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// run-pass
// needs-unwind
use std::cell::RefCell;
use std::panic;
pub struct DropLogger<'a> {
id: usize,
log: &'a panic::AssertUnwindSafe<RefCell<Vec<usize>>>
}
impl<'a> Drop for DropLogger<'a> {
fn drop(&mut self) {
self.log.0.borrow_mut().push(self.id);
}
}
struct InjectedFailure;
#[allow(unreachable_code)]
fn main() {
let log = panic::AssertUnwindSafe(RefCell::new(vec![]));
let d = |id| DropLogger { id: id, log: &log };
let get = || -> Vec<_> {
let mut m = log.0.borrow_mut();
let n = m.drain(..);
n.collect()
};
{
let _x = (d(0), &d(1), d(2), &d(3));
// all borrows are extended - nothing has been dropped yet
assert_eq!(get(), vec![]);
}
// in a let-statement, extended places are dropped
// *after* the let result (tho they have the same scope
// as far as scope-based borrowck goes).
assert_eq!(get(), vec![0, 2, 3, 1]);
let _ = std::panic::catch_unwind(|| {
(d(4), &d(5), d(6), &d(7), panic::panic_any(InjectedFailure));
});
// here, the temporaries (5/7) live until the end of the
// containing statement, which is destroyed after the operands
// (4/6) on a panic.
assert_eq!(get(), vec![6, 4, 7, 5]);
}
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