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28 lines
1.3 KiB
Plaintext
28 lines
1.3 KiB
Plaintext
error[E0277]: the `?` operator can only be used on `Result`s, not `Option`s, in a function that returns `Result`
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--> $DIR/option-to-result.rs:5:6
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LL | fn test_result() -> Result<(),()> {
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| --------------------------------- this function returns a `Result`
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LL | let a:Option<()> = Some(());
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LL | a?;
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| ^ use `.ok_or(...)?` to provide an error compatible with `Result<(), ()>`
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= help: the trait `FromResidual<Option<Infallible>>` is not implemented for `Result<(), ()>`
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= help: the trait `FromResidual<Result<Infallible, E>>` is implemented for `Result<T, F>`
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error[E0277]: the `?` operator can only be used on `Option`s, not `Result`s, in a function that returns `Option`
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--> $DIR/option-to-result.rs:11:6
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LL | fn test_option() -> Option<i32>{
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| ------------------------------- this function returns an `Option`
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LL | let a:Result<i32, i32> = Ok(5);
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LL | a?;
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| ^ use `.ok()?` if you want to discard the `Result<Infallible, i32>` error information
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= help: the trait `FromResidual<Result<Infallible, i32>>` is not implemented for `Option<i32>`
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= help: the trait `FromResidual<Option<Infallible>>` is implemented for `Option<T>`
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error: aborting due to 2 previous errors
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For more information about this error, try `rustc --explain E0277`.
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