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45 lines
1.9 KiB
Plaintext
45 lines
1.9 KiB
Plaintext
error[E0277]: the `?` operator can only be used in an async block that returns `Result` or `Option` (or another type that implements `FromResidual`)
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--> $DIR/try-on-option-in-async.rs:8:10
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LL | / async {
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LL | | let x: Option<u32> = None;
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LL | | x?;
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| | ^ cannot use the `?` operator in an async block that returns `{integer}`
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LL | | 22
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LL | | }
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| |_____- this function should return `Result` or `Option` to accept `?`
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= help: the trait `FromResidual<Option<Infallible>>` is not implemented for `{integer}`
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error[E0277]: the `?` operator can only be used in an async closure that returns `Result` or `Option` (or another type that implements `FromResidual`)
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--> $DIR/try-on-option-in-async.rs:17:10
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LL | let async_closure = async || {
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| __________________________________-
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LL | | let x: Option<u32> = None;
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LL | | x?;
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| | ^ cannot use the `?` operator in an async closure that returns `u32`
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LL | | 22_u32
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LL | | };
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| |_____- this function should return `Result` or `Option` to accept `?`
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= help: the trait `FromResidual<Option<Infallible>>` is not implemented for `u32`
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error[E0277]: the `?` operator can only be used in an async function that returns `Result` or `Option` (or another type that implements `FromResidual`)
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--> $DIR/try-on-option-in-async.rs:26:6
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LL | async fn an_async_function() -> u32 {
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| _____________________________________-
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LL | | let x: Option<u32> = None;
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LL | | x?;
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| | ^ cannot use the `?` operator in an async function that returns `u32`
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LL | | 22
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LL | | }
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| |_- this function should return `Result` or `Option` to accept `?`
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= help: the trait `FromResidual<Option<Infallible>>` is not implemented for `u32`
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error: aborting due to 3 previous errors
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For more information about this error, try `rustc --explain E0277`.
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