error[E0308]: mismatched types | |
--> $DIR/universal-mismatched-type.rs:4:5 | |
| | |
LL | fn foo(x: impl Debug) -> String { | |
| ------ expected `std::string::String` because of return type | |
LL | x | |
| ^ expected struct `std::string::String`, found type parameter | |
| | |
= note: expected type `std::string::String` | |
found type `impl Debug` | |
error: aborting due to previous error | |
For more information about this error, try `rustc --explain E0308`. |