blob: ba85a7cada2329668ec3bebd3a3f3bb3a4fb05ba (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
|
error[E0277]: the `?` operator can only be used on `Result`s, not `Option`s, in a function that returns `Result`
--> $DIR/try-on-option.rs:5:6
|
LL | / fn foo() -> Result<u32, ()> {
LL | | let x: Option<u32> = None;
LL | | x?;
| | ^ use `.ok_or(...)?` to provide an error compatible with `Result<u32, ()>`
LL | | Ok(22)
LL | | }
| |_- this function returns a `Result`
|
= help: the trait `FromResidual<Option<Infallible>>` is not implemented for `Result<u32, ()>`
= 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 in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
--> $DIR/try-on-option.rs:11:6
|
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 `FromResidual<Option<Infallible>>` is not implemented for `u32`
error: aborting due to 2 previous errors
For more information about this error, try `rustc --explain E0277`.
|
