mirror of https://github.com/rust-lang/rust
76 lines
1.7 KiB
Rust
76 lines
1.7 KiB
Rust
#![feature(coroutines, coroutine_trait, stmt_expr_attributes)]
|
|
|
|
use std::ops::{CoroutineState, Coroutine};
|
|
use std::cell::Cell;
|
|
use std::pin::Pin;
|
|
|
|
fn yield_during_iter_owned_data(x: Vec<i32>) {
|
|
// The coroutine owns `x`, so we error out when yielding with a
|
|
// reference to it. This winds up becoming a rather confusing
|
|
// regionck error -- in particular, we would freeze with the
|
|
// reference in scope, and it doesn't live long enough.
|
|
let _b =#[coroutine] move || {
|
|
for p in &x { //~ ERROR
|
|
yield();
|
|
}
|
|
};
|
|
}
|
|
|
|
fn yield_during_iter_borrowed_slice(x: &[i32]) {
|
|
let _b = #[coroutine] move || {
|
|
for p in x {
|
|
yield();
|
|
}
|
|
};
|
|
}
|
|
|
|
fn yield_during_iter_borrowed_slice_2() {
|
|
let mut x = vec![22_i32];
|
|
let _b = #[coroutine] || {
|
|
for p in &x {
|
|
yield();
|
|
}
|
|
};
|
|
println!("{:?}", x);
|
|
}
|
|
|
|
fn yield_during_iter_borrowed_slice_3() {
|
|
// OK to take a mutable ref to `x` and yield
|
|
// up pointers from it:
|
|
let mut x = vec![22_i32];
|
|
let mut b = #[coroutine] || {
|
|
for p in &mut x {
|
|
yield p;
|
|
}
|
|
};
|
|
Pin::new(&mut b).resume(());
|
|
}
|
|
|
|
fn yield_during_iter_borrowed_slice_4() {
|
|
// ...but not OK to do that while reading
|
|
// from `x` too
|
|
let mut x = vec![22_i32];
|
|
let mut b = #[coroutine] || {
|
|
for p in &mut x {
|
|
yield p;
|
|
}
|
|
};
|
|
println!("{}", x[0]); //~ ERROR
|
|
Pin::new(&mut b).resume(());
|
|
}
|
|
|
|
fn yield_during_range_iter() {
|
|
// Should be OK.
|
|
let mut b = #[coroutine] || {
|
|
let v = vec![1,2,3];
|
|
let len = v.len();
|
|
for i in 0..len {
|
|
let x = v[i];
|
|
yield x;
|
|
}
|
|
};
|
|
Pin::new(&mut b).resume(());
|
|
}
|
|
|
|
fn main() { }
|