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error[E0277]: the `?` operator can only be used on `Result`s, not `Option`s, in a function that returns `Result`
--> $DIR/option-to-result.rs:5:6
|
LL | fn test_result() -> Result<(),()> {
| --------------------------------- this function returns a `Result`
LL | let a:Option<()> = Some(());
LL | a?;
| ^ use `.ok_or(...)?` to provide an error compatible with `Result<(), ()>`
|
= help: the trait `FromResidual<Option<Infallible>>` is not implemented for `Result<(), ()>`
= help: the following other types implement trait `FromResidual<R>`:
<Result<T, F> as FromResidual<Result<Infallible, E>>>
<Result<T, F> as FromResidual<Yeet<E>>>
error[E0277]: the `?` operator can only be used on `Option`s, not `Result`s, in a function that returns `Option`
--> $DIR/option-to-result.rs:11:6
|
LL | fn test_option() -> Option<i32>{
| ------------------------------- this function returns an `Option`
LL | let a:Result<i32, i32> = Ok(5);
LL | a?;
| ^ use `.ok()?` if you want to discard the `Result<Infallible, i32>` error information
|
= help: the trait `FromResidual<Result<Infallible, i32>>` is not implemented for `Option<i32>`
= help: the following other types implement trait `FromResidual<R>`:
<Option<T> as FromResidual<Yeet<()>>>
<Option<T> as FromResidual>
error: aborting due to 2 previous errors
For more information about this error, try `rustc --explain E0277`.
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