1 use core::marker::PhantomData; 2 use core::pin::Pin; 3 use futures_core::future::Future; 4 use futures_core::task::{Context, Poll}; 5 use futures_sink::Sink; 6 7 /// Future for the [`close`](super::SinkExt::close) method. 8 #[derive(Debug)] 9 #[must_use = "futures do nothing unless you `.await` or poll them"] 10 pub struct Close<'a, Si: ?Sized, Item> { 11 sink: &'a mut Si, 12 _phantom: PhantomData<fn(Item)>, 13 } 14 15 impl<Si: Unpin + ?Sized, Item> Unpin for Close<'_, Si, Item> {} 16 17 /// A future that completes when the sink has finished closing. 18 /// 19 /// The sink itself is returned after closing is complete. 20 impl<'a, Si: Sink<Item> + Unpin + ?Sized, Item> Close<'a, Si, Item> { new(sink: &'a mut Si) -> Self21 pub(super) fn new(sink: &'a mut Si) -> Self { 22 Self { sink, _phantom: PhantomData } 23 } 24 } 25 26 impl<Si: Sink<Item> + Unpin + ?Sized, Item> Future for Close<'_, Si, Item> { 27 type Output = Result<(), Si::Error>; 28 poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output>29 fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> { 30 Pin::new(&mut self.sink).poll_close(cx) 31 } 32 } 33