// check-pass // edition: 2021 #![feature(async_fn_in_trait)] #![feature(return_position_impl_trait_in_trait)] #![allow(incomplete_features)] use std::future::Future; trait MyTrait { #[allow(async_fn_in_trait)] async fn foo(&self) -> i32; } impl MyTrait for i32 { fn foo(&self) -> impl Future { async { *self } } } fn main() {}