Function async_std::stream::repeat_with
source · pub fn repeat_with<T, F>(repeater: F) -> RepeatWith<F>where
F: FnMut() -> T,
Expand description
Creates a new stream that repeats elements of type A
endlessly by applying the provided closure.
Examples
Basic usage:
use async_std::prelude::*;
use async_std::stream;
let s = stream::repeat_with(|| 1);
pin_utils::pin_mut!(s);
assert_eq!(s.next().await, Some(1));
assert_eq!(s.next().await, Some(1));
assert_eq!(s.next().await, Some(1));
assert_eq!(s.next().await, Some(1));
Going finite:
use async_std::prelude::*;
use async_std::stream;
let mut n = 1;
let s = stream::repeat_with(|| {
let item = n;
n *= 2;
item
})
.take(4);
pin_utils::pin_mut!(s);
assert_eq!(s.next().await, Some(1));
assert_eq!(s.next().await, Some(2));
assert_eq!(s.next().await, Some(4));
assert_eq!(s.next().await, Some(8));
assert_eq!(s.next().await, None);