mirror of https://github.com/rust-lang/rust
53 lines
1.1 KiB
Rust
53 lines
1.1 KiB
Rust
//@ run-pass
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//@ revisions: default nomiropt
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//@[nomiropt]compile-flags: -Z mir-opt-level=0
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#![feature(coroutines, coroutine_trait, stmt_expr_attributes)]
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use std::ops::{CoroutineState, Coroutine};
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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: Coroutine<(), 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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CoroutineState::Yielded(()) => amt = amt.checked_sub(1).unwrap(),
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CoroutineState::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, #[coroutine] || yield);
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finish(8, #[coroutine] || {
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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, #[coroutine] || {
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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, #[coroutine] || {
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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, #[coroutine] || {
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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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