1 #![feature(generic_associated_types)]
6 type Item<'a> where Self: 'a;
7 type Iter<'a>: Iterator<Item = Self::Item<'a>> where Self: 'a;
9 fn iter<'a>(&'a self) -> Self::Iter<'a>;
12 // Impl for struct type
13 impl<T> Iterable for Vec<T> {
14 type Item<'a> where T: 'a = <std::slice::Iter<'a, T> as Iterator>::Item;
15 type Iter<'a> where T: 'a = std::slice::Iter<'a, T>;
17 fn iter<'a>(&'a self) -> Self::Iter<'a> {
22 // Impl for a primitive type
23 impl<T> Iterable for [T] {
24 type Item<'a> where T: 'a = <std::slice::Iter<'a, T> as Iterator>::Item;
25 type Iter<'a> where T: 'a = std::slice::Iter<'a, T>;
27 fn iter<'a>(&'a self) -> Self::Iter<'a> {
32 fn make_iter<'a, I: Iterable + ?Sized>(it: &'a I) -> I::Iter<'a> {
36 fn get_first<'a, I: Iterable + ?Sized>(it: &'a I) -> Option<I::Item<'a>> {
41 let v = vec![1, 2, 3];
42 assert_eq!(v, make_iter(&v).copied().collect::<Vec<_>>());
43 assert_eq!(v, make_iter(&*v).copied().collect::<Vec<_>>());
44 assert_eq!(Some(&1), get_first(&v));
45 assert_eq!(Some(&1), get_first(&*v));