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// run-pass
// revisions: default nomiropt
//[nomiropt]compile-flags: -Z mir-opt-level=0
#![feature(generators, generator_trait)]
use std::marker::Unpin;
use std::ops::{GeneratorState, Generator};
use std::pin::Pin;
fn finish<T>(mut amt: usize, mut t: T) -> T::Return
where T: Generator<(), Yield = ()> + Unpin,
{
loop {
match Pin::new(&mut t).resume(()) {
GeneratorState::Yielded(()) => amt = amt.checked_sub(1).unwrap(),
GeneratorState::Complete(ret) => {
assert_eq!(amt, 0);
return ret
}
}
}
}
fn main() {
finish(1, || yield);
finish(8, || {
for _ in 0..8 {
yield;
}
});
finish(1, || {
if true {
yield;
} else {
}
});
finish(1, || {
if false {
} else {
yield;
}
});
finish(2, || {
if { yield; false } {
yield;
panic!()
}
yield
});
}
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