diff options
Diffstat (limited to 'vendor/rayon/src/iter/update.rs')
-rw-r--r-- | vendor/rayon/src/iter/update.rs | 327 |
1 files changed, 327 insertions, 0 deletions
diff --git a/vendor/rayon/src/iter/update.rs b/vendor/rayon/src/iter/update.rs new file mode 100644 index 0000000..c693ac8 --- /dev/null +++ b/vendor/rayon/src/iter/update.rs @@ -0,0 +1,327 @@ +use super::plumbing::*; +use super::*; + +use std::fmt::{self, Debug}; + +/// `Update` is an iterator that mutates the elements of an +/// underlying iterator before they are yielded. +/// +/// This struct is created by the [`update()`] method on [`ParallelIterator`] +/// +/// [`update()`]: trait.ParallelIterator.html#method.update +/// [`ParallelIterator`]: trait.ParallelIterator.html +#[must_use = "iterator adaptors are lazy and do nothing unless consumed"] +#[derive(Clone)] +pub struct Update<I: ParallelIterator, F> { + base: I, + update_op: F, +} + +impl<I: ParallelIterator + Debug, F> Debug for Update<I, F> { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.debug_struct("Update").field("base", &self.base).finish() + } +} + +impl<I, F> Update<I, F> +where + I: ParallelIterator, +{ + /// Creates a new `Update` iterator. + pub(super) fn new(base: I, update_op: F) -> Self { + Update { base, update_op } + } +} + +impl<I, F> ParallelIterator for Update<I, F> +where + I: ParallelIterator, + F: Fn(&mut I::Item) + Send + Sync, +{ + type Item = I::Item; + + fn drive_unindexed<C>(self, consumer: C) -> C::Result + where + C: UnindexedConsumer<Self::Item>, + { + let consumer1 = UpdateConsumer::new(consumer, &self.update_op); + self.base.drive_unindexed(consumer1) + } + + fn opt_len(&self) -> Option<usize> { + self.base.opt_len() + } +} + +impl<I, F> IndexedParallelIterator for Update<I, F> +where + I: IndexedParallelIterator, + F: Fn(&mut I::Item) + Send + Sync, +{ + fn drive<C>(self, consumer: C) -> C::Result + where + C: Consumer<Self::Item>, + { + let consumer1 = UpdateConsumer::new(consumer, &self.update_op); + self.base.drive(consumer1) + } + + fn len(&self) -> usize { + self.base.len() + } + + fn with_producer<CB>(self, callback: CB) -> CB::Output + where + CB: ProducerCallback<Self::Item>, + { + return self.base.with_producer(Callback { + callback, + update_op: self.update_op, + }); + + struct Callback<CB, F> { + callback: CB, + update_op: F, + } + + impl<T, F, CB> ProducerCallback<T> for Callback<CB, F> + where + CB: ProducerCallback<T>, + F: Fn(&mut T) + Send + Sync, + { + type Output = CB::Output; + + fn callback<P>(self, base: P) -> CB::Output + where + P: Producer<Item = T>, + { + let producer = UpdateProducer { + base, + update_op: &self.update_op, + }; + self.callback.callback(producer) + } + } + } +} + +/// //////////////////////////////////////////////////////////////////////// + +struct UpdateProducer<'f, P, F> { + base: P, + update_op: &'f F, +} + +impl<'f, P, F> Producer for UpdateProducer<'f, P, F> +where + P: Producer, + F: Fn(&mut P::Item) + Send + Sync, +{ + type Item = P::Item; + type IntoIter = UpdateSeq<P::IntoIter, &'f F>; + + fn into_iter(self) -> Self::IntoIter { + UpdateSeq { + base: self.base.into_iter(), + update_op: self.update_op, + } + } + + fn min_len(&self) -> usize { + self.base.min_len() + } + fn max_len(&self) -> usize { + self.base.max_len() + } + + fn split_at(self, index: usize) -> (Self, Self) { + let (left, right) = self.base.split_at(index); + ( + UpdateProducer { + base: left, + update_op: self.update_op, + }, + UpdateProducer { + base: