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#![feature(box_patterns)]
#![feature(never_type)]
#![feature(exhaustive_patterns)]
#![deny(unreachable_patterns)]
mod foo {
pub struct SecretlyEmpty {
_priv: !,
}
}
struct NotSoSecretlyEmpty {
_priv: !,
}
fn foo() -> Option<NotSoSecretlyEmpty> {
None
}
fn main() {
let x: &[!] = &[];
match x {
&[] => (),
&[..] => (), //~ ERROR unreachable pattern
};
let x: Result<Box<NotSoSecretlyEmpty>, &[Result<!, !>]> = Err(&[]);
match x {
Ok(box _) => (), //~ ERROR unreachable pattern
Err(&[]) => (),
Err(&[..]) => (), //~ ERROR unreachable pattern
}
let x: Result<foo::SecretlyEmpty, Result<NotSoSecretlyEmpty, u32>> = Err(Err(123));
match x {
Ok(_y) => (),
Err(Err(_y)) => (),
Err(Ok(_y)) => (), //~ ERROR unreachable pattern
}
while let Some(_y) = foo() {
//~^ ERROR unreachable pattern
}
}
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