forked from mirror/async-std
45 lines
1.2 KiB
Rust
45 lines
1.2 KiB
Rust
use std::marker::PhantomData;
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use std::pin::Pin;
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use crate::future::Future;
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use crate::stream::Stream;
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use crate::task::{Context, Poll};
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#[doc(hidden)]
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#[allow(missing_debug_implementations)]
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pub struct AllFuture<'a, S, F, T> {
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pub(crate) stream: &'a mut S,
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pub(crate) f: F,
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pub(crate) result: bool,
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pub(crate) _marker: PhantomData<T>,
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}
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impl<S: Unpin, F, T> Unpin for AllFuture<'_, S, F, T> {}
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impl<S, F> Future for AllFuture<'_, S, F, S::Item>
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where
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S: Stream + Unpin + Sized,
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F: FnMut(S::Item) -> bool,
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{
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type Output = bool;
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fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
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let next = futures_core::ready!(Pin::new(&mut *self.stream).poll_next(cx));
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match next {
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Some(v) => {
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let result = (&mut self.f)(v);
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self.result = result;
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if result {
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// don't forget to wake this task again to pull the next item from stream
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cx.waker().wake_by_ref();
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Poll::Pending
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} else {
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Poll::Ready(false)
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}
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}
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None => Poll::Ready(self.result),
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}
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}
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}
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