Trait rayon::iter::ParallelDrainFull

source ·

pub trait ParallelDrainFull {
    type Iter: ParallelIterator<Item = Self::Item>;
    type Item: Send;

    // Required method
    fn par_drain(self) -> Self::Iter;
}

Expand description

ParallelDrainFull creates a parallel iterator that moves all items from a collection while retaining the original capacity.

Types which are indexable typically implement ParallelDrainRange instead, where you can drain fully with par_drain(..).

Required Associated Types§

source

type Iter: ParallelIterator<Item = Self::Item>

The draining parallel iterator type that will be created.

source

type Item: Send

The type of item that the parallel iterator will produce. This is usually the same as IntoParallelIterator::Item.

Required Methods§

source

fn par_drain(self) -> Self::Iter

Returns a draining parallel iterator over an entire collection.

When the iterator is dropped, all items are removed, even if the iterator was not fully consumed. If the iterator is leaked, for example using std::mem::forget, it is unspecified how many items are removed.

Examples

use rayon::prelude::*;
use std::collections::{BinaryHeap, HashSet};

let squares: HashSet<i32> = (0..10).map(|x| x * x).collect();

let mut heap: BinaryHeap<_> = squares.iter().copied().collect();
assert_eq!(
    // heaps are drained in arbitrary order
    heap.par_drain()
        .inspect(|x| assert!(squares.contains(x)))
        .count(),
    squares.len(),
);
assert!(heap.is_empty());
assert!(heap.capacity() >= squares.len());