Hello, I am trying to implement PEP-637, and I started modifying the parser and the grammar, but I don't know what I am missing.
The PR is here https://github.com/python/cpython/compare/master...stefanoborini:PEP-637-implementation-attempt-1?expand=1 It includes other stuff but the core is that I extended the Subscript in the asdl to accept the keyword args | Subscript(expr value, expr slice, keyword* keywords, expr_context ctx) which seems to work: >>> ast.parse('a[3]').body[0].value.keywords [] I also added a few "productions" (I believe they are called like this, my compiler theory is very approximated), one of which is now primary[expr_ty]: .... | a=primary '[' b=slices c=[',' k=kwargs {k}]']' { _Py_Subscript(a, b, c, Load, EXTRA) } I also tried with additional formats like | a=primary '[' b=slices c=kwargs ']' { _Py_Subscript(a, b, c, Load, EXTRA) } or even just | a=primary '[' c=kwargs ']' { _Py_Subscript(a, NULL, c, Load, EXTRA) } but I always get a SyntaxError: >>> ast.parse('a[k=3]').body[0].value.keywords Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/Users/sbo/Work/Projects/stefanoborini/cpython/Lib/ast.py", line 50, in parse return compile(source, filename, mode, flags, File "<unknown>", line 1 a[k=3] ^ SyntaxError: invalid syntax Note that I always recreated ast parser and pegen.c with 'make regen-all' and recompiled with make. I tried to enable debug and print the pegen.c debug, but it's a bit heavy and I could not immediately spot the issue. I suspect I am missing something somewhere. Thanks -- Kind regards, Stefano Borini _______________________________________________ Python-Dev mailing list -- python-dev@python.org To unsubscribe send an email to python-dev-le...@python.org https://mail.python.org/mailman3/lists/python-dev.python.org/ Message archived at https://mail.python.org/archives/list/python-dev@python.org/message/RZYDHYZPTPGLBX4VCR6HTYGJ3GL2CWIX/ Code of Conduct: http://python.org/psf/codeofconduct/
