Unary operator applied to range fails to parse

[dtolnay]

struct S;
impl<T> std::ops::Add<T> for S {
    type Output = ();
    fn add(self, _: T) {}
}

fn main() {
    let _ = ..0;
    let _ = S + ..0;
    let _ = &..0;
    let _ = || ..0;
    let _ = *..0;
}

With the exception of *..0, all of the above expressions parse successfully, so .. is definitely allowed to appear at the beginning of an expression — including an expression with higher precedence such as binary + and unary &. I think it is a bug that *..0 does not parse. Same for -..0 and !..0.

error: expected expression, found `..`
  --> src/main.rs:12:14
   |
12 |     let _ = *..0;
   |              ^^ expected expression