Improve handling of expr->field errors

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 <sasha.pourcelot@protonmail.com>

0 files changed, 0 insertions, 0 deletions