Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Invalid ? suggestion on mismatched Ok(T) #116967

Closed
eopb opened this issue Oct 20, 2023 · 1 comment · Fixed by #116968
Closed

Invalid ? suggestion on mismatched Ok(T) #116967

eopb opened this issue Oct 20, 2023 · 1 comment · Fixed by #116968
Assignees
Labels
A-diagnostics Area: Messages for errors, warnings, and lints T-compiler Relevant to the compiler team, which will review and decide on the PR/issue.

Comments

@eopb
Copy link
Contributor

eopb commented Oct 20, 2023

Code

pub fn foo() -> Result<String, ()> {
    let out: Result<(), ()> = Ok(());
    out
}

Current output

Compiling playground v0.0.1 (/playground)
error[E0308]: mismatched types
 --> src/lib.rs:3:5
  |
1 | pub fn foo() -> Result<String, ()> {
  |                 ------------------ expected `Result<String, ()>` because of return type
2 |     let out: Result<(), ()> = Ok(());
3 |     out
  |     ^^^ expected `Result<String, ()>`, found `Result<(), ()>`
  |
  = note: expected enum `Result<String, _>`
             found enum `Result<(), _>`
help: use `?` to coerce and return an appropriate `Err`, and wrap the resulting value in `Ok` so the expression remains of type `Result`
  |
3 |     Ok(out?)
  |     +++   ++

For more information about this error, try `rustc --explain E0308`.
error: could not compile `playground` (lib) due to previous error

Desired output

Compiling playground v0.0.1 (/playground)
error[E0308]: mismatched types
 --> src/lib.rs:3:5
  |
1 | pub fn foo() -> Result<String, ()> {
  |                 ------------------ expected `Result<String, ()>` because of return type
2 |     let out: Result<(), ()> = Ok(());
3 |     out
  |     ^^^ expected `Result<String, ()>`, found `Result<(), ()>`
  |
  = note: expected enum `Result<String, _>`
             found enum `Result<(), _>`
For more information about this error, try `rustc --explain E0308`.
error: could not compile `playground` (lib) due to previous error

Rationale and extra context

The suggestion is invalid

Other cases

No response

Anything else?

No response

@eopb eopb added A-diagnostics Area: Messages for errors, warnings, and lints T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Oct 20, 2023
@rustbot rustbot added the needs-triage This issue may need triage. Remove it if it has been sufficiently triaged. label Oct 20, 2023
@eopb
Copy link
Contributor Author

eopb commented Oct 20, 2023

@rustbot claim

@bors bors closed this as completed in 934cbe4 Oct 27, 2023
rust-timer added a commit to rust-lang-ci/rust that referenced this issue Oct 27, 2023
Rollup merge of rust-lang#116968 - eopb:116967, r=petrochenkov

Invalid `?` suggestion on mismatched `Ok(T)`

fixes: rust-lang#116967
@fmease fmease removed the needs-triage This issue may need triage. Remove it if it has been sufficiently triaged. label Oct 28, 2023
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
A-diagnostics Area: Messages for errors, warnings, and lints T-compiler Relevant to the compiler team, which will review and decide on the PR/issue.
Projects
None yet
Development

Successfully merging a pull request may close this issue.

3 participants