//@ check-pass //@ edition: 2021 // issue: 113796 trait AsyncLendingIterator { type Item<'a> where Self: 'a; #[allow(async_fn_in_trait)] async fn next(&mut self) -> Option>; } struct Lend(I); impl AsyncLendingIterator for Lend { type Item<'a> = &'a I where Self: 'a; // Checking that the synthetic `::next()` GAT // is well-formed requires being able to assume the WF types of `next`. async fn next(&mut self) -> Option> { todo!() } } fn main() {}