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error[E0277]: `?` couldn't convert the error to `()`
--> $DIR/try-on-option.rs:7:6
|
LL | fn foo() -> Result<u32, ()> {
| --------------- expected `()` because of this
LL | let x: Option<u32> = None;
LL | x?;
| ^ the trait `From<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 `from`
help: consider converting the `Option<T>` into a `Result<T, _>` using `Option::ok_or` or `Option::ok_or_else`
|
LL | x.ok_or_else(|| /* error value */)?;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
--> $DIR/try-on-option.rs:13:5
|
LL | / fn bar() -> u32 {
LL | | let x: Option<u32> = None;
LL | | x?;
| | ^^ cannot use the `?` operator in a function that returns `u32`
LL | | 22
LL | | }
| |_- this function should return `Result` or `Option` to accept `?`
|
= help: the trait `Try` is not implemented for `u32`
= note: required by `from_error`
error: aborting due to 2 previous errors
For more information about this error, try `rustc --explain E0277`.
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