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// edition:2021
// run-pass
// Test precise capture when using boxes
struct MetaData { x: String, name: String }
struct Data { m: MetaData }
struct BoxedData(Box<Data>);
struct EvenMoreBoxedData(Box<BoxedData>);
// Mutate disjoint paths, one inside one outside the closure
fn box_1() {
let m = MetaData { x: format!("x"), name: format!("name") };
let d = Data { m };
let b = BoxedData(Box::new(d));
let mut e = EvenMoreBoxedData(Box::new(b));
let mut c = || {
e.0.0.m.x = format!("not-x");
};
e.0.0.m.name = format!("not-name");
c();
}
// Mutate a path inside the closure and read a disjoint path outside the closure
fn box_2() {
let m = MetaData { x: format!("x"), name: format!("name") };
let d = Data { m };
let b = BoxedData(Box::new(d));
let mut e = EvenMoreBoxedData(Box::new(b));
let mut c = || {
e.0.0.m.x = format!("not-x");
};
println!("{}", e.0.0.m.name);
c();
}
// Read a path inside the closure and mutate a disjoint path outside the closure
fn box_3() {
let m = MetaData { x: format!("x"), name: format!("name") };
let d = Data { m };
let b = BoxedData(Box::new(d));
let mut e = EvenMoreBoxedData(Box::new(b));
let c = || {
println!("{}", e.0.0.m.name);
};
e.0.0.m.x = format!("not-x");
c();
}
// Read disjoint paths, one inside the closure and one outside the closure.
fn box_4() {
let m = MetaData { x: format!("x"), name: format!("name") };
let d = Data { m };
let b = BoxedData(Box::new(d));
let e = EvenMoreBoxedData(Box::new(b));
let c = || {
println!("{}", e.0.0.m.name);
};
println!("{}", e.0.0.m.x);
c();
}
// Read the same path, once inside the closure and once outside the closure.
fn box_5() {
let m = MetaData { x: format!("x"), name: format!("name") };
let d = Data { m };
let b = BoxedData(Box::new(d));
let e = EvenMoreBoxedData(Box::new(b));
let c = || {
println!("{}", e.0.0.m.name);
};
println!("{}", e.0.0.m.name);
c();
}
fn main() {
box_1();
box_2();
box_3();
box_4();
box_5();
}
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