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// run-pass
// Test that we mutate a counter on the stack only when we expect to.
fn call<F>(f: F) where F : FnOnce() {
f();
}
fn main() {
let y = vec![format!("Hello"), format!("World")];
let mut counter = 22_u32;
call(|| {
// Move `y`, but do not move `counter`, even though it is read
// by value (note that it is also mutated).
for item in y { //~ WARN unused variable: `item`
let v = counter;
counter += v;
}
});
assert_eq!(counter, 88);
call(move || {
// this mutates a moved copy, and hence doesn't affect original
counter += 1; //~ WARN value assigned to `counter` is never read
//~| WARN unused variable: `counter`
});
assert_eq!(counter, 88);
}
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