Match patterns can't be macros

[huonw]

E.g.

fn main() {
   match &[1,2,3] {
      bytes!("abc") => (),
      _ => ()
   }
}

pattern-macro.rs:3:11: 3:12 error: expected `=>` but found `!`
pattern-macro.rs:3       bytes!("abc") => (),
                              ^

Possibly required for #5346.

[alexcrichton]

Nominating for the feature-complete milestone. If this is going to be a feature, it sounds like a good feature to be done by then.

[catamorphism]

Accepted for feature-complete

[pnkfelix]

P-low, not 1.0.

[kmcallister]

I'm working on this.