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// check-fail
use std::fmt::{self, Display};
struct Mutex;
impl Mutex {
fn lock(&self) -> MutexGuard {
MutexGuard(self)
}
}
struct MutexGuard<'a>(&'a Mutex);
impl<'a> Drop for MutexGuard<'a> {
fn drop(&mut self) {
// Empty but this is a necessary part of the repro. Otherwise borrow
// checker is fine with 'a dangling at the time that MutexGuard goes out
// of scope.
}
}
struct Out;
impl Out {
fn write_fmt(&self, _args: fmt::Arguments) {}
}
impl<'a> Display for MutexGuard<'a> {
fn fmt(&self, _formatter: &mut fmt::Formatter) -> fmt::Result {
Ok(())
}
}
fn main() {
// FIXME(dtolnay): We actually want both of these to work. I think it's
// sadly unimplementable today though.
let _write = {
let mutex = Mutex;
write!(Out, "{}", mutex.lock()) /* no semicolon */
//~^ ERROR `mutex` does not live long enough
};
let _writeln = {
let mutex = Mutex;
writeln!(Out, "{}", mutex.lock()) /* no semicolon */
//~^ ERROR `mutex` does not live long enough
};
}
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