1 files changed, 80 insertions, 0 deletions
diff --git a/src/collections/hash_set.rs b/src/collections/hash_set.rs
new file mode 100644
index 0000000..b6ee1c1
--- /dev/null
+++ b/src/collections/hash_set.rs
@@ -0,0 +1,80 @@
+//! This module contains the parallel iterator types for hash sets
+//! (`HashSet<T>`). You will rarely need to interact with it directly
+//! unless you have need to name one of the iterator types.
+
+use std::collections::HashSet;
+use std::hash::{BuildHasher, Hash};
+use std::marker::PhantomData;
+
+use crate::iter::plumbing::*;
+use crate::iter::*;
+
+use crate::vec;
+
+/// Parallel iterator over a hash set
+#[derive(Debug)] // std doesn't Clone
+pub struct IntoIter<T: Hash + Eq + Send> {
+    inner: vec::IntoIter<T>,
+}
+
+into_par_vec! {
+    HashSet<T, S> => IntoIter<T>,
+    impl<T: Hash + Eq + Send, S: BuildHasher>
+}
+
+delegate_iterator! {
+    IntoIter<T> => T,
+    impl<T: Hash + Eq + Send>
+}
+
+/// Parallel iterator over an immutable reference to a hash set
+#[derive(Debug)]
+pub struct Iter<'a, T: Hash + Eq + Sync> {
+    inner: vec::IntoIter<&'a T>,
+}
+
+impl<'a, T: Hash + Eq + Sync> Clone for Iter<'a, T> {
+    fn clone(&self) -> Self {
+        Iter {
+            inner: self.inner.clone(),
+        }
+    }
+}
+
+into_par_vec! {
+    &'a HashSet<T, S> => Iter<'a, T>,
+    impl<'a, T: Hash + Eq + Sync, S: BuildHasher>
+}
+
+delegate_iterator! {
+    Iter<'a, T> => &'a T,
+    impl<'a, T: Hash + Eq + Sync + 'a>
+}
+
+// `HashSet` doesn't have a mutable `Iterator`
+
+/// Draining parallel iterator that moves out of a hash set,
+/// but keeps the total capacity.
+#[derive(Debug)]
+pub struct Drain<'a, T: Hash + Eq + Send> {
+    inner: vec::IntoIter<T>,
+    marker: PhantomData<&'a mut HashSet<T>>,
+}
+
+impl<'a, T: Hash + Eq + Send, S: BuildHasher> ParallelDrainFull for &'a mut HashSet<T, S> {
+    type Iter = Drain<'a, T>;
+    type Item = T;
+
+    fn par_drain(self) -> Self::Iter {
+        let vec: Vec<_> = self.drain().collect();
+        Drain {
+            inner: vec.into_par_iter(),
+            marker: PhantomData,
+        }
+    }
+}
+
+delegate_iterator! {
+    Drain<'_, T> => T,
+    impl<T: Hash + Eq + Send>
+}