1 trait Add<Rhs=Self> { 2 type Output; 3 } 4 5 impl Add for i32 { 6 type Output = i32; 7 } 8 main()9 fn main() { 10 let x = &10 as &dyn Add; 11 //~^ ERROR E0393 12 //~| ERROR E0191 13 } 14