2019-04-17 21:50:50 -05:00
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error[E0277]: `?` couldn't convert the error to `()`
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2019-04-17 20:30:26 -05:00
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--> $DIR/try-on-option.rs:7:6
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2017-09-22 10:24:06 -05:00
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2019-03-09 06:03:44 -06:00
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LL | x?;
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2019-04-17 20:30:26 -05:00
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| ^ the trait `std::convert::From<std::option::NoneError>` is not implemented for `()`
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2017-09-22 10:24:06 -05:00
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2019-05-17 14:18:56 -05:00
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= note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait
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2017-09-22 10:24:06 -05:00
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= note: required by `std::convert::From::from`
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2018-03-28 04:25:52 -05:00
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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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2018-12-25 09:56:47 -06:00
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--> $DIR/try-on-option.rs:13:5
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2017-09-22 10:24:06 -05:00
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2019-11-24 15:29:40 -06:00
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LL | / fn bar() -> u32 {
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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 a 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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2017-09-22 10:24:06 -05:00
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= help: the trait `std::ops::Try` is not implemented for `u32`
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= note: required by `std::ops::Try::from_error`
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error: aborting due to 2 previous errors
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2018-03-03 08:59:40 -06:00
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For more information about this error, try `rustc --explain E0277`.
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