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Diffstat (limited to 'vendor/rayon/src/iter/flatten_iter.rs')
-rw-r--r-- | vendor/rayon/src/iter/flatten_iter.rs | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/vendor/rayon/src/iter/flatten_iter.rs b/vendor/rayon/src/iter/flatten_iter.rs new file mode 100644 index 0000000..3ce0a3c --- /dev/null +++ b/vendor/rayon/src/iter/flatten_iter.rs @@ -0,0 +1,132 @@ +use super::plumbing::*; +use super::*; + +/// `FlattenIter` turns each element to a serial iterator, then flattens these iterators +/// together. This struct is created by the [`flatten_iter()`] method on [`ParallelIterator`]. +/// +/// [`flatten_iter()`]: trait.ParallelIterator.html#method.flatten_iter +/// [`ParallelIterator`]: trait.ParallelIterator.html +#[must_use = "iterator adaptors are lazy and do nothing unless consumed"] +#[derive(Debug, Clone)] +pub struct FlattenIter<I: ParallelIterator> { + base: I, +} + +impl<I> FlattenIter<I> +where + I: ParallelIterator, + I::Item: IntoIterator, + <I::Item as IntoIterator>::Item: Send, +{ + /// Creates a new `FlattenIter` iterator. + pub(super) fn new(base: I) -> Self { + FlattenIter { base } + } +} + +impl<I> ParallelIterator for FlattenIter<I> +where + I: ParallelIterator, + I::Item: IntoIterator, + <I::Item as IntoIterator>::Item: Send, +{ + type Item = <I::Item as IntoIterator>::Item; + + fn drive_unindexed<C>(self, consumer: C) -> C::Result + where + C: UnindexedConsumer<Self::Item>, + { + let consumer = FlattenIterConsumer::new(consumer); + self.base.drive_unindexed(consumer) + } +} + +/// //////////////////////////////////////////////////////////////////////// +/// Consumer implementation + +struct FlattenIterConsumer<C> { + base: C, +} + +impl<C> FlattenIterConsumer<C> { + fn new(base: C) -> Self { + FlattenIterConsumer { base } + } +} + +impl<T, C> Consumer<T> for FlattenIterConsumer<C> +where + C: UnindexedConsumer<T::Item>, + T: IntoIterator, +{ + type Folder = FlattenIterFolder<C::Folder>; + 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); + ( + FlattenIterConsumer::new(left), + FlattenIterConsumer::new(right), + reducer, + ) + } + + fn into_folder(self) -> Self::Folder { + FlattenIterFolder { + base: self.base.into_folder(), + } + } + + fn full(&self) -> bool { + self.base.full() + } +} + +impl<T, C> UnindexedConsumer<T> for FlattenIterConsumer<C> +where + C: UnindexedConsumer<T::Item>, + T: IntoIterator, +{ + fn split_off_left(&self) -> Self { + FlattenIterConsumer::new(self.base.split_off_left()) + } + + fn to_reducer(&self) -> Self::Reducer { + self.base.to_reducer() + } +} + +struct FlattenIterFolder<C> { + base: C, +} + +impl<T, C> Folder<T> for FlattenIterFolder<C> +where + C: Folder<T::Item>, + T: IntoIterator, +{ + type Result = C::Result; + + fn consume(self, item: T) -> Self { + let base = self.base.consume_iter(item); + FlattenIterFolder { base } + } + + fn consume_iter<I>(self, iter: I) -> Self + where + I: IntoIterator<Item = T>, + { + let iter = iter.into_iter().flatten(); + let base = self.base.consume_iter(iter); + FlattenIterFolder { base } + } + + fn complete(self) -> Self::Result { + self.base.complete() + } + + fn full(&self) -> bool { + self.base.full() + } +} |