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#![feature(generators, generator_trait)]
use std::ops::{GeneratorState, Generator};
use std::cell::Cell;
use std::pin::Pin;
fn yield_during_iter_owned_data(x: Vec<i32>) {
// The generator 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 = move || {
for p in &x { //~ ERROR
yield();
}
};
}
fn yield_during_iter_borrowed_slice(x: &[i32]) {
let _b = move || {
for p in x {
yield();
}
};
}
fn yield_during_iter_borrowed_slice_2() {
let mut x = vec![22_i32];
let _b = || {
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 = || {
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 = || {
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 = || {
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() { }
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