1#[cfg(feature = "vec_map")]
2pub use vec_map::{Values, VecMap};
3
4#[cfg(not(feature = "vec_map"))]
5pub use self::vec_map::{Values, VecMap};
6
7#[cfg(not(feature = "vec_map"))]
8mod vec_map {
9 use std::collections::BTreeMap;
10 use std::collections::btree_map;
11 use std::fmt::{self, Debug, Formatter};
12
13 #[derive(Clone, Default, Debug)]
14 pub struct VecMap<V> {
15 inner: BTreeMap<usize, V>,
16 }
17
18 impl<V> VecMap<V> {
19 pub fn new() -> Self {
20 VecMap {
21 inner: Default::default(),
22 }
23 }
24
25 pub fn len(&self) -> usize { self.inner.len() }
26
27 pub fn is_empty(&self) -> bool { self.inner.is_empty() }
28
29 pub fn insert(&mut self, key: usize, value: V) -> Option<V> {
30 self.inner.insert(key, value)
31 }
32
33 pub fn values(&self) -> Values<V> { self.inner.values() }
34
35 pub fn iter(&self) -> Iter<V> {
36 Iter {
37 inner: self.inner.iter(),
38 }
39 }
40
41 pub fn contains_key(&self, key: usize) -> bool { self.inner.contains_key(&key) }
42
43 pub fn entry(&mut self, key: usize) -> Entry<V> { self.inner.entry(key) }
44
45 pub fn get(&self, key: usize) -> Option<&V> { self.inner.get(&key) }
46 }
47
48 pub type Values<'a, V> = btree_map::Values<'a, usize, V>;
49
50 pub type Entry<'a, V> = btree_map::Entry<'a, usize, V>;
51
52 #[derive(Clone)]
53 pub struct Iter<'a, V: 'a> {
54 inner: btree_map::Iter<'a, usize, V>,
55 }
56
57 impl<'a, V: 'a + Debug> Debug for Iter<'a, V> {
58 fn fmt(&self, f: &mut Formatter) -> fmt::Result {
59 f.debug_list().entries(self.inner.clone()).finish()
60 }
61 }
62
63 impl<'a, V: 'a> Iterator for Iter<'a, V> {
64 type Item = (usize, &'a V);
65
66 fn next(&mut self) -> Option<Self::Item> { self.inner.next().map(|(k, v)| (*k, v)) }
67 }
68
69 impl<'a, V: 'a> DoubleEndedIterator for Iter<'a, V> {
70 fn next_back(&mut self) -> Option<Self::Item> {
71 self.inner.next_back().map(|(k, v)| (*k, v))
72 }
73 }
74}