1 #![feature(auto_traits)] 2 #![feature(negative_impls)] 3 #![allow(bare_trait_objects)] 4 5 auto trait Auto {} 6 main()7fn main() { 8 let _: Box<((Auto)) + Auto>; 9 //~^ ERROR expected a path on the left-hand side of `+`, not `((Auto))` 10 let _: Box<(Auto + Auto) + Auto>; 11 //~^ ERROR expected a path on the left-hand side of `+`, not `(Auto + Auto)` 12 let _: Box<(Auto +) + Auto>; 13 //~^ ERROR expected a path on the left-hand side of `+`, not `(Auto)` 14 let _: Box<(dyn Auto) + Auto>; 15 //~^ ERROR expected a path on the left-hand side of `+`, not `(dyn Auto)` 16 } 17