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-rw-r--r--vendor/rayon/src/iter/find.rs120
1 files changed, 120 insertions, 0 deletions
diff --git a/vendor/rayon/src/iter/find.rs b/vendor/rayon/src/iter/find.rs
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+++ b/vendor/rayon/src/iter/find.rs
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+use super::plumbing::*;
+use super::*;
+use std::sync::atomic::{AtomicBool, Ordering};
+
+pub(super) fn find<I, P>(pi: I, find_op: P) -> Option<I::Item>
+where
+ I: ParallelIterator,
+ P: Fn(&I::Item) -> bool + Sync,
+{
+ let found = AtomicBool::new(false);
+ let consumer = FindConsumer::new(&find_op, &found);
+ pi.drive_unindexed(consumer)
+}
+
+struct FindConsumer<'p, P> {
+ find_op: &'p P,
+ found: &'p AtomicBool,
+}
+
+impl<'p, P> FindConsumer<'p, P> {
+ fn new(find_op: &'p P, found: &'p AtomicBool) -> Self {
+ FindConsumer { find_op, found }
+ }
+}
+
+impl<'p, T, P: 'p> Consumer<T> for FindConsumer<'p, P>
+where
+ T: Send,
+ P: Fn(&T) -> bool + Sync,
+{
+ type Folder = FindFolder<'p, T, P>;
+ type Reducer = FindReducer;
+ type Result = Option<T>;
+
+ fn split_at(self, _index: usize) -> (Self, Self, Self::Reducer) {
+ (self.split_off_left(), self, FindReducer)
+ }
+
+ fn into_folder(self) -> Self::Folder {
+ FindFolder {
+ find_op: self.find_op,
+ found: self.found,
+ item: None,
+ }
+ }
+
+ fn full(&self) -> bool {
+ self.found.load(Ordering::Relaxed)
+ }
+}
+
+impl<'p, T, P: 'p> UnindexedConsumer<T> for FindConsumer<'p, P>
+where
+ T: Send,
+ P: Fn(&T) -> bool + Sync,
+{
+ fn split_off_left(&self) -> Self {
+ FindConsumer::new(self.find_op, self.found)
+ }
+
+ fn to_reducer(&self) -> Self::Reducer {
+ FindReducer
+ }
+}
+
+struct FindFolder<'p, T, P> {
+ find_op: &'p P,
+ found: &'p AtomicBool,
+ item: Option<T>,
+}
+
+impl<'p, T, P> Folder<T> for FindFolder<'p, T, P>
+where
+ P: Fn(&T) -> bool + 'p,
+{
+ type Result = Option<T>;
+
+ fn consume(mut self, item: T) -> Self {
+ if (self.find_op)(&item) {
+ self.found.store(true, Ordering::Relaxed);
+ self.item = Some(item);
+ }
+ self
+ }
+
+ fn consume_iter<I>(mut self, iter: I) -> Self
+ where
+ I: IntoIterator<Item = T>,
+ {
+ fn not_full<T>(found: &AtomicBool) -> impl Fn(&T) -> bool + '_ {
+ move |_| !found.load(Ordering::Relaxed)
+ }
+
+ self.item = iter
+ .into_iter()
+ // stop iterating if another thread has found something
+ .take_while(not_full(self.found))
+ .find(self.find_op);
+ if self.item.is_some() {
+ self.found.store(true, Ordering::Relaxed)
+ }
+ self
+ }
+
+ fn complete(self) -> Self::Result {
+ self.item
+ }
+
+ fn full(&self) -> bool {
+ self.found.load(Ordering::Relaxed)
+ }
+}
+
+struct FindReducer;
+
+impl<T> Reducer<Option<T>> for FindReducer {
+ fn reduce(self, left: Option<T>, right: Option<T>) -> Option<T> {
+ left.or(right)
+ }
+}