right, + update_op: self.update_op, + }, + ) + } + + fn fold_with<G>(self, folder: G) -> G + where + G: Folder<Self::Item>, + { + let folder1 = UpdateFolder { + base: folder, + update_op: self.update_op, + }; + self.base.fold_with(folder1).base + } +} + +/// //////////////////////////////////////////////////////////////////////// +/// Consumer implementation + +struct UpdateConsumer<'f, C, F> { + base: C, + update_op: &'f F, +} + +impl<'f, C, F> UpdateConsumer<'f, C, F> { + fn new(base: C, update_op: &'f F) -> Self { + UpdateConsumer { base, update_op } + } +} + +impl<'f, T, C, F> Consumer<T> for UpdateConsumer<'f, C, F> +where + C: Consumer<T>, + F: Fn(&mut T) + Send + Sync, +{ + type Folder = UpdateFolder<'f, C::Folder, F>; + 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); + ( + UpdateConsumer::new(left, self.update_op), + UpdateConsumer::new(right, self.update_op), + reducer, + ) + } + + fn into_folder(self) -> Self::Folder { + UpdateFolder { + base: self.base.into_folder(), + update_op: self.update_op, + } + } + + fn full(&self) -> bool { + self.base.full() + } +} + +impl<'f, T, C, F> UnindexedConsumer<T> for UpdateConsumer<'f, C, F> +where + C: UnindexedConsumer<T>, + F: Fn(&mut T) + Send + Sync, +{ + fn split_off_left(&self) -> Self { + UpdateConsumer::new(self.base.split_off_left(), self.update_op) + } + + fn to_reducer(&self) -> Self::Reducer { + self.base.to_reducer() + } +} + +struct UpdateFolder<'f, C, F> { + base: C, + update_op: &'f F, +} + +fn apply<T>(update_op: impl Fn(&mut T)) -> impl Fn(T) -> T { + move |mut item| { + update_op(&mut item); + item + } +} + +impl<'f, T, C, F> Folder<T> for UpdateFolder<'f, C, F> +where + C: Folder<T>, + F: Fn(&mut T), +{ + type Result = C::Result; + + fn consume(self, mut item: T) -> Self { + (self.update_op)(&mut item); + + UpdateFolder { + base: self.base.consume(item), + update_op: self.update_op, + } + } + + fn consume_iter<I>(mut self, iter: I) -> Self + where + I: IntoIterator<Item = T>, + { + let update_op = self.update_op; + self.base = self + .base + .consume_iter(iter.into_iter().map(apply(update_op))); + self + } + + fn complete(self) -> C::Result { + self.base.complete() + } + + fn full(&self) -> bool { + self.base.full() + } +} + +/// Standard Update adaptor, based on `itertools::adaptors::Update` +#[must_use = "iterator adaptors are lazy and do nothing unless consumed"] +#[derive(Debug, Clone)] +struct UpdateSeq<I, F> { + base: I, + update_op: F, +} + +impl<I, F> Iterator for UpdateSeq<I, F> +where + I: Iterator, + F: Fn(&mut I::Item), +{ + type Item = I::Item; + + fn next(&mut self) -> Option<Self::Item> { + let mut v = self.base.next()?; + (self.update_op)(&mut v); + Some(v) + } + + fn size_hint(&self) -> (usize, Option<usize>) { + self.base.size_hint() + } + + fn fold<Acc, G>(self, init: Acc, g: G) -> Acc + where + G: FnMut(Acc, Self::Item) -> Acc, + { + self.base.map(apply(self.update_op)).fold(init, g) + } + + // if possible, re-use inner iterator specializations in collect + fn collect<C>(self) -> C + where + C: ::std::iter::FromIterator<Self::Item>, + { + self.base.map(apply(self.update_op)).collect() + } +} + +impl<I, F> ExactSizeIterator for UpdateSeq<I, F> +where + I: ExactSizeIterator, + F: Fn(&mut I::Item), +{ +} + +impl<I, F> DoubleEndedIterator for UpdateSeq<I, F> +where + I: DoubleEndedIterator, + F: Fn(&mut I::Item), +{ + fn next_back(&mut self) -> Option<Self::Item> { + let mut v = self.base.next_back()?; + (self.update_op)(&mut v); + Some(v) + } +} |