error[E0390]: cannot define inherent `impl` for primitive types --> $DIR/kinds-of-primitive-impl.rs:1:1 | LL | impl u8 { | ^^^^^^^ | = help: consider using an extension trait instead error[E0390]: cannot define inherent `impl` for primitive types --> $DIR/kinds-of-primitive-impl.rs:6:1 | LL | impl str { | ^^^^^^^^ | = help: consider using an extension trait instead error[E0390]: cannot define inherent `impl` for primitive types --> $DIR/kinds-of-primitive-impl.rs:12:1 | LL | impl char { | ^^^^^^^^^ | = help: consider using an extension trait instead error[E0390]: cannot define inherent `impl` for primitive types --> $DIR/kinds-of-primitive-impl.rs:21:1 | LL | impl &MyType { | ^^^^^^^^^^^^ | = help: consider using an extension trait instead = note: you could also try moving the reference to uses of `MyType` (such as `self`) within the implementation error: aborting due to 4 previous errors For more information about this error, try `rustc --explain E0390`.