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// run-pass
// Test lifetimes are linked properly when we create dependent region pointers.
// Issue #3148.
#![feature(box_patterns)]
struct A {
value: B
}
struct B {
v1: isize,
v2: [isize; 3],
v3: Vec<isize> ,
v4: C,
v5: Box<C>,
v6: Option<C>
}
#[derive(Copy, Clone)]
struct C {
f: isize
}
fn get_v1(a: &A) -> &isize {
// Region inferencer must deduce that &v < L2 < L1
let foo = &a.value; // L1
&foo.v1 // L2
}
fn get_v2(a: &A, i: usize) -> &isize {
let foo = &a.value;
&foo.v2[i]
}
fn get_v3(a: &A, i: usize) -> &isize {
let foo = &a.value;
&foo.v3[i]
}
fn get_v4(a: &A, _i: usize) -> &isize {
let foo = &a.value;
&foo.v4.f
}
fn get_v5(a: &A, _i: usize) -> &isize {
let foo = &a.value;
&foo.v5.f
}
fn get_v6_a(a: &A, _i: usize) -> &isize {
match a.value.v6 {
Some(ref v) => &v.f,
None => panic!()
}
}
fn get_v6_b(a: &A, _i: usize) -> &isize {
match *a {
A { value: B { v6: Some(ref v), .. } } => &v.f,
_ => panic!()
}
}
fn get_v6_c(a: &A, _i: usize) -> &isize {
match a {
&A { value: B { v6: Some(ref v), .. } } => &v.f,
_ => panic!()
}
}
fn get_v5_ref(a: &A, _i: usize) -> &isize {
match &a.value {
&B {v5: box C {f: ref v}, ..} => v
}
}
pub fn main() {
let a = A {value: B {v1: 22,
v2: [23, 24, 25],
v3: vec![26, 27, 28],
v4: C { f: 29 },
v5: Box::new(C { f: 30 }),
v6: Some(C { f: 31 })}};
let p = get_v1(&a);
assert_eq!(*p, a.value.v1);
let p = get_v2(&a, 1);
assert_eq!(*p, a.value.v2[1]);
let p = get_v3(&a, 1);
assert_eq!(*p, a.value.v3[1]);
let p = get_v4(&a, 1);
assert_eq!(*p, a.value.v4.f);
let p = get_v5(&a, 1);
assert_eq!(*p, a.value.v5.f);
let p = get_v6_a(&a, 1);
assert_eq!(*p, a.value.v6.unwrap().f);
let p = get_v6_b(&a, 1);
assert_eq!(*p, a.value.v6.unwrap().f);
let p = get_v6_c(&a, 1);
assert_eq!(*p, a.value.v6.unwrap().f);
let p = get_v5_ref(&a, 1);
assert_eq!(*p, a.value.v5.f);
}
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