futures_lite::future
pub fn poll_once<T, F>(f: F) -> PollOnce<F>ⓘNotable traits for PollOnce<F>impl<T, F> Future for PollOnce<F> where F: Future<Output = T>, type Output = Option<T>; where F: Future<Output = T>,
impl<T, F> Future for PollOnce<F> where F: Future<Output = T>, type Output = Option<T>;
Polls a future just once and returns an Option with the result.
Option
use futures_lite::future; assert_eq!(future::poll_once(future::pending::<()>()).await, None); assert_eq!(future::poll_once(future::ready(42)).await, Some(42));