43 lines
1.7 KiB
Plaintext
43 lines
1.7 KiB
Plaintext
error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `std::ops::Try`)
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--> $DIR/try-operator-on-main.rs:9:5
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LL | std::fs::File::open("foo")?; //~ ERROR the `?` operator can only
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| ^^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
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= help: the trait `std::ops::Try` is not implemented for `()`
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= note: required by `std::ops::Try::from_error`
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error[E0277]: the `?` operator can only be applied to values that implement `std::ops::Try`
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--> $DIR/try-operator-on-main.rs:12:5
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LL | ()?; //~ ERROR the `?` operator can only
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| ^^^ the `?` operator cannot be applied to type `()`
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= help: the trait `std::ops::Try` is not implemented for `()`
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= note: required by `std::ops::Try::into_result`
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error[E0277]: the trait bound `(): std::ops::Try` is not satisfied
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--> $DIR/try-operator-on-main.rs:15:5
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LL | try_trait_generic::<()>(); //~ ERROR the trait bound
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| ^^^^^^^^^^^^^^^^^^^^^^^ the trait `std::ops::Try` is not implemented for `()`
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note: required by `try_trait_generic`
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--> $DIR/try-operator-on-main.rs:20:1
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LL | fn try_trait_generic<T: Try>() -> T {
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| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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error[E0277]: the `?` operator can only be applied to values that implement `std::ops::Try`
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--> $DIR/try-operator-on-main.rs:22:5
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LL | ()?; //~ ERROR the `?` operator can only
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| ^^^ the `?` operator cannot be applied to type `()`
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= help: the trait `std::ops::Try` is not implemented for `()`
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= note: required by `std::ops::Try::into_result`
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error: aborting due to 4 previous errors
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For more information about this error, try `rustc --explain E0277`.
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