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error[E0277]: `?` couldn't convert the error to `()`
--> $DIR/option-to-result.rs:5:6
|
LL | fn test_result() -> Result<(),()> {
| ------------- expected `()` because of this
LL | let a:Option<()> = Some(());
LL | a?;
| ^ the trait `std::convert::From<std::option::NoneError>` is not implemented for `()`
|
= note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait
= note: required by `std::convert::From::from`
help: consider converting the `Option<T>` into a `Result<T, _>` using `Option::ok_or` or `Option::ok_or_else`
|
LL | a.ok_or_else(|| /* error value */)?;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0277]: `?` couldn't convert the error to `std::option::NoneError`
--> $DIR/option-to-result.rs:11:6
|
LL | fn test_option() -> Option<i32>{
| ----------- expected `std::option::NoneError` because of this
LL | let a:Result<i32, i32> = Ok(5);
LL | a?;
| ^ the trait `std::convert::From<i32>` is not implemented for `std::option::NoneError`
|
= note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait
= note: required by `std::convert::From::from`
help: consider converting the `Result<T, _>` into an `Option<T>` using `Result::ok`
|
LL | a.ok()?;
| ^^^^^
error: aborting due to 2 previous errors
For more information about this error, try `rustc --explain E0277`.
|
