Add a note to patterns.ident.precedent #2022
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This attempts to clarify the parsing ambiguity between `IdentifierPattern` and `PathPattern`. See [`PatKind::Ident`] and [`lower_pat_ident`]. Closes rust-lang#605 [`PatKind::Ident`]: https://github.com/rust-lang/rust/blob/dc2c3564d273cf8ccce32dc4f47eaa27063bceb9/compiler/rustc_ast/src/ast.rs#L862-L866 [`lower_pat_ident`]: https://github.com/rust-lang/rust/blob/dc2c3564d273cf8ccce32dc4f47eaa27063bceb9/compiler/rustc_ast_lowering/src/pat.rs#L278-L333
Let's extend the example to demonstrate, comparatively, what is parsed as an `IdentifierPattern`. Even though this is the common case, showing this might be helpful to people less familiar with the grammar. Let's remove `main`, as that's not needed here. And, in the code, let's highlight specifically what we're commenting on by commenting below the construct.
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This PR was rebased onto a different master commit. Here's a range-diff highlighting what actually changed. Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers. |
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This attempts to clarify the parsing ambiguity between IdentifierPattern and PathPattern.
See
PatKind::Identandlower_pat_ident.Closes #605