as TARGET` syntax, because it is not LL(1)-recognizable. This partially reverts commit f151eec.
Zac-HD
approved these changes
May 31, 2025
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Thanks as well! |
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The legacy LL(1) parser cannot handle compound with-statements using grouping parentheses and the
EXPR as TARGETsyntax, because it is not LL(1)-recognizable.This partially reverts commit f151eec.
Fixes #4421.
With this, to the best of my knowledge1, there are no current LL(1) parser failures in the
srcdirectory of the current (6.131.32) codebase.There are still some such non-parsable expressions left over in the tests. Should I bother with those? There should be no differences compared to running Python 3.9 with the newer PEG-based parser, save for lack of parsing errors.
Footnotes
grep -E '^ *with\b'↩