fn main() {
    match Some(vec![3]) {
        Some(vec![x]) => (),
        _ => (),
    }
}

error: unexpected `(` after qualified path
 --> src/main.rs:3:14
  |
3 |         Some(vec![x]) => (),
  |              ^^^^^^^
  |              |
  |              unexpected `(` after qualified path
  |              in this macro invocation
  |
  = note: this warning originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)