Better diagnostics for '..' pattern fragment not in the last position #49268
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| let p = Point { x: 0, y: 0 }; | ||
| let Point { .., y } = p; //~ ERROR expected `}`, found `,` | ||
| //~| ERROR pattern does not mention field `x` | ||
| //~| ERROR pattern does not mention field `y` |
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Note that the pattern mentions field y actually.
Ideally we should do recovery in the parser and continue parsing fields after encountering incorrect .., but it requires somewhat larger refactoring of fn parse_pat_fields.
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@petrochenkov Would it be possible to just hide the "pattern does not metion field" errors?
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@Badel2
Yes, but in this case Pat { .., field } or Pat { field, .., } have a single obvious meaning, so it's better to use recovery at syntax level and starting from that assume that Pat { field, .. } was actually implied.
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…trochenkov Better diagnostics for '..' pattern fragment not in the last position Fixes rust-lang#49257.
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…trochenkov Better diagnostics for '..' pattern fragment not in the last position Fixes rust-lang#49257.
…trochenkov Better diagnostics for '..' pattern fragment not in the last position Fixes rust-lang#49257.
Accept `..` in incorrect position to avoid further errors We currently give a specific message when encountering a `..` anywhere other than the end of a pattern. Modify the parser to accept it (while still emitting the error) so that we don't also trigger "missing fields in pattern" errors afterwards. Add suggestions to either remove trailing `,` or moving the `..` to the end. Follow up to rust-lang#49268.
Accept `..` in incorrect position to avoid further errors We currently give a specific message when encountering a `..` anywhere other than the end of a pattern. Modify the parser to accept it (while still emitting the error) so that we don't also trigger "missing fields in pattern" errors afterwards. Add suggestions to either remove trailing `,` or moving the `..` to the end. Follow up to #49268.
Fixes #49257.