1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
use ::{List};
#[derive(Clone)]
pub struct ListIntoIter<T> {
list: List<T>
}
impl<T> Iterator for ListIntoIter<T> {
type Item = T;
fn next(&mut self) -> Option<Self::Item> {
self.list.pop_front()
}
fn size_hint(&self) -> (usize, Option<usize>) {
let len = self.list.len();
(len, Some(len))
}
}
impl<T> ExactSizeIterator for ListIntoIter<T> {}
impl<T> IntoIterator for List<T> {
type Item = T;
type IntoIter = ListIntoIter<Self::Item>;
fn into_iter(self) -> Self::IntoIter {
ListIntoIter{list: self}
}
}
#[test]
fn into_iter() {
let mut l = List::new();
for i in 1..10 {
l.push_back(i);
}
assert_eq!(l.len(), 9);
let mut acc = 0;
for v in l {
acc += v;
}
assert_eq!(acc, 45);
}