Method poll

crates/guest-rust/src/rt/async_support.rs:617–625

(mut self: Pin<&mut Self>, context: &mut Context<'_>)

        type Output = ();

        fn poll(mut self: Pin<&mut Self>, context: &mut Context<'_>) -> Poll<()> {
            if self.yielded {
                Poll::Ready(())
            } else {
                self.yielded = true;
                context.waker().wake_by_ref();
                Poll::Pending
            }
        }
    }

    Yield::default().await;