// this will get a no-op Clone impl #[derive(Copy, Clone)] struct A { a: i32, b: i64 } // this will get a deep Clone impl #[derive(Copy, Clone)] struct B { a: i32, b: T } struct C; // not Copy or Clone #[derive(Clone)] struct D; // Clone but not Copy fn is_copy(_: T) {} fn is_clone(_: T) {} fn main() { // A can be copied and cloned is_copy(A { a: 1, b: 2 }); is_clone(A { a: 1, b: 2 }); // B can be copied and cloned is_copy(B { a: 1, b: 2 }); is_clone(B { a: 1, b: 2 }); // B cannot be copied or cloned is_copy(B { a: 1, b: C }); //~ ERROR Copy is_clone(B { a: 1, b: C }); //~ ERROR Clone // B can be cloned but not copied is_copy(B { a: 1, b: D }); //~ ERROR Copy is_clone(B { a: 1, b: D }); }