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// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
#![feature(generators, generator_trait)]
use std::ops::{GeneratorState, Generator};
use std::cell::Cell;
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;
}
};
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
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;
}
};
b.resume();
}
fn main() { }
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