48 lines
820 B
Rust
48 lines
820 B
Rust
// check-pass
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// edition:2021
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#![allow(incomplete_features)]
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use std::future::Future;
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async fn yield_now() {}
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trait AsyncIterator {
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type Item;
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#[allow(async_fn_in_trait)]
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async fn next(&mut self) -> Option<Self::Item>;
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}
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struct YieldingRange {
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counter: u32,
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stop: u32,
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}
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impl AsyncIterator for YieldingRange {
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type Item = u32;
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async fn next(&mut self) -> Option<Self::Item> {
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if self.counter == self.stop {
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None
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} else {
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let c = self.counter;
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self.counter += 1;
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yield_now().await;
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Some(c)
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}
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}
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}
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async fn async_main() {
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let mut x = YieldingRange { counter: 0, stop: 10 };
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while let Some(v) = x.next().await {
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println!("Hi: {v}");
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}
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}
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fn main() {
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let _ = async_main();
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}
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