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-rw-r--r--vendor/rayon/src/iter/try_reduce.rs132
1 files changed, 132 insertions, 0 deletions
diff --git a/vendor/rayon/src/iter/try_reduce.rs b/vendor/rayon/src/iter/try_reduce.rs
new file mode 100644
index 000000000..7bf6cc4a5
--- /dev/null
+++ b/vendor/rayon/src/iter/try_reduce.rs
@@ -0,0 +1,132 @@
+use super::plumbing::*;
+use super::ParallelIterator;
+use super::Try;
+
+use super::private::ControlFlow::{self, Break, Continue};
+
+use std::sync::atomic::{AtomicBool, Ordering};
+
+pub(super) fn try_reduce<PI, R, ID, T>(pi: PI, identity: ID, reduce_op: R) -> T
+where
+ PI: ParallelIterator<Item = T>,
+ R: Fn(T::Output, T::Output) -> T + Sync,
+ ID: Fn() -> T::Output + Sync,
+ T: Try + Send,
+{
+ let full = AtomicBool::new(false);
+ let consumer = TryReduceConsumer {
+ identity: &identity,
+ reduce_op: &reduce_op,
+ full: &full,
+ };
+ pi.drive_unindexed(consumer)
+}
+
+struct TryReduceConsumer<'r, R, ID> {
+ identity: &'r ID,
+ reduce_op: &'r R,
+ full: &'r AtomicBool,
+}
+
+impl<'r, R, ID> Copy for TryReduceConsumer<'r, R, ID> {}
+
+impl<'r, R, ID> Clone for TryReduceConsumer<'r, R, ID> {
+ fn clone(&self) -> Self {
+ *self
+ }
+}
+
+impl<'r, R, ID, T> Consumer<T> for TryReduceConsumer<'r, R, ID>
+where
+ R: Fn(T::Output, T::Output) -> T + Sync,
+ ID: Fn() -> T::Output + Sync,
+ T: Try + Send,
+{
+ type Folder = TryReduceFolder<'r, R, T>;
+ type Reducer = Self;
+ type Result = T;
+
+ fn split_at(self, _index: usize) -> (Self, Self, Self) {
+ (self, self, self)
+ }
+
+ fn into_folder(self) -> Self::Folder {
+ TryReduceFolder {
+ reduce_op: self.reduce_op,
+ control: Continue((self.identity)()),
+ full: self.full,
+ }
+ }
+
+ fn full(&self) -> bool {
+ self.full.load(Ordering::Relaxed)
+ }
+}
+
+impl<'r, R, ID, T> UnindexedConsumer<T> for TryReduceConsumer<'r, R, ID>
+where
+ R: Fn(T::Output, T::Output) -> T + Sync,
+ ID: Fn() -> T::Output + Sync,
+ T: Try + Send,
+{
+ fn split_off_left(&self) -> Self {
+ *self
+ }
+
+ fn to_reducer(&self) -> Self::Reducer {
+ *self
+ }
+}
+
+impl<'r, R, ID, T> Reducer<T> for TryReduceConsumer<'r, R, ID>
+where
+ R: Fn(T::Output, T::Output) -> T + Sync,
+ T: Try,
+{
+ fn reduce(self, left: T, right: T) -> T {
+ match (left.branch(), right.branch()) {
+ (Continue(left), Continue(right)) => (self.reduce_op)(left, right),
+ (Break(r), _) | (_, Break(r)) => T::from_residual(r),
+ }
+ }
+}
+
+struct TryReduceFolder<'r, R, T: Try> {
+ reduce_op: &'r R,
+ control: ControlFlow<T::Residual, T::Output>,
+ full: &'r AtomicBool,
+}
+
+impl<'r, R, T> Folder<T> for TryReduceFolder<'r, R, T>
+where
+ R: Fn(T::Output, T::Output) -> T,
+ T: Try,
+{
+ type Result = T;
+
+ fn consume(mut self, item: T) -> Self {
+ let reduce_op = self.reduce_op;
+ self.control = match (self.control, item.branch()) {
+ (Continue(left), Continue(right)) => reduce_op(left, right).branch(),
+ (control @ Break(_), _) | (_, control @ Break(_)) => control,
+ };
+ if let Break(_) = self.control {
+ self.full.store(true, Ordering::Relaxed);
+ }
+ self
+ }
+
+ fn complete(self) -> T {
+ match self.control {
+ Continue(c) => T::from_output(c),
+ Break(r) => T::from_residual(r),
+ }
+ }
+
+ fn full(&self) -> bool {
+ match self.control {
+ Break(_) => true,
+ _ => self.full.load(Ordering::Relaxed),
+ }
+ }
+}