Alex Mikhalev
4c782addb7
All checks were successful
continuous-integration/drone/push Build is passing
38 lines
842 B
Rust
38 lines
842 B
Rust
use pin_project::pin_project;
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use std::{
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future::Future,
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ops::Deref,
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pin::Pin,
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task::{Context, Poll},
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};
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#[pin_project]
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#[derive(Debug, Clone)]
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#[must_use = "futures do nothing unless you `.await` or poll them"]
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pub struct OptionFuture<F>(#[pin] Option<F>);
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impl<F: Future> Future for OptionFuture<F> {
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type Output = Option<F::Output>;
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fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
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match self.project().0.as_pin_mut() {
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Some(x) => x.poll(cx).map(Some),
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None => Poll::Ready(None),
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}
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}
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}
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impl<F> Deref for OptionFuture<F> {
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type Target = Option<F>;
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fn deref(&self) -> &Self::Target {
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&self.0
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}
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}
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impl<T> From<Option<T>> for OptionFuture<T> {
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fn from(option: Option<T>) -> Self {
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OptionFuture(option)
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}
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}
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