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error[E0038]: the trait `Foo` cannot be made into an object
--> $DIR/object-safety.rs:17:33
|
LL | let i = Box::new(42_u32) as 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.rs:7:8
|
LL | trait Foo {
| --- this trait cannot be made into an object...
LL | fn baz(&self) -> impl Debug;
| ^^^ ...because method `baz` references an `impl Trait` type in its return type
= help: consider moving `baz` to another trait
error[E0038]: the trait `Foo` cannot be made into an object
--> $DIR/object-safety.rs:20:13
|
LL | let s = i.baz();
| ^^^^^^^ `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.rs:7:8
|
LL | trait Foo {
| --- this trait cannot be made into an object...
LL | fn baz(&self) -> impl Debug;
| ^^^ ...because method `baz` references an `impl Trait` type in its return type
= help: consider moving `baz` to another trait
error[E0038]: the trait `Foo` cannot be made into an object
--> $DIR/object-safety.rs:17:13
|
LL | let i = Box::new(42_u32) as 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.rs:7:8
|
LL | trait Foo {
| --- this trait cannot be made into an object...
LL | fn baz(&self) -> impl Debug;
| ^^^ ...because method `baz` references an `impl Trait` type in its return type
= help: consider moving `baz` to another trait
= note: required for `Box<u32>` to implement `CoerceUnsized<Box<dyn Foo>>`
= note: required by cast to type `Box<dyn Foo>`
error: aborting due to 3 previous errors
For more information about this error, try `rustc --explain E0038`.
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