error[E0562]: `impl Trait` only allowed in function and inherent method return types, not in `impl` method return types --> $DIR/fn-not-async-err2.rs:15:22 | LL | fn foo(&self) -> impl Future { | ^^^^^^^^^^^^^^^^^^^^^^^^^ | = note: see issue #91611 for more information = help: add `#![feature(return_position_impl_trait_in_trait)]` to the crate attributes to enable error: aborting due to previous error For more information about this error, try `rustc --explain E0562`.