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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:7:6
|
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`
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= help: the trait `FromResidual<Option<Infallible>>` is not implemented for `Result<u32, ()>`
note: required by `from_residual`
--> $SRC_DIR/core/src/ops/try_trait.rs:LL:COL
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LL | fn from_residual(residual: R) -> Self;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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:13:6
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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`
note: required by `from_residual`
--> $SRC_DIR/core/src/ops/try_trait.rs:LL:COL
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LL | fn from_residual(residual: R) -> Self;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: aborting due to 2 previous errors
For more information about this error, try `rustc --explain E0277`.
|
