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-rw-r--r--vendor/rayon/src/iter/reduce.rs116
1 files changed, 116 insertions, 0 deletions
diff --git a/vendor/rayon/src/iter/reduce.rs b/vendor/rayon/src/iter/reduce.rs
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+++ b/vendor/rayon/src/iter/reduce.rs
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+use super::plumbing::*;
+use super::ParallelIterator;
+
+pub(super) fn reduce<PI, R, ID, T>(pi: PI, identity: ID, reduce_op: R) -> T
+where
+ PI: ParallelIterator<Item = T>,
+ R: Fn(T, T) -> T + Sync,
+ ID: Fn() -> T + Sync,
+ T: Send,
+{
+ let consumer = ReduceConsumer {
+ identity: &identity,
+ reduce_op: &reduce_op,
+ };
+ pi.drive_unindexed(consumer)
+}
+
+struct ReduceConsumer<'r, R, ID> {
+ identity: &'r ID,
+ reduce_op: &'r R,
+}
+
+impl<'r, R, ID> Copy for ReduceConsumer<'r, R, ID> {}
+
+impl<'r, R, ID> Clone for ReduceConsumer<'r, R, ID> {
+ fn clone(&self) -> Self {
+ *self
+ }
+}
+
+impl<'r, R, ID, T> Consumer<T> for ReduceConsumer<'r, R, ID>
+where
+ R: Fn(T, T) -> T + Sync,
+ ID: Fn() -> T + Sync,
+ T: Send,
+{
+ type Folder = ReduceFolder<'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 {
+ ReduceFolder {
+ reduce_op: self.reduce_op,
+ item: (self.identity)(),
+ }
+ }
+
+ fn full(&self) -> bool {
+ false
+ }
+}
+
+impl<'r, R, ID, T> UnindexedConsumer<T> for ReduceConsumer<'r, R, ID>
+where
+ R: Fn(T, T) -> T + Sync,
+ ID: Fn() -> T + Sync,
+ T: Send,
+{
+ fn split_off_left(&self) -> Self {
+ *self
+ }
+
+ fn to_reducer(&self) -> Self::Reducer {
+ *self
+ }
+}
+
+impl<'r, R, ID, T> Reducer<T> for ReduceConsumer<'r, R, ID>
+where
+ R: Fn(T, T) -> T + Sync,
+{
+ fn reduce(self, left: T, right: T) -> T {
+ (self.reduce_op)(left, right)
+ }
+}
+
+struct ReduceFolder<'r, R, T> {
+ reduce_op: &'r R,
+ item: T,
+}
+
+impl<'r, R, T> Folder<T> for ReduceFolder<'r, R, T>
+where
+ R: Fn(T, T) -> T,
+{
+ type Result = T;
+
+ fn consume(self, item: T) -> Self {
+ ReduceFolder {
+ reduce_op: self.reduce_op,
+ item: (self.reduce_op)(self.item, item),
+ }
+ }
+
+ fn consume_iter<I>(self, iter: I) -> Self
+ where
+ I: IntoIterator<Item = T>,
+ {
+ ReduceFolder {
+ reduce_op: self.reduce_op,
+ item: iter.into_iter().fold(self.item, self.reduce_op),
+ }
+ }
+
+ fn complete(self) -> T {
+ self.item
+ }
+
+ fn full(&self) -> bool {
+ false
+ }
+}