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