small_ord_set/
map.rs

1use std::borrow::Borrow;
2use std::cmp::Ordering;
3use std::fmt::{self, Debug};
4use std::hash::{Hash, Hasher};
5
6use smallvec::Array;
7
8use crate::SmallOrdSet;
9
10/// A key-value pair. When used as the element type of a `SmallOrdSet`, it
11/// acts as a map.
12///
13/// Comparisons of this type only look at the key. This property also applies
14/// to `SmallOrdSet<KeyValuePair>`.
15#[derive(Copy, Clone, Default)]
16pub struct KeyValuePair<K, V> {
17    /// The key, used for checking ordering and equality.
18    pub key: K,
19    /// The value.
20    pub value: V,
21}
22
23impl<A, K, V> SmallOrdSet<A>
24where
25    A: Array<Item = KeyValuePair<K, V>>,
26    K: Ord,
27{
28    /// Inserts a key-value pair into the map.
29    ///
30    /// This function is a convenience wrapper around [`insert`](struct.SmallOrdSet.html#method.insert)
31    pub fn insert_value(&mut self, key: K, value: V) -> bool {
32        self.insert(KeyValuePair { key, value })
33    }
34
35    /// Replaces a key-value pair in the map.
36    ///
37    /// This function is a convenience wrapper around [`replace`](struct.SmallOrdSet.html#method.replace)
38    pub fn replace_value(&mut self, key: K, value: V) -> Option<V> {
39        self.replace(KeyValuePair { key, value })
40            .map(|kvp| kvp.value)
41    }
42
43    /// Removes a key-value pair from the map.
44    ///
45    /// This function is a convenience wrapper around [`remove`](struct.SmallOrdSet.html#method.remove)
46    pub fn remove_value(&mut self, key: &K) -> Option<V> {
47        self.remove(key).map(|kvp| kvp.value)
48    }
49
50    /// Gets a reference to the value for a key in the map.
51    ///
52    /// This function is a convenience wrapper around [`get`](struct.SmallOrdSet.html#method.get)
53    pub fn get_value<'a>(&'a self, key: &K) -> Option<&'a V>
54    where
55        K: 'a,
56    {
57        self.get(key).map(|kvp| &kvp.value)
58    }
59
60    /// Gets a mutable reference to the value for a key in the map.
61    ///
62    /// This function is a convenience wrapper around [`get_mut`](struct.SmallOrdSet.html#method.get_mut).
63    /// Unlike `get_mut`, it prevents changing the order of elements by only returning the value part of
64    /// the pair.
65    pub fn get_value_mut<'a>(&'a mut self, key: &K) -> Option<&'a mut V>
66    where
67        K: 'a,
68    {
69        self.get_mut(key).map(|kvp| &mut kvp.value)
70    }
71
72    /// Get an iterator over all keys in the map.
73    pub fn keys<'a>(&'a self) -> impl Iterator<Item = &'a K> + Clone
74    where
75        KeyValuePair<K, V>: 'a,
76    {
77        self.iter().map(|kvp| &kvp.key)
78    }
79
80    /// Get an iterator over all values in the map.
81    pub fn values<'a>(&'a self) -> impl Iterator<Item = &'a V> + Clone
82    where
83        KeyValuePair<K, V>: 'a,
84    {
85        self.iter().map(|kvp| &kvp.value)
86    }
87}
88
89impl<K: Hash, V> Hash for KeyValuePair<K, V> {
90    fn hash<H: Hasher>(&self, state: &mut H) {
91        self.key.hash(state)
92    }
93}
94
95impl<K: PartialEq, V> PartialEq for KeyValuePair<K, V> {
96    fn eq(&self, other: &Self) -> bool {
97        PartialEq::eq(&self.key, &other.key)
98    }
99}
100
101impl<K: Eq, V> Eq for KeyValuePair<K, V> {}
102
103impl<K: PartialOrd, V> PartialOrd for KeyValuePair<K, V> {
104    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
105        PartialOrd::partial_cmp(&self.key, &other.key)
106    }
107}
108
109impl<K: Ord, V> Ord for KeyValuePair<K, V> {
110    fn cmp(&self, other: &Self) -> Ordering {
111        Ord::cmp(&self.key, &other.key)
112    }
113}
114
115impl<K: Debug, V: Debug> Debug for KeyValuePair<K, V> {
116    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
117        write!(f, "{:?}: {:?}", self.key, self.value)
118    }
119}
120
121impl<K, V> Borrow<K> for KeyValuePair<K, V> {
122    fn borrow(&self) -> &K {
123        &self.key
124    }
125}
small_ord_set/map.rs

small_ord_set/
map.rs
