rust/compiler/rustc_parse/src/parser/expr.rs, branch 1.79.0

Revert "Rollup merge of #124099 - voidc:disallow-ambiguous-expr-attrs, r=davidtwco"

2024-06-07T01:12:48+00:00

This reverts commit 57dad1d75e562ff73051c1c43b07eaf65c7dbd74, reversing changes made to 36316df9fe6c3e246153fe6e78967643cf08c148.

Rollup merge of #124099 - voidc:disallow-ambiguous-expr-attrs, r=davidtwco

2024-04-23T10:10:26+00:00

Disallow ambiguous attributes on expressions This implements the suggestion in [#15701](https://github.com/rust-lang/rust/issues/15701#issuecomment-2033124217) to disallow ambiguous outer attributes on expressions. This should resolve one of the concerns blocking the stabilization of `stmt_expr_attributes`.

Improve handling of expr->field errors

2024-04-22T15:47:35+00:00

The current message for "`->` used for field access" is the following: ```rust error: expected one of `!`, `.`, `::`, `;`, `?`, `{`, `}`, or an operator, found `->` --> src/main.rs:2:6 | 2 | a->b; | ^^ expected one of 8 possible tokens ``` (playground link[1]) This PR tries to address this by adding a dedicated error message and recovery. The proposed error message is: ``` error: `->` used for field access or method call --> ./tiny_test.rs:2:6 | 2 | a->b; | ^^ help: try using `.` instead | = help: the `.` operator will dereference the value if needed ``` (feel free to bikeshed it as much as necessary) [1]: https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=7f8b6f4433aa7866124123575456f54e Signed-off-by: Sasha Pourcelot

Disallow ambiguous attributes on expressions

2024-04-18T18:42:19+00:00

remove some things that do not need to be

2024-04-11T19:09:52+00:00

Don't ICE for postfix match after as

2024-04-02T22:31:42+00:00

chore: fix some comments

2024-03-27T14:32:53+00:00

Signed-off-by: xiaoxiangxianzi

Clarify `parse_dot_suffix_expr`.

2024-03-25T02:08:07+00:00

For the `MiddleDot` case, current behaviour: - For a case like `1.2`, `sym1` is `1` and `sym2` is `2`, and `self.token` holds `1.2`. - It creates a new ident token from `sym1` that it puts into `self.token`. - Then it does `bump_with` with a new dot token, which moves the `sym1` token into `prev_token`. - Then it does `bump_with` with a new ident token from `sym2`, which moves the `dot` token into `prev_token` and discards the `sym1` token. - Then it does `bump`, which puts whatever is next into `self.token`, moves the `sym2` token into `prev_token`, and discards the `dot` token altogether. New behaviour: - Skips creating and inserting the `sym1` and dot tokens, because they are unnecessary. - This also demonstrates that the comment about `Spacing::Alone` is wrong -- that value is never used. That comment was added in #77250, and AFAICT it has always been incorrect. The commit also expands comments. I found this code hard to read previously, the examples in comments make it easier.

Change `parse_expr_tuple_field_access`.

2024-03-25T02:05:59+00:00

Pass in the span for the field rather than using `prev_token`. Also rename it `mk_expr_tuple_field_access`, because it doesn't do any actual parsing, it just creates an expression with what it's given. Not much of a clarity win by itself, but unlocks additional subsequent simplifications.

Remove `next_token` handling from `parse_expr_tuple_field_access`.

2024-03-25T02:05:59+00:00

It's clearer at the call site.