1//! This module contains the parallel iterator types for hash sets
2//! (`HashSet<T>`). You will rarely need to interact with it directly
3//! unless you have need to name one of the iterator types.
4
5use std::collections::HashSet;
6use std::hash::{BuildHasher, Hash};
7use std::marker::PhantomData;
8
9use crate::iter::plumbing::*;
10use crate::iter::*;
11
12use crate::vec;
13
14/// Parallel iterator over a hash set
15#[derive(Debug)] // std doesn't Clone
16pub struct IntoIter<T: Hash + Eq + Send> {
17 inner: vec::IntoIter<T>,
18}
19
20into_par_vec! {
21 HashSet<T, S> => IntoIter<T>,
22 impl<T: Hash + Eq + Send, S: BuildHasher>
23}
24
25delegate_iterator! {
26 IntoIter<T> => T,
27 impl<T: Hash + Eq + Send>
28}
29
30/// Parallel iterator over an immutable reference to a hash set
31#[derive(Debug)]
32pub struct Iter<'a, T: Hash + Eq + Sync> {
33 inner: vec::IntoIter<&'a T>,
34}
35
36impl<'a, T: Hash + Eq + Sync> Clone for Iter<'a, T> {
37 fn clone(&self) -> Self {
38 Iter {
39 inner: self.inner.clone(),
40 }
41 }
42}
43
44into_par_vec! {
45 &'a HashSet<T, S> => Iter<'a, T>,
46 impl<'a, T: Hash + Eq + Sync, S: BuildHasher>
47}
48
49delegate_iterator! {
50 Iter<'a, T> => &'a T,
51 impl<'a, T: Hash + Eq + Sync + 'a>
52}
53
54// `HashSet` doesn't have a mutable `Iterator`
55
56/// Draining parallel iterator that moves out of a hash set,
57/// but keeps the total capacity.
58#[derive(Debug)]
59pub struct Drain<'a, T: Hash + Eq + Send> {
60 inner: vec::IntoIter<T>,
61 marker: PhantomData<&'a mut HashSet<T>>,
62}
63
64impl<'a, T: Hash + Eq + Send, S: BuildHasher> ParallelDrainFull for &'a mut HashSet<T, S> {
65 type Iter = Drain<'a, T>;
66 type Item = T;
67
68 fn par_drain(self) -> Self::Iter {
69 let vec: Vec<_> = self.drain().collect();
70 Drain {
71 inner: vec.into_par_iter(),
72 marker: PhantomData,
73 }
74 }
75}
76
77delegate_iterator! {
78 Drain<'_, T> => T,
79 impl<T: Hash + Eq + Send>
80}
81