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// check drop order of temporaries create in match guards.
// For normal guards all temporaries are dropped before the body of the arm.
// For let guards temporaries live until the end of the arm.
//@ run-pass
#![feature(if_let_guard)]
#![allow(irrefutable_let_patterns)]
use std::sync::Mutex;
static A: Mutex<Vec<i32>> = Mutex::new(Vec::new());
struct D(i32);
fn make_d(x: i32) -> D {
A.lock().unwrap().push(x);
D(x)
}
impl Drop for D {
fn drop(&mut self) {
A.lock().unwrap().push(!self.0);
}
}
fn if_guard(num: i32) {
let _d = make_d(1);
match num {
1 | 2 if make_d(2).0 == 2 => {
make_d(3);
}
_ => {}
}
}
fn if_let_guard(num: i32) {
let _d = make_d(1);
match num {
1 | 2 if let D(ref _x) = make_d(2) => {
make_d(3);
}
_ => {}
}
}
fn main() {
if_guard(1);
if_guard(2);
if_let_guard(1);
if_let_guard(2);
let expected = [
1, 2, !2, 3, !3, !1,
1, 2, !2, 3, !3, !1,
1, 2, 3, !3, !2, !1,
1, 2, 3, !3, !2, !1,
];
assert_eq!(*A.lock().unwrap(), expected);
}
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