1#![allow(dead_code)]
2
3use std::borrow::Borrow;
4
5/// Flat (Vec) backed set
6///
7/// This preserves insertion order
8#[derive(Clone, Debug, PartialEq, Eq)]
9pub(crate) struct FlatSet<T> {
10 inner: Vec<T>,
11}
12
13impl<T: PartialEq + Eq> FlatSet<T> {
14 pub(crate) fn new() -> Self {
15 Default::default()
16 }
17
18 pub(crate) fn insert(&mut self, value: T) -> bool {
19 for existing in &self.inner {
20 if *existing == value {
21 return false;
22 }
23 }
24 self.inner.push(value);
25 true
26 }
27
28 pub fn contains<Q: ?Sized>(&self, value: &Q) -> bool
29 where
30 T: Borrow<Q>,
31 Q: Eq,
32 {
33 for existing in &self.inner {
34 if existing.borrow() == value {
35 return true;
36 }
37 }
38 false
39 }
40
41 pub fn retain<F>(&mut self, f: F)
42 where
43 F: FnMut(&T) -> bool,
44 {
45 self.inner.retain(f);
46 }
47
48 pub(crate) fn is_empty(&self) -> bool {
49 self.inner.is_empty()
50 }
51
52 pub(crate) fn iter(&self) -> std::slice::Iter<'_, T> {
53 self.inner.iter()
54 }
55
56 pub fn sort_by_key<K, F>(&mut self, f: F)
57 where
58 F: FnMut(&T) -> K,
59 K: Ord,
60 {
61 self.inner.sort_by_key(f);
62 }
63}
64
65impl<T: PartialEq + Eq> Default for FlatSet<T> {
66 fn default() -> Self {
67 Self {
68 inner: Default::default(),
69 }
70 }
71}
72
73impl<T: PartialEq + Eq> IntoIterator for FlatSet<T> {
74 type Item = T;
75 type IntoIter = std::vec::IntoIter<T>;
76
77 fn into_iter(self) -> Self::IntoIter {
78 self.inner.into_iter()
79 }
80}
81
82impl<'s, T: PartialEq + Eq> IntoIterator for &'s FlatSet<T> {
83 type Item = &'s T;
84 type IntoIter = std::slice::Iter<'s, T>;
85
86 fn into_iter(self) -> Self::IntoIter {
87 self.inner.iter()
88 }
89}
90
91impl<T: PartialEq + Eq> Extend<T> for FlatSet<T> {
92 fn extend<I: IntoIterator<Item = T>>(&mut self, iter: I) {
93 for value: T in iter {
94 self.insert(value);
95 }
96 }
97}
98
99impl<T: PartialEq + Eq> FromIterator<T> for FlatSet<T> {
100 fn from_iter<I: IntoIterator<Item = T>>(iter: I) -> Self {
101 let mut set: FlatSet = Self::new();
102 for value: T in iter {
103 set.insert(value);
104 }
105 set
106 }
107}
108