phf/
set.rs

1//! An immutable set constructed at compile time.
2use core::fmt;
3use core::iter::FusedIterator;
4use core::iter::IntoIterator;
5
6use phf_shared::{PhfBorrow, PhfHash};
7
8use crate::{map, Map};
9
10/// An immutable set constructed at compile time.
11///
12/// ## Note
13///
14/// The fields of this struct are public so that they may be initialized by the
15/// `phf_set!` macro and code generation. They are subject to change at any
16/// time and should never be accessed directly.
17pub struct Set<T: 'static> {
18    #[doc(hidden)]
19    pub map: Map<T, ()>,
20}
21
22impl<T> fmt::Debug for Set<T>
23where
24    T: fmt::Debug,
25{
26    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
27        fmt.debug_set().entries(self).finish()
28    }
29}
30
31impl<T> Set<T> {
32    /// Returns the number of elements in the `Set`.
33    #[inline]
34    pub const fn len(&self) -> usize {
35        self.map.len()
36    }
37
38    /// Returns true if the `Set` contains no elements.
39    #[inline]
40    pub const fn is_empty(&self) -> bool {
41        self.len() == 0
42    }
43
44    /// Returns a reference to the set's internal static instance of the given
45    /// key.
46    ///
47    /// This can be useful for interning schemes.
48    pub fn get_key<U: ?Sized>(&self, key: &U) -> Option<&T>
49    where
50        U: Eq + PhfHash,
51        T: PhfBorrow<U>,
52    {
53        self.map.get_key(key)
54    }
55
56    /// Returns true if `value` is in the `Set`.
57    pub fn contains<U: ?Sized>(&self, value: &U) -> bool
58    where
59        U: Eq + PhfHash,
60        T: PhfBorrow<U>,
61    {
62        self.map.contains_key(value)
63    }
64
65    /// Returns an iterator over the values in the set.
66    ///
67    /// Values are returned in an arbitrary but fixed order.
68    pub fn iter(&self) -> Iter<'_, T> {
69        Iter {
70            iter: self.map.keys(),
71        }
72    }
73}
74
75impl<T> Set<T>
76where
77    T: Eq + PhfHash + PhfBorrow<T>,
78{
79    /// Returns true if `other` shares no elements with `self`.
80    pub fn is_disjoint(&self, other: &Set<T>) -> bool {
81        !self.iter().any(|value| other.contains(value))
82    }
83
84    /// Returns true if `other` contains all values in `self`.
85    pub fn is_subset(&self, other: &Set<T>) -> bool {
86        self.iter().all(|value| other.contains(value))
87    }
88
89    /// Returns true if `self` contains all values in `other`.
90    pub fn is_superset(&self, other: &Set<T>) -> bool {
91        other.is_subset(self)
92    }
93}
94
95impl<'a, T> IntoIterator for &'a Set<T> {
96    type Item = &'a T;
97    type IntoIter = Iter<'a, T>;
98
99    fn into_iter(self) -> Iter<'a, T> {
100        self.iter()
101    }
102}
103
104/// An iterator over the values in a `Set`.
105pub struct Iter<'a, T: 'static> {
106    iter: map::Keys<'a, T, ()>,
107}
108
109impl<'a, T> Clone for Iter<'a, T> {
110    #[inline]
111    fn clone(&self) -> Self {
112        Self {
113            iter: self.iter.clone(),
114        }
115    }
116}
117
118impl<'a, T> fmt::Debug for Iter<'a, T>
119where
120    T: fmt::Debug,
121{
122    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
123        f.debug_list().entries(self.clone()).finish()
124    }
125}
126
127impl<'a, T> Iterator for Iter<'a, T> {
128    type Item = &'a T;
129
130    fn next(&mut self) -> Option<&'a T> {
131        self.iter.next()
132    }
133
134    fn size_hint(&self) -> (usize, Option<usize>) {
135        self.iter.size_hint()
136    }
137}
138
139impl<'a, T> DoubleEndedIterator for Iter<'a, T> {
140    fn next_back(&mut self) -> Option<&'a T> {
141        self.iter.next_back()
142    }
143}
144
145impl<'a, T> ExactSizeIterator for Iter<'a, T> {}
146
147impl<'a, T> FusedIterator for Iter<'a, T> {}
phf/set.rs

phf/
set.rs
