Function poll_once

pub fn poll_once<T, F>(f: F) -> PollOnce<F> 
where
    F: Future<Output = T>,

Polls a future just once and returns an Option with the result.

Examples

use futures_lite::future;

assert_eq!(future::poll_once(future::pending::<()>()).await, None);
assert_eq!(future::poll_once(future::ready(42)).await, Some(42));