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error[E0038]: the trait `Foo` cannot be made into an object
--> $DIR/arbitrary-self-types-dyn-incompatible.rs:33:32
|
LL | fn foo(self: &Rc<Self>) -> usize;
| --------- help: consider changing method `foo`'s `self` parameter to be `&self`: `&Self`
...
LL | let x = Rc::new(5usize) as Rc<dyn Foo>;
| ^^^^^^^^^^^ `Foo` cannot be made into an object
|
note: for a trait to be "dyn-compatible" 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/arbitrary-self-types-dyn-incompatible.rs:8:18
|
LL | trait Foo {
| --- this trait cannot be made into an object...
LL | fn foo(self: &Rc<Self>) -> usize;
| ^^^^^^^^^ ...because method `foo`'s `self` parameter cannot be dispatched on
= help: only type `usize` implements the trait, consider using it directly instead
error[E0038]: the trait `Foo` cannot be made into an object
--> $DIR/arbitrary-self-types-dyn-incompatible.rs:33:13
|
LL | fn foo(self: &Rc<Self>) -> usize;
| --------- help: consider changing method `foo`'s `self` parameter to be `&self`: `&Self`
...
LL | let x = Rc::new(5usize) as Rc<dyn Foo>;
| ^^^^^^^^^^^^^^^ `Foo` cannot be made into an object
|
note: for a trait to be "dyn-compatible" 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/arbitrary-self-types-dyn-incompatible.rs:8:18
|
LL | trait Foo {
| --- this trait cannot be made into an object...
LL | fn foo(self: &Rc<Self>) -> usize;
| ^^^^^^^^^ ...because method `foo`'s `self` parameter cannot be dispatched on
= help: only type `usize` implements the trait, consider using it directly instead
= note: required for the cast from `Rc<usize>` to `Rc<dyn Foo>`
error: aborting due to 2 previous errors
For more information about this error, try `rustc --explain E0038`.
|
