26 lines
640 B
Rust
26 lines
640 B
Rust
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use futures::{Future, FutureExt, Stream, StreamExt, future::OptionFuture};
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use super::super::IterStream;
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pub trait OptionStream<T> {
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fn stream(self) -> impl Stream<Item = T> + Send;
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}
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impl<T, O, S, Fut> OptionStream<T> for OptionFuture<Fut>
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where
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Fut: Future<Output = (O, S)> + Send,
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S: Stream<Item = T> + Send,
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O: IntoIterator<Item = T> + Send,
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<O as IntoIterator>::IntoIter: Send,
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T: Send,
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{
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#[inline]
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fn stream(self) -> impl Stream<Item = T> + Send {
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self.map(|opt| opt.map(|(curr, next)| curr.into_iter().stream().chain(next)))
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.map(Option::into_iter)
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.map(IterStream::stream)
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.flatten_stream()
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.flatten()
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}
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}
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