3 #![feature(generic_associated_types)]
4 #![feature(type_alias_impl_trait)]
6 use std::future::Future;
8 trait SearchableResource<Criteria> {
12 trait SearchableResourceExt<Criteria>: SearchableResource<Criteria> {
13 type Future<'f, A: 'f + ?Sized, B: 'f>: Future<Output = Result<Vec<A::SearchResult>, ()>> + 'f
15 A: SearchableResource<B>,
18 fn search<'c>(&'c self, client: &'c ()) -> Self::Future<'c, Self, Criteria>;
21 type SearchFutureTy<'f, A, B: 'f>
23 A: SearchableResource<B> + ?Sized + 'f,
24 = impl Future<Output = Result<Vec<A::SearchResult>, ()>> + 'f;
25 impl<T, Criteria> SearchableResourceExt<Criteria> for T
27 T: SearchableResource<Criteria>,
29 type Future<'f, A, B: 'f> = SearchFutureTy<'f, A, B>
31 A: SearchableResource<B> + ?Sized + 'f,
34 fn search<'c>(&'c self, _client: &'c ()) -> Self::Future<'c, Self, Criteria> {
35 async move { todo!() }
36 //~^ ERROR: the size for values of type `A` cannot be known at compilation time