//@ check-pass //@ edition:2018 struct Foo<'a>(&'a ()); impl<'a> Foo<'a> { async fn foo<'b>(self: &'b Foo<'a>) -> &() { self.0 } } type Alias = Foo<'static>; impl Alias { async fn bar<'a>(self: &Alias, arg: &'a ()) -> &() { arg } } fn main() {}