Error message could be improved in generic match arm

[srinivasreddy]

In the following program instead of underscore, i put a hyphen. The error message i received is misleading. I think it can be improved. What do you guys think?

fn main() {
   let integer = 2;
   match integer {
    2 => { println!("this is two");}
    - => { println!("This is Not two"); }
    }
}

srinivas@Srini:~/workspace/github/rust-exercises$ rustc 3.rs
3.rs:5:7: 5:9 error: expected pattern, found `=>`
3.rs:5     - => { println!("This is None"); }
             ^~
error: aborting due to 2 previous errors

Here is the playpen

[estebank]

I think this is because it is expecting a number (the pattern it couldn't find) after the -. I believe this might have to be special cased to point at the - instead of the =>.

[estebank]

Duplicate of #29586.