31febc684b
```
error[E0277]: `?` couldn't convert the error: `E: std::error::Error` is not satisfied
--> $DIR/bad-question-mark-on-trait-object.rs:7:13
|
LL | fn foo() -> Result<(), Box<dyn std::error::Error>> {
| -------------------------------------- required `E: std::error::Error` because of this
LL | Ok(bar()?)
| -----^ the trait `std::error::Error` is not implemented for `E`
| |
| this has type `Result<_, E>`
|
note: `E` needs to implement `std::error::Error`
--> $DIR/bad-question-mark-on-trait-object.rs:1:1
|
LL | struct E;
| ^^^^^^^^
= note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait
= note: required for `Box<dyn std::error::Error>` to implement `From<E>`
error[E0277]: `?` couldn't convert the error to `X`
--> $DIR/bad-question-mark-on-trait-object.rs:18:13
|
LL | fn bat() -> Result<(), X> {
| ------------- expected `X` because of this
LL | Ok(bar()?)
| -----^ the trait `From<E>` is not implemented for `X`
| |
| this can't be annotated with `?` because it has type `Result<_, E>`
|
note: `X` needs to implement `From<E>`
--> $DIR/bad-question-mark-on-trait-object.rs:4:1
|
LL | struct X;
| ^^^^^^^^
note: alternatively, `E` needs to implement `Into<X>`
--> $DIR/bad-question-mark-on-trait-object.rs:1:1
|
LL | struct E;
| ^^^^^^^^
= note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait
```
29 lines
1.3 KiB
Rust
29 lines
1.3 KiB
Rust
struct E;
|
|
//~^ NOTE `E` needs to implement `std::error::Error`
|
|
//~| NOTE alternatively, `E` needs to implement `Into<X>`
|
|
struct X; //~ NOTE `X` needs to implement `From<E>`
|
|
|
|
fn foo() -> Result<(), Box<dyn std::error::Error>> { //~ NOTE required `E: std::error::Error` because of this
|
|
Ok(bar()?)
|
|
//~^ ERROR `?` couldn't convert the error: `E: std::error::Error` is not satisfied
|
|
//~| NOTE the trait `std::error::Error` is not implemented for `E`
|
|
//~| NOTE the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait
|
|
//~| NOTE required for `Box<dyn std::error::Error>` to implement `From<E>`
|
|
//~| NOTE this has type `Result<_, E>`
|
|
//~| NOTE in this expansion
|
|
//~| NOTE in this expansion
|
|
//~| NOTE in this expansion
|
|
}
|
|
fn bat() -> Result<(), X> { //~ NOTE expected `X` because of this
|
|
Ok(bar()?)
|
|
//~^ ERROR `?` couldn't convert the error to `X`
|
|
//~| NOTE the trait `From<E>` is not implemented for `X`
|
|
//~| NOTE this can't be annotated with `?` because it has type `Result<_, E>`
|
|
//~| NOTE the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait
|
|
//~| NOTE in this expansion
|
|
//~| NOTE in this expansion
|
|
}
|
|
fn bar() -> Result<(), E> {
|
|
Err(E)
|
|
}
|
|
fn main() {}
|