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error[E0277]: the `?` operator can only be used in an async block that returns `Result` or `Option` (or another type that implements `FromResidual`)
--> $DIR/try-on-option-in-async.rs:7:10
|
LL | async {
| ----- this function should return `Result` or `Option` to accept `?`
LL | let x: Option<u32> = None;
LL | x?;
| ^ cannot use the `?` operator in an async block that returns `{integer}`
|
= help: the trait `FromResidual<Option<Infallible>>` is not implemented for `{integer}`
error[E0277]: the `?` operator can only be used in an async closure that returns `Result` or `Option` (or another type that implements `FromResidual`)
--> $DIR/try-on-option-in-async.rs:16:10
|
LL | let async_closure = async || {
| __________________________________-
LL | | let x: Option<u32> = None;
LL | | x?;
| | ^ cannot use the `?` operator in an async closure that returns `u32`
LL | | 22_u32
LL | | };
| |_____- this function should return `Result` or `Option` to accept `?`
|
= help: the trait `FromResidual<Option<Infallible>>` is not implemented for `u32`
error[E0277]: the `?` operator can only be used in an async function that returns `Result` or `Option` (or another type that implements `FromResidual`)
--> $DIR/try-on-option-in-async.rs:25:6
|
LL | async fn an_async_function() -> u32 {
| _____________________________________-
LL | | let x: Option<u32> = None;
LL | | x?;
| | ^ cannot use the `?` operator in an async 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 3 previous errors
For more information about this error, try `rustc --explain E0277`.
|
