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