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-rw-r--r--src/stream/fold.rs57
1 files changed, 0 insertions, 57 deletions
diff --git a/src/stream/fold.rs b/src/stream/fold.rs
deleted file mode 100644
index 5cf2bfa..0000000
--- a/src/stream/fold.rs
+++ /dev/null
@@ -1,57 +0,0 @@
-use crate::stream::Stream;
-
-use core::future::Future;
-use core::marker::PhantomPinned;
-use core::pin::Pin;
-use core::task::{Context, Poll};
-use pin_project_lite::pin_project;
-
-pin_project! {
- /// Future returned by the [`fold`](super::StreamExt::fold) method.
- #[derive(Debug)]
- #[must_use = "futures do nothing unless you `.await` or poll them"]
- pub struct FoldFuture<St, B, F> {
- #[pin]
- stream: St,
- acc: Option<B>,
- f: F,
- // Make this future `!Unpin` for compatibility with async trait methods.
- #[pin]
- _pin: PhantomPinned,
- }
-}
-
-impl<St, B, F> FoldFuture<St, B, F> {
- pub(super) fn new(stream: St, init: B, f: F) -> Self {
- Self {
- stream,
- acc: Some(init),
- f,
- _pin: PhantomPinned,
- }
- }
-}
-
-impl<St, B, F> Future for FoldFuture<St, B, F>
-where
- St: Stream,
- F: FnMut(B, St::Item) -> B,
-{
- type Output = B;
-
- fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
- let mut me = self.project();
- loop {
- let next = ready!(me.stream.as_mut().poll_next(cx));
-
- match next {
- Some(v) => {
- let old = me.acc.take().unwrap();
- let new = (me.f)(old, v);
- *me.acc = Some(new);
- }
- None => return Poll::Ready(me.acc.take().unwrap()),
- }
- }
- }
-}