Incorrect "non-exhaustive patterns" using @-binding in match

[bluss]

Binding a match arm using "as-patterns" ref x @ or ref mut x @ will emit an incorrect error message.

rusti:  match Some(1) { ref x@Some(*) => 1, None => 0 }
<anon>:5:10: 5:57 error: non-exhaustive patterns
<anon>:5           match Some(1) { ref x@Some(*) => 1, None => 0 }
                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

rustc will be silent and happy if a third case _ => fail!() is provided.

[catamorphism]

Reproduced with 16b8a41 . Unfortunate, but not a milestone blocker IMO.

[edwardw]

Not an issue any more. The following compiles happily:

pub fn main() {
  let _x = match Some(1) {
    _y @ Some(_) => 1,
    None => 2,
  };
}

[alexcrichton]

Flagging as needstest

[chris-morgan]

I just hit this, and it is an issue which still fails. @edwardw, you missed the key fact in the initial report: the usage of ref as well as @. @ without ref or ref mut is fine.

Can we please reopen this issue?

[huonw]

Test case:

pub fn main() {
  let _x = match Some(1) {
    ref _y @ Some(_) => 1,
    None => 2,
  };
}

[edwardw]

Ah, my bad to misread the original ticket. Obliged to fix it then :)