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// edition:2021
// run-pass
// Test that move closures compile properly with `capture_disjoint_fields` enabled.
#![allow(unused)]
fn simple_ref() {
let mut s = 10;
let ref_s = &mut s;
let mut c = move || {
*ref_s += 10;
};
c();
}
fn struct_contains_ref_to_another_struct() {
struct S(String);
struct T<'a>(&'a mut S);
let mut s = S("s".into());
let t = T(&mut s);
let mut c = move || {
t.0.0 = "new s".into();
};
c();
}
#[derive(Debug)]
struct S(String);
#[derive(Debug)]
struct T(S);
fn no_ref() {
let mut t = T(S("s".into()));
let mut c = move || {
t.0.0 = "new S".into();
};
c();
}
fn no_ref_nested() {
let mut t = T(S("s".into()));
let c = || {
println!("{:?}", t.0);
let mut c = move || {
t.0.0 = "new S".into();
println!("{:?}", t.0.0);
};
c();
};
c();
}
// Test that even if a path is moved into the closure, the closure is not FnOnce
// if the path is not moved by the closure call.
fn data_moved_but_not_fn_once() {
let x = Box::new(10i32);
let c = move || {
// *x has type i32 which is Copy. So even though the box `x` will be moved
// into the closure, `x` is never moved when the closure is called, i.e. the
// ownership stays with the closure and therefore we can call the function multiple times.
let _x = *x;
};
c();
c();
}
// Test that move closures can take ownership of Copy type
fn returned_closure_owns_copy_type_data() -> impl Fn() -> i32 {
let x = 10;
let c = move || x;
c
}
fn main() {
simple_ref();
struct_contains_ref_to_another_struct();
no_ref();
no_ref_nested();
data_moved_but_not_fn_once();
returned_closure_owns_copy_type_data();
}
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