use async_recursion::async_recursion; #[must_use] fn count_down<'life0, 'async_recursion>( foo: Option<&'life0 str>, ) -> ::core::pin::Pin< Box< dyn ::core::future::Future< Output = i32, > + 'async_recursion + ::core::marker::Send, >, > where 'life0: 'async_recursion, { Box::pin(async move { let _ = foo; 0 }) }