mirror of
https://github.com/rust-lang/rust.git
synced 2024-12-03 04:04:06 +00:00
58 lines
1.8 KiB
Plaintext
58 lines
1.8 KiB
Plaintext
error[E0782]: expected a type, found a trait
|
|
--> $DIR/ice-unsized-fn-params.rs:13:13
|
|
|
|
|
LL | fn g(b: B) -> B;
|
|
| ^
|
|
|
|
|
= note: `B` it is dyn-incompatible, so it can't be `dyn`
|
|
help: use a new generic type parameter, constrained by `B`
|
|
|
|
|
LL | fn g<T: B>(b: T) -> B;
|
|
| ++++++ ~
|
|
help: you can also use an opaque type, but users won't be able to specify the type parameter when calling the `fn`, having to rely exclusively on type inference
|
|
|
|
|
LL | fn g(b: impl B) -> B;
|
|
| ++++
|
|
|
|
error[E0782]: expected a type, found a trait
|
|
--> $DIR/ice-unsized-fn-params.rs:13:19
|
|
|
|
|
LL | fn g(b: B) -> B;
|
|
| ^
|
|
|
|
|
help: `B` is dyn-incompatible, use `impl B` to return an opaque type, as long as you return a single underlying type
|
|
|
|
|
LL | fn g(b: B) -> impl B;
|
|
| ++++
|
|
|
|
error[E0782]: expected a type, found a trait
|
|
--> $DIR/ice-unsized-fn-params.rs:7:13
|
|
|
|
|
LL | fn f(a: A) -> A;
|
|
| ^
|
|
|
|
|
= note: `A` it is dyn-incompatible, so it can't be `dyn`
|
|
help: use a new generic type parameter, constrained by `A`
|
|
|
|
|
LL | fn f<T: A>(a: T) -> A;
|
|
| ++++++ ~
|
|
help: you can also use an opaque type, but users won't be able to specify the type parameter when calling the `fn`, having to rely exclusively on type inference
|
|
|
|
|
LL | fn f(a: impl A) -> A;
|
|
| ++++
|
|
|
|
error[E0782]: expected a type, found a trait
|
|
--> $DIR/ice-unsized-fn-params.rs:7:19
|
|
|
|
|
LL | fn f(a: A) -> A;
|
|
| ^
|
|
|
|
|
help: `A` is dyn-incompatible, use `impl A` to return an opaque type, as long as you return a single underlying type
|
|
|
|
|
LL | fn f(a: A) -> impl A;
|
|
| ++++
|
|
|
|
error: aborting due to 4 previous errors
|
|
|
|
For more information about this error, try `rustc --explain E0782`.
|