gh-127833: Reword and expand the Notation section #134443
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Prepare the docs for using the notation used in the `python.gram` file. If we want to sync the two, the meta-syntax should be the same. Also, remove the distinction between lexical and syntactic rules. With f- and t-strings, the line between the two is blurry.
Co-authored-by: Blaise Pabon <[email protected]>
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@lysnikolaou, does this look correct to you? |
Co-authored-by: Blaise Pabon <[email protected]> Co-authored-by: Adam Turner <[email protected]>
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I'll have a look at this tomorrow if that's okay. |
Doc/reference/introduction.rst
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| * ``"a"..."z"``: Two literal characters separated by three dots mean a choice | ||
| of any single character in the given (inclusive) range of ASCII characters. | ||
| * ``<...>``: A phrase between angular brackets gives an informal description | ||
| of the matched symbol (for example, ``<any ASCII character except "\">``), | ||
| or an abbreviation that is defined in nearby text (for example, ``<Lu>``). |
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Should we be mentioning somewhere that these are not part of the actual Python grammar, but part of the notation to make it easier to describe specific constructs? Maybe as part of the first paragraph that says that this is a mixture of EBNF and PEG?
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I moved them to the end, and (re-)added notes that they're only used in the lexer definitions.
| The definition to the right of the colon uses the following syntax elements: | ||
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| * ``name``: A name refers to another rule. | ||
| Where possible, it is a link to the rule's definition. |
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What possibilities exist, other than referencing another rule?
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Rules that aren't defined by formal grammar in the docs, for example strings in https://docs.python.org/3/reference/compound_stmts.html#literal-patterns
I consider these to be issues that #127833 should eventually fix, but until then I'd keep the weasel word in.
Also: tokens are currently unlinked, and many don't have a (lexical) grammar rule so they should eventually link to prose.
Co-authored-by: Lysandros Nikolaou <[email protected]> Co-authored-by: Colin Marquardt <[email protected]>
Prepare the docs for using the notation used in the
python.gramfile. If we want to sync the two, the meta-syntax should be the same.Also, remove the distinction between lexical and syntactic rules.
With f- and t-strings, the line between the two is blurry.
📚 Documentation preview 📚: https://cpython-previews--134443.org.readthedocs.build/