diff options
Diffstat (limited to 'vendor/rayon/src/iter/product.rs')
-rw-r--r-- | vendor/rayon/src/iter/product.rs | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/vendor/rayon/src/iter/product.rs b/vendor/rayon/src/iter/product.rs new file mode 100644 index 0000000..e081be0 --- /dev/null +++ b/vendor/rayon/src/iter/product.rs @@ -0,0 +1,114 @@ +use super::plumbing::*; +use super::ParallelIterator; + +use std::iter::{self, Product}; +use std::marker::PhantomData; + +pub(super) fn product<PI, P>(pi: PI) -> P +where + PI: ParallelIterator, + P: Send + Product<PI::Item> + Product, +{ + pi.drive_unindexed(ProductConsumer::new()) +} + +fn mul<T: Product>(left: T, right: T) -> T { + [left, right].into_iter().product() +} + +struct ProductConsumer<P: Send> { + _marker: PhantomData<*const P>, +} + +unsafe impl<P: Send> Send for ProductConsumer<P> {} + +impl<P: Send> ProductConsumer<P> { + fn new() -> ProductConsumer<P> { + ProductConsumer { + _marker: PhantomData, + } + } +} + +impl<P, T> Consumer<T> for ProductConsumer<P> +where + P: Send + Product<T> + Product, +{ + type Folder = ProductFolder<P>; + type Reducer = Self; + type Result = P; + + fn split_at(self, _index: usize) -> (Self, Self, Self) { + ( + ProductConsumer::new(), + ProductConsumer::new(), + ProductConsumer::new(), + ) + } + + fn into_folder(self) -> Self::Folder { + ProductFolder { + product: iter::empty::<T>().product(), + } + } + + fn full(&self) -> bool { + false + } +} + +impl<P, T> UnindexedConsumer<T> for ProductConsumer<P> +where + P: Send + Product<T> + Product, +{ + fn split_off_left(&self) -> Self { + ProductConsumer::new() + } + + fn to_reducer(&self) -> Self::Reducer { + ProductConsumer::new() + } +} + +impl<P> Reducer<P> for ProductConsumer<P> +where + P: Send + Product, +{ + fn reduce(self, left: P, right: P) -> P { + mul(left, right) + } +} + +struct ProductFolder<P> { + product: P, +} + +impl<P, T> Folder<T> for ProductFolder<P> +where + P: Product<T> + Product, +{ + type Result = P; + + fn consume(self, item: T) -> Self { + ProductFolder { + product: mul(self.product, iter::once(item).product()), + } + } + + fn consume_iter<I>(self, iter: I) -> Self + where + I: IntoIterator<Item = T>, + { + ProductFolder { + product: mul(self.product, iter.into_iter().product()), + } + } + + fn complete(self) -> P { + self.product + } + + fn full(&self) -> bool { + false + } +} |