mirror of
https://github.com/rust-lang/rust.git
synced 2024-11-23 15:23:46 +00:00
66 lines
2.5 KiB
Plaintext
66 lines
2.5 KiB
Plaintext
error: associated item referring to unboxed trait object for its own trait
|
|
--> $DIR/object-unsafe-trait-should-use-self-2021.rs:4:13
|
|
|
|
|
LL | trait A: Sized {
|
|
| - in this trait
|
|
LL | fn f(a: dyn A) -> dyn A;
|
|
| ^^^^^ ^^^^^
|
|
|
|
|
help: you might have meant to use `Self` to refer to the implementing type
|
|
|
|
|
LL | fn f(a: Self) -> Self;
|
|
| ~~~~ ~~~~
|
|
|
|
error[E0038]: the trait `A` cannot be made into an object
|
|
--> $DIR/object-unsafe-trait-should-use-self-2021.rs:4:13
|
|
|
|
|
LL | fn f(a: dyn A) -> dyn A;
|
|
| ^^^^^ `A` cannot be made into an object
|
|
|
|
|
note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
|
|
--> $DIR/object-unsafe-trait-should-use-self-2021.rs:3:10
|
|
|
|
|
LL | trait A: Sized {
|
|
| - ^^^^^ ...because it requires `Self: Sized`
|
|
| |
|
|
| this trait cannot be made into an object...
|
|
|
|
error: associated item referring to unboxed trait object for its own trait
|
|
--> $DIR/object-unsafe-trait-should-use-self-2021.rs:9:13
|
|
|
|
|
LL | trait B {
|
|
| - in this trait
|
|
LL | fn f(a: dyn B) -> dyn B;
|
|
| ^^^^^ ^^^^^
|
|
|
|
|
help: you might have meant to use `Self` to refer to the implementing type
|
|
|
|
|
LL | fn f(a: Self) -> Self;
|
|
| ~~~~ ~~~~
|
|
|
|
error[E0038]: the trait `B` cannot be made into an object
|
|
--> $DIR/object-unsafe-trait-should-use-self-2021.rs:9:13
|
|
|
|
|
LL | fn f(a: dyn B) -> dyn B;
|
|
| ^^^^^ `B` cannot be made into an object
|
|
|
|
|
note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
|
|
--> $DIR/object-unsafe-trait-should-use-self-2021.rs:9:8
|
|
|
|
|
LL | trait B {
|
|
| - this trait cannot be made into an object...
|
|
LL | fn f(a: dyn B) -> dyn B;
|
|
| ^ ...because associated function `f` has no `self` parameter
|
|
help: consider turning `f` into a method by giving it a `&self` argument
|
|
|
|
|
LL | fn f(&self, a: dyn B) -> dyn B;
|
|
| ++++++
|
|
help: alternatively, consider constraining `f` so it does not apply to trait objects
|
|
|
|
|
LL | fn f(a: dyn B) -> dyn B where Self: Sized;
|
|
| +++++++++++++++++
|
|
|
|
error: aborting due to 4 previous errors
|
|
|
|
For more information about this error, try `rustc --explain E0038`.
|