From 26a029d407be480d791972afb5975cf62c9360a6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Fri, 19 Apr 2024 02:47:55 +0200 Subject: Adding upstream version 124.0.1. Signed-off-by: Daniel Baumann --- third_party/rust/rayon/src/iter/take.rs | 86 +++++++++++++++++++++++++++++++++ 1 file changed, 86 insertions(+) create mode 100644 third_party/rust/rayon/src/iter/take.rs (limited to 'third_party/rust/rayon/src/iter/take.rs') diff --git a/third_party/rust/rayon/src/iter/take.rs b/third_party/rust/rayon/src/iter/take.rs new file mode 100644 index 0000000000..52d15d805c --- /dev/null +++ b/third_party/rust/rayon/src/iter/take.rs @@ -0,0 +1,86 @@ +use super::plumbing::*; +use super::*; +use std::cmp::min; + +/// `Take` is an iterator that iterates over the first `n` elements. +/// This struct is created by the [`take()`] method on [`IndexedParallelIterator`] +/// +/// [`take()`]: trait.IndexedParallelIterator.html#method.take +/// [`IndexedParallelIterator`]: trait.IndexedParallelIterator.html +#[must_use = "iterator adaptors are lazy and do nothing unless consumed"] +#[derive(Debug, Clone)] +pub struct Take { + base: I, + n: usize, +} + +impl Take +where + I: IndexedParallelIterator, +{ + /// Creates a new `Take` iterator. + pub(super) fn new(base: I, n: usize) -> Self { + let n = min(base.len(), n); + Take { base, n } + } +} + +impl ParallelIterator for Take +where + I: IndexedParallelIterator, +{ + type Item = I::Item; + + fn drive_unindexed(self, consumer: C) -> C::Result + where + C: UnindexedConsumer, + { + bridge(self, consumer) + } + + fn opt_len(&self) -> Option { + Some(self.len()) + } +} + +impl IndexedParallelIterator for Take +where + I: IndexedParallelIterator, +{ + fn len(&self) -> usize { + self.n + } + + fn drive>(self, consumer: C) -> C::Result { + bridge(self, consumer) + } + + fn with_producer(self, callback: CB) -> CB::Output + where + CB: ProducerCallback, + { + return self.base.with_producer(Callback { + callback, + n: self.n, + }); + + struct Callback { + callback: CB, + n: usize, + } + + impl ProducerCallback for Callback + where + CB: ProducerCallback, + { + type Output = CB::Output; + fn callback

(self, base: P) -> CB::Output + where + P: Producer, + { + let (producer, _) = base.split_at(self.n); + self.callback.callback(producer) + } + } + } +} -- cgit v1.2.3