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