//@ revisions: old new //@[old] edition:2015 //@[new] edition:2021 //@[new] run-rustfix #![deny(bare_trait_objects)] fn ord_prefer_dot(s: String) -> impl Ord { //[new]~^ ERROR expected a type, found a trait //[old]~^^ ERROR the trait `Ord` cannot be made into an object //[old]~| ERROR trait objects without an explicit `dyn` are deprecated //[old]~| WARNING this is accepted in the current edition (Rust 2015) (s.starts_with("."), s) } fn main() { let _ = ord_prefer_dot(String::new()); }