diff options
Diffstat (limited to 'third_party/rust/rayon/src/collections/binary_heap.rs')
-rw-r--r-- | third_party/rust/rayon/src/collections/binary_heap.rs | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/third_party/rust/rayon/src/collections/binary_heap.rs b/third_party/rust/rayon/src/collections/binary_heap.rs new file mode 100644 index 0000000000..fa903121af --- /dev/null +++ b/third_party/rust/rayon/src/collections/binary_heap.rs @@ -0,0 +1,120 @@ +//! This module contains the parallel iterator types for heaps +//! (`BinaryHeap<T>`). You will rarely need to interact with it directly +//! unless you have need to name one of the iterator types. + +use std::collections::BinaryHeap; + +use crate::iter::plumbing::*; +use crate::iter::*; + +use crate::vec; + +/// Parallel iterator over a binary heap +#[derive(Debug, Clone)] +pub struct IntoIter<T: Ord + Send> { + inner: vec::IntoIter<T>, +} + +impl<T: Ord + Send> IntoParallelIterator for BinaryHeap<T> { + type Item = T; + type Iter = IntoIter<T>; + + fn into_par_iter(self) -> Self::Iter { + IntoIter { + inner: Vec::from(self).into_par_iter(), + } + } +} + +delegate_indexed_iterator! { + IntoIter<T> => T, + impl<T: Ord + Send> +} + +/// Parallel iterator over an immutable reference to a binary heap +#[derive(Debug)] +pub struct Iter<'a, T: Ord + Sync> { + inner: vec::IntoIter<&'a T>, +} + +impl<'a, T: Ord + Sync> Clone for Iter<'a, T> { + fn clone(&self) -> Self { + Iter { + inner: self.inner.clone(), + } + } +} + +into_par_vec! { + &'a BinaryHeap<T> => Iter<'a, T>, + impl<'a, T: Ord + Sync> +} + +delegate_indexed_iterator! { + Iter<'a, T> => &'a T, + impl<'a, T: Ord + Sync + 'a> +} + +// `BinaryHeap` doesn't have a mutable `Iterator` + +/// Draining parallel iterator that moves out of a binary heap, +/// but keeps the total capacity. +#[derive(Debug)] +pub struct Drain<'a, T: Ord + Send> { + heap: &'a mut BinaryHeap<T>, +} + +impl<'a, T: Ord + Send> ParallelDrainFull for &'a mut BinaryHeap<T> { + type Iter = Drain<'a, T>; + type Item = T; + + fn par_drain(self) -> Self::Iter { + Drain { heap: self } + } +} + +impl<'a, T: Ord + Send> ParallelIterator for Drain<'a, T> { + type Item = T; + + fn drive_unindexed<C>(self, consumer: C) -> C::Result + where + C: UnindexedConsumer<Self::Item>, + { + bridge(self, consumer) + } + + fn opt_len(&self) -> Option<usize> { + Some(self.len()) + } +} + +impl<'a, T: Ord + Send> IndexedParallelIterator for Drain<'a, T> { + fn drive<C>(self, consumer: C) -> C::Result + where + C: Consumer<Self::Item>, + { + bridge(self, consumer) + } + + fn len(&self) -> usize { + self.heap.len() + } + + fn with_producer<CB>(self, callback: CB) -> CB::Output + where + CB: ProducerCallback<Self::Item>, + { + super::DrainGuard::new(self.heap) + .par_drain(..) + .with_producer(callback) + } +} + +impl<'a, T: Ord + Send> Drop for Drain<'a, T> { + fn drop(&mut self) { + if !self.heap.is_empty() { + // We must not have produced, so just call a normal drain to remove the items. + self.heap.drain(); + } + } +} |