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-rw-r--r--vendor/rayon/src/iter/skip_any.rs144
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diff --git a/vendor/rayon/src/iter/skip_any.rs b/vendor/rayon/src/iter/skip_any.rs
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+use super::plumbing::*;
+use super::*;
+use std::sync::atomic::{AtomicUsize, Ordering};
+
+/// `SkipAny` is an iterator that skips over `n` elements from anywhere in `I`.
+/// This struct is created by the [`skip_any()`] method on [`ParallelIterator`]
+///
+/// [`skip_any()`]: trait.ParallelIterator.html#method.skip_any
+/// [`ParallelIterator`]: trait.ParallelIterator.html
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
+#[derive(Clone, Debug)]
+pub struct SkipAny<I: ParallelIterator> {
+ base: I,
+ count: usize,
+}
+
+impl<I> SkipAny<I>
+where
+ I: ParallelIterator,
+{
+ /// Creates a new `SkipAny` iterator.
+ pub(super) fn new(base: I, count: usize) -> Self {
+ SkipAny { base, count }
+ }
+}
+
+impl<I> ParallelIterator for SkipAny<I>
+where
+ I: ParallelIterator,
+{
+ type Item = I::Item;
+
+ fn drive_unindexed<C>(self, consumer: C) -> C::Result
+ where
+ C: UnindexedConsumer<Self::Item>,
+ {
+ let consumer1 = SkipAnyConsumer {
+ base: consumer,
+ count: &AtomicUsize::new(self.count),
+ };
+ self.base.drive_unindexed(consumer1)
+ }
+}
+
+/// ////////////////////////////////////////////////////////////////////////
+/// Consumer implementation
+
+struct SkipAnyConsumer<'f, C> {
+ base: C,
+ count: &'f AtomicUsize,
+}
+
+impl<'f, T, C> Consumer<T> for SkipAnyConsumer<'f, C>
+where
+ C: Consumer<T>,
+ T: Send,
+{
+ type Folder = SkipAnyFolder<'f, C::Folder>;
+ type Reducer = C::Reducer;
+ type Result = C::Result;
+
+ fn split_at(self, index: usize) -> (Self, Self, Self::Reducer) {
+ let (left, right, reducer) = self.base.split_at(index);
+ (
+ SkipAnyConsumer { base: left, ..self },
+ SkipAnyConsumer {
+ base: right,
+ ..self
+ },
+ reducer,
+ )
+ }
+
+ fn into_folder(self) -> Self::Folder {
+ SkipAnyFolder {
+ base: self.base.into_folder(),
+ count: self.count,
+ }
+ }
+
+ fn full(&self) -> bool {
+ self.base.full()
+ }
+}
+
+impl<'f, T, C> UnindexedConsumer<T> for SkipAnyConsumer<'f, C>
+where
+ C: UnindexedConsumer<T>,
+ T: Send,
+{
+ fn split_off_left(&self) -> Self {
+ SkipAnyConsumer {
+ base: self.base.split_off_left(),
+ ..*self
+ }
+ }
+
+ fn to_reducer(&self) -> Self::Reducer {
+ self.base.to_reducer()
+ }
+}
+
+struct SkipAnyFolder<'f, C> {
+ base: C,
+ count: &'f AtomicUsize,
+}
+
+fn checked_decrement(u: &AtomicUsize) -> bool {
+ u.fetch_update(Ordering::Relaxed, Ordering::Relaxed, |u| u.checked_sub(1))
+ .is_ok()
+}
+
+impl<'f, T, C> Folder<T> for SkipAnyFolder<'f, C>
+where
+ C: Folder<T>,
+{
+ type Result = C::Result;
+
+ fn consume(mut self, item: T) -> Self {
+ if !checked_decrement(self.count) {
+ self.base = self.base.consume(item);
+ }
+ self
+ }
+
+ fn consume_iter<I>(mut self, iter: I) -> Self
+ where
+ I: IntoIterator<Item = T>,
+ {
+ self.base = self.base.consume_iter(
+ iter.into_iter()
+ .skip_while(move |_| checked_decrement(self.count)),
+ );
+ self
+ }
+
+ fn complete(self) -> C::Result {
+ self.base.complete()
+ }
+
+ fn full(&self) -> bool {
+ self.base.full()
+ }
+}