mirror of
https://github.com/rust-lang/rust.git
synced 2024-11-23 15:23:46 +00:00
42 lines
1.9 KiB
Plaintext
42 lines
1.9 KiB
Plaintext
error[E0038]: the trait `Trait` cannot be made into an object
|
|
--> $DIR/object-unsafe-trait-should-use-where-sized.rs:9:12
|
|
|
|
|
LL | fn bar(x: &dyn Trait) {}
|
|
| ^^^^^^^^^ `Trait` 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-where-sized.rs:5:8
|
|
|
|
|
LL | trait Trait {
|
|
| ----- this trait cannot be made into an object...
|
|
LL | fn foo() where Self: Other, { }
|
|
| ^^^ ...because associated function `foo` has no `self` parameter
|
|
LL | fn bar(self: ()) {}
|
|
| ^^ ...because method `bar`'s `self` parameter cannot be dispatched on
|
|
help: consider turning `foo` into a method by giving it a `&self` argument
|
|
|
|
|
LL | fn foo(&self) where Self: Other, { }
|
|
| +++++
|
|
help: alternatively, consider constraining `foo` so it does not apply to trait objects
|
|
|
|
|
LL | fn foo() where Self: Other, Self: Sized { }
|
|
| ~~~~~~~~~~~~~
|
|
help: consider changing method `bar`'s `self` parameter to be `&self`
|
|
|
|
|
LL | fn bar(self: &Self) {}
|
|
| ~~~~~
|
|
|
|
error[E0307]: invalid `self` parameter type: ()
|
|
--> $DIR/object-unsafe-trait-should-use-where-sized.rs:6:18
|
|
|
|
|
LL | fn bar(self: ()) {}
|
|
| ^^
|
|
|
|
|
= note: type of `self` must be `Self` or a type that dereferences to it
|
|
= help: consider changing to `self`, `&self`, `&mut self`, `self: Box<Self>`, `self: Rc<Self>`, `self: Arc<Self>`, or `self: Pin<P>` (where P is one of the previous types except `Self`)
|
|
|
|
error: aborting due to 2 previous errors
|
|
|
|
Some errors have detailed explanations: E0038, E0307.
|
|
For more information about an error, try `rustc --explain E0038`.
|