1#[cfg(feature = "std")]
2#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
3#[macro_export]
4/// Create an `IndexMap` from a list of key-value pairs
5///
6/// ## Example
7///
8/// ```
9/// use indexmap::indexmap;
10///
11/// let map = indexmap!{
12/// "a" => 1,
13/// "b" => 2,
14/// };
15/// assert_eq!(map["a"], 1);
16/// assert_eq!(map["b"], 2);
17/// assert_eq!(map.get("c"), None);
18///
19/// // "a" is the first key
20/// assert_eq!(map.keys().next(), Some(&"a"));
21/// ```
22macro_rules! indexmap {
23 ($($key:expr => $value:expr,)+) => { $crate::indexmap!($($key => $value),+) };
24 ($($key:expr => $value:expr),*) => {
25 {
26 // Note: `stringify!($key)` is just here to consume the repetition,
27 // but we throw away that string literal during constant evaluation.
28 const CAP: usize = <[()]>::len(&[$({ stringify!($key); }),*]);
29 let mut map = $crate::IndexMap::with_capacity(CAP);
30 $(
31 map.insert($key, $value);
32 )*
33 map
34 }
35 };
36}
37
38#[cfg(feature = "std")]
39#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
40#[macro_export]
41/// Create an `IndexSet` from a list of values
42///
43/// ## Example
44///
45/// ```
46/// use indexmap::indexset;
47///
48/// let set = indexset!{
49/// "a",
50/// "b",
51/// };
52/// assert!(set.contains("a"));
53/// assert!(set.contains("b"));
54/// assert!(!set.contains("c"));
55///
56/// // "a" is the first value
57/// assert_eq!(set.iter().next(), Some(&"a"));
58/// ```
59macro_rules! indexset {
60 ($($value:expr,)+) => { $crate::indexset!($($value),+) };
61 ($($value:expr),*) => {
62 {
63 // Note: `stringify!($value)` is just here to consume the repetition,
64 // but we throw away that string literal during constant evaluation.
65 const CAP: usize = <[()]>::len(&[$({ stringify!($value); }),*]);
66 let mut set = $crate::IndexSet::with_capacity(CAP);
67 $(
68 set.insert($value);
69 )*
70 set
71 }
72 };
73}
74
75// generate all the Iterator methods by just forwarding to the underlying
76// self.iter and mapping its element.
77macro_rules! iterator_methods {
78 // $map_elt is the mapping function from the underlying iterator's element
79 // same mapping function for both options and iterators
80 ($map_elt:expr) => {
81 fn next(&mut self) -> Option<Self::Item> {
82 self.iter.next().map($map_elt)
83 }
84
85 fn size_hint(&self) -> (usize, Option<usize>) {
86 self.iter.size_hint()
87 }
88
89 fn count(self) -> usize {
90 self.iter.len()
91 }
92
93 fn nth(&mut self, n: usize) -> Option<Self::Item> {
94 self.iter.nth(n).map($map_elt)
95 }
96
97 fn last(mut self) -> Option<Self::Item> {
98 self.next_back()
99 }
100
101 fn collect<C>(self) -> C
102 where
103 C: FromIterator<Self::Item>,
104 {
105 // NB: forwarding this directly to standard iterators will
106 // allow it to leverage unstable traits like `TrustedLen`.
107 self.iter.map($map_elt).collect()
108 }
109 };
110}
111
112macro_rules! double_ended_iterator_methods {
113 // $map_elt is the mapping function from the underlying iterator's element
114 // same mapping function for both options and iterators
115 ($map_elt:expr) => {
116 fn next_back(&mut self) -> Option<Self::Item> {
117 self.iter.next_back().map($map_elt)
118 }
119
120 fn nth_back(&mut self, n: usize) -> Option<Self::Item> {
121 self.iter.nth_back(n).map($map_elt)
122 }
123 };
124}
125
126// generate `ParallelIterator` methods by just forwarding to the underlying
127// self.entries and mapping its elements.
128#[cfg(any(feature = "rayon", feature = "rustc-rayon"))]
129macro_rules! parallel_iterator_methods {
130 // $map_elt is the mapping function from the underlying iterator's element
131 ($map_elt:expr) => {
132 fn drive_unindexed<C>(self, consumer: C) -> C::Result
133 where
134 C: UnindexedConsumer<Self::Item>,
135 {
136 self.entries
137 .into_par_iter()
138 .map($map_elt)
139 .drive_unindexed(consumer)
140 }
141
142 // NB: This allows indexed collection, e.g. directly into a `Vec`, but the
143 // underlying iterator must really be indexed. We should remove this if we
144 // start having tombstones that must be filtered out.
145 fn opt_len(&self) -> Option<usize> {
146 Some(self.entries.len())
147 }
148 };
149}
150
151// generate `IndexedParallelIterator` methods by just forwarding to the underlying
152// self.entries and mapping its elements.
153#[cfg(any(feature = "rayon", feature = "rustc-rayon"))]
154macro_rules! indexed_parallel_iterator_methods {
155 // $map_elt is the mapping function from the underlying iterator's element
156 ($map_elt:expr) => {
157 fn drive<C>(self, consumer: C) -> C::Result
158 where
159 C: Consumer<Self::Item>,
160 {
161 self.entries.into_par_iter().map($map_elt).drive(consumer)
162 }
163
164 fn len(&self) -> usize {
165 self.entries.len()
166 }
167
168 fn with_producer<CB>(self, callback: CB) -> CB::Output
169 where
170 CB: ProducerCallback<Self::Item>,
171 {
172 self.entries
173 .into_par_iter()
174 .map($map_elt)
175 .with_producer(callback)
176 }
177 };
178}
179