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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
commit698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch)
tree173a775858bd501c378080a10dca74132f05bc50 /vendor/rustc-rayon/src/iter/positions.rs
parentInitial commit. (diff)
downloadrustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz
rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'vendor/rustc-rayon/src/iter/positions.rs')
-rw-r--r--vendor/rustc-rayon/src/iter/positions.rs137
1 files changed, 137 insertions, 0 deletions
diff --git a/vendor/rustc-rayon/src/iter/positions.rs b/vendor/rustc-rayon/src/iter/positions.rs
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+++ b/vendor/rustc-rayon/src/iter/positions.rs
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+use super::plumbing::*;
+use super::*;
+
+use std::fmt::{self, Debug};
+
+/// `Positions` takes a predicate `predicate` and filters out elements that match,
+/// yielding their indices.
+///
+/// This struct is created by the [`positions()`] method on [`IndexedParallelIterator`]
+///
+/// [`positions()`]: trait.IndexedParallelIterator.html#method.positions
+/// [`IndexedParallelIterator`]: trait.IndexedParallelIterator.html
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
+#[derive(Clone)]
+pub struct Positions<I: IndexedParallelIterator, P> {
+ base: I,
+ predicate: P,
+}
+
+impl<I: IndexedParallelIterator + Debug, P> Debug for Positions<I, P> {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ f.debug_struct("Positions")
+ .field("base", &self.base)
+ .finish()
+ }
+}
+
+impl<I, P> Positions<I, P>
+where
+ I: IndexedParallelIterator,
+{
+ /// Create a new `Positions` iterator.
+ pub(super) fn new(base: I, predicate: P) -> Self {
+ Positions { base, predicate }
+ }
+}
+
+impl<I, P> ParallelIterator for Positions<I, P>
+where
+ I: IndexedParallelIterator,
+ P: Fn(I::Item) -> bool + Sync + Send,
+{
+ type Item = usize;
+
+ fn drive_unindexed<C>(self, consumer: C) -> C::Result
+ where
+ C: UnindexedConsumer<Self::Item>,
+ {
+ let consumer1 = PositionsConsumer::new(consumer, &self.predicate, 0);
+ self.base.drive(consumer1)
+ }
+}
+
+/// ////////////////////////////////////////////////////////////////////////
+/// Consumer implementation
+
+struct PositionsConsumer<'p, C, P> {
+ base: C,
+ predicate: &'p P,
+ offset: usize,
+}
+
+impl<'p, C, P> PositionsConsumer<'p, C, P> {
+ fn new(base: C, predicate: &'p P, offset: usize) -> Self {
+ PositionsConsumer {
+ base,
+ predicate,
+ offset,
+ }
+ }
+}
+
+impl<'p, T, C, P> Consumer<T> for PositionsConsumer<'p, C, P>
+where
+ C: Consumer<usize>,
+ P: Fn(T) -> bool + Sync,
+{
+ type Folder = PositionsFolder<'p, C::Folder, P>;
+ type Reducer = C::Reducer;
+ type Result = C::Result;
+
+ fn split_at(self, index: usize) -> (Self, Self, C::Reducer) {
+ let (left, right, reducer) = self.base.split_at(index);
+ (
+ PositionsConsumer::new(left, self.predicate, self.offset),
+ PositionsConsumer::new(right, self.predicate, self.offset + index),
+ reducer,
+ )
+ }
+
+ fn into_folder(self) -> Self::Folder {
+ PositionsFolder {
+ base: self.base.into_folder(),
+ predicate: self.predicate,
+ offset: self.offset,
+ }
+ }
+
+ fn full(&self) -> bool {
+ self.base.full()
+ }
+}
+
+struct PositionsFolder<'p, F, P> {
+ base: F,
+ predicate: &'p P,
+ offset: usize,
+}
+
+impl<F, P, T> Folder<T> for PositionsFolder<'_, F, P>
+where
+ F: Folder<usize>,
+ P: Fn(T) -> bool,
+{
+ type Result = F::Result;
+
+ fn consume(mut self, item: T) -> Self {
+ let index = self.offset;
+ self.offset += 1;
+ if (self.predicate)(item) {
+ self.base = self.base.consume(index);
+ }
+ self
+ }
+
+ // This cannot easily specialize `consume_iter` to be better than
+ // the default, because that requires checking `self.base.full()`
+ // during a call to `self.base.consume_iter()`. (#632)
+
+ fn complete(self) -> Self::Result {
+ self.base.complete()
+ }
+
+ fn full(&self) -> bool {
+ self.base.full()
+ }
+}