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error[E0277]: `?` couldn't convert the error to `()`
--> $DIR/issue-32709.rs:4:11
|
LL | fn a() -> Result<i32, ()> {
| --------------- expected `()` because of this
LL | Err(5)?;
| ------^ the trait `From<{integer}>` is not implemented for `()`, which is required by `Result<i32, ()>: FromResidual<Result<Infallible, {integer}>>`
| |
| this can't be annotated with `?` because it has type `Result<_, {integer}>`
|
= note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait
= help: the following other types implement trait `From<T>`:
<(T,) as From<[T; 1]>>
<(T, T) as From<[T; 2]>>
<(T, T, T) as From<[T; 3]>>
<(T, T, T, T) as From<[T; 4]>>
<(T, T, T, T, T) as From<[T; 5]>>
<(T, T, T, T, T, T) as From<[T; 6]>>
<(T, T, T, T, T, T, T) as From<[T; 7]>>
<(T, T, T, T, T, T, T, T) as From<[T; 8]>>
and 4 others
= note: required for `Result<i32, ()>` to implement `FromResidual<Result<Infallible, {integer}>>`
error: aborting due to 1 previous error
For more information about this error, try `rustc --explain E0277`.
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