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pub async fn extend<'a, C, T, S>(collection: &mut C, stream: S) where
    C: Extend<T>,
    S: IntoStream<Item = T> + 'a,
    <S as IntoStream>::IntoStream: Send
Available on unstable only.
Expand description

Extends a collection with the contents of a stream.

Streams produce a series of values asynchronously, and collections can also be thought of as a series of values. The Extend trait bridges this gap, allowing you to extend a collection asynchronously by including the contents of that stream. When extending a collection with an already existing key, that entry is updated or, in the case of collections that permit multiple entries with equal keys, that entry is inserted.

Examples

use async_std::prelude::*;
use async_std::stream;

let mut v: Vec<usize> = vec![1, 2];
let s = stream::repeat(3usize).take(3);
stream::extend(&mut v, s).await;

assert_eq!(v, vec![1, 2, 3, 3, 3]);