// edition: 2021 #![feature(async_fn_in_trait)] #![feature(return_position_impl_trait_in_trait)] #![allow(incomplete_features)] use std::future::Future; use std::pin::Pin; trait MyTrait { fn foo(&self) -> Pin + '_>>; } impl MyTrait for i32 { async fn foo(&self) -> i32 { //~^ ERROR method `foo` has an incompatible type for trait *self } } fn main() {}