mirror of
https://github.com/rust-lang/rust
synced 2024-11-05 20:45:15 +00:00
73 lines
3.2 KiB
Text
73 lines
3.2 KiB
Text
error[E0038]: the trait `Foo` cannot be made into an object
|
|
--> $DIR/object-safety-no-static.rs:12:22
|
|
|
|
|
LL | fn diverges() -> Box<dyn Foo> {
|
|
| ^^^^^^^ `Foo` 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-safety-no-static.rs:9:8
|
|
|
|
|
LL | trait Foo {
|
|
| --- this trait cannot be made into an object...
|
|
LL | fn foo() {}
|
|
| ^^^ ...because associated function `foo` has no `self` parameter
|
|
= help: only type `Bar` implements the trait, consider using it directly instead
|
|
help: consider turning `foo` into a method by giving it a `&self` argument
|
|
|
|
|
LL | fn foo(&self) {}
|
|
| +++++
|
|
help: alternatively, consider constraining `foo` so it does not apply to trait objects
|
|
|
|
|
LL | fn foo() where Self: Sized {}
|
|
| +++++++++++++++++
|
|
|
|
error[E0038]: the trait `Foo` cannot be made into an object
|
|
--> $DIR/object-safety-no-static.rs:22:12
|
|
|
|
|
LL | let b: Box<dyn Foo> = Box::new(Bar);
|
|
| ^^^^^^^^^^^^ `Foo` 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-safety-no-static.rs:9:8
|
|
|
|
|
LL | trait Foo {
|
|
| --- this trait cannot be made into an object...
|
|
LL | fn foo() {}
|
|
| ^^^ ...because associated function `foo` has no `self` parameter
|
|
= help: only type `Bar` implements the trait, consider using it directly instead
|
|
help: consider turning `foo` into a method by giving it a `&self` argument
|
|
|
|
|
LL | fn foo(&self) {}
|
|
| +++++
|
|
help: alternatively, consider constraining `foo` so it does not apply to trait objects
|
|
|
|
|
LL | fn foo() where Self: Sized {}
|
|
| +++++++++++++++++
|
|
|
|
error[E0038]: the trait `Foo` cannot be made into an object
|
|
--> $DIR/object-safety-no-static.rs:22:27
|
|
|
|
|
LL | let b: Box<dyn Foo> = Box::new(Bar);
|
|
| ^^^^^^^^^^^^^ `Foo` 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-safety-no-static.rs:9:8
|
|
|
|
|
LL | trait Foo {
|
|
| --- this trait cannot be made into an object...
|
|
LL | fn foo() {}
|
|
| ^^^ ...because associated function `foo` has no `self` parameter
|
|
= help: only type `Bar` implements the trait, consider using it directly instead
|
|
= note: required for the cast from `Box<Bar>` to `Box<dyn Foo>`
|
|
help: consider turning `foo` into a method by giving it a `&self` argument
|
|
|
|
|
LL | fn foo(&self) {}
|
|
| +++++
|
|
help: alternatively, consider constraining `foo` so it does not apply to trait objects
|
|
|
|
|
LL | fn foo() where Self: Sized {}
|
|
| +++++++++++++++++
|
|
|
|
error: aborting due to 3 previous errors
|
|
|
|
For more information about this error, try `rustc --explain E0038`.
|