fn f() {
    match a {
        Some(_) => true,
        a => true,
        ref mut a => true,
        a @ 1...5 => true,
        Some(b) => true,
        Some(..) => true,
        <T as Trait>::CONST => true,
        a::CONST => true,
        A { x: bool, y : B { y1, y2 }, ref mut z, .. } => true,
        (a, b) => true,
        box a => true,
        &mut a => true,
        1 => true,
        1...3 => true,
        [a, b, .., d, e] => true,
        [..] => true,
        a!() => true,
    }
}