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-rw-r--r--vendor/rayon/src/iter/try_reduce_with.rs132
1 files changed, 132 insertions, 0 deletions
diff --git a/vendor/rayon/src/iter/try_reduce_with.rs b/vendor/rayon/src/iter/try_reduce_with.rs
new file mode 100644
index 0000000..cd7c83e
--- /dev/null
+++ b/vendor/rayon/src/iter/try_reduce_with.rs
@@ -0,0 +1,132 @@
+use super::plumbing::*;
+use super::ParallelIterator;
+use super::Try;
+
+use std::ops::ControlFlow::{self, Break, Continue};
+use std::sync::atomic::{AtomicBool, Ordering};
+
+pub(super) fn try_reduce_with<PI, R, T>(pi: PI, reduce_op: R) -> Option<T>
+where
+ PI: ParallelIterator<Item = T>,
+ R: Fn(T::Output, T::Output) -> T + Sync,
+ T: Try + Send,
+{
+ let full = AtomicBool::new(false);
+ let consumer = TryReduceWithConsumer {
+ reduce_op: &reduce_op,
+ full: &full,
+ };
+ pi.drive_unindexed(consumer)
+}
+
+struct TryReduceWithConsumer<'r, R> {
+ reduce_op: &'r R,
+ full: &'r AtomicBool,
+}
+
+impl<'r, R> Copy for TryReduceWithConsumer<'r, R> {}
+
+impl<'r, R> Clone for TryReduceWithConsumer<'r, R> {
+ fn clone(&self) -> Self {
+ *self
+ }
+}
+
+impl<'r, R, T> Consumer<T> for TryReduceWithConsumer<'r, R>
+where
+ R: Fn(T::Output, T::Output) -> T + Sync,
+ T: Try + Send,
+{
+ type Folder = TryReduceWithFolder<'r, R, T>;
+ type Reducer = Self;
+ type Result = Option<T>;
+
+ fn split_at(self, _index: usize) -> (Self, Self, Self) {
+ (self, self, self)
+ }
+
+ fn into_folder(self) -> Self::Folder {
+ TryReduceWithFolder {
+ reduce_op: self.reduce_op,
+ opt_control: None,
+ full: self.full,
+ }
+ }
+
+ fn full(&self) -> bool {
+ self.full.load(Ordering::Relaxed)
+ }
+}
+
+impl<'r, R, T> UnindexedConsumer<T> for TryReduceWithConsumer<'r, R>
+where
+ R: Fn(T::Output, T::Output) -> T + Sync,
+ T: Try + Send,
+{
+ fn split_off_left(&self) -> Self {
+ *self
+ }
+
+ fn to_reducer(&self) -> Self::Reducer {
+ *self
+ }
+}
+
+impl<'r, R, T> Reducer<Option<T>> for TryReduceWithConsumer<'r, R>
+where
+ R: Fn(T::Output, T::Output) -> T + Sync,
+ T: Try,
+{
+ fn reduce(self, left: Option<T>, right: Option<T>) -> Option<T> {
+ let reduce_op = self.reduce_op;
+ match (left, right) {
+ (Some(left), Some(right)) => match (left.branch(), right.branch()) {
+ (Continue(left), Continue(right)) => Some(reduce_op(left, right)),
+ (Break(r), _) | (_, Break(r)) => Some(T::from_residual(r)),
+ },
+ (None, x) | (x, None) => x,
+ }
+ }
+}
+
+struct TryReduceWithFolder<'r, R, T: Try> {
+ reduce_op: &'r R,
+ opt_control: Option<ControlFlow<T::Residual, T::Output>>,
+ full: &'r AtomicBool,
+}
+
+impl<'r, R, T> Folder<T> for TryReduceWithFolder<'r, R, T>
+where
+ R: Fn(T::Output, T::Output) -> T,
+ T: Try,
+{
+ type Result = Option<T>;
+
+ fn consume(mut self, item: T) -> Self {
+ let reduce_op = self.reduce_op;
+ let control = match (self.opt_control, item.branch()) {
+ (Some(Continue(left)), Continue(right)) => reduce_op(left, right).branch(),
+ (Some(control @ Break(_)), _) | (_, control) => control,
+ };
+ if let Break(_) = control {
+ self.full.store(true, Ordering::Relaxed)
+ }
+ self.opt_control = Some(control);
+ self
+ }
+
+ fn complete(self) -> Option<T> {
+ match self.opt_control {
+ Some(Continue(c)) => Some(T::from_output(c)),
+ Some(Break(r)) => Some(T::from_residual(r)),
+ None => None,
+ }
+ }
+
+ fn full(&self) -> bool {
+ match self.opt_control {
+ Some(Break(_)) => true,
+ _ => self.full.load(Ordering::Relaxed),
+ }
+ }
+}