Error: identifier is bound more than once in the same pattern when using match and mod

[blastrock]

Hi,

Here is a strange bug I came across:

use m::EntityType;

mod m {
    pub enum EntityType {
        Type1,
        Type2,
    }
}

fn do_match(t1: EntityType, t2: EntityType) {
    match (t1, t2) {
        (Type1, Type1) => (),
        (Type2, Type2) => (),
        (Type1, Type2) => (),
        (Type2, Type1) => (),
    }
}

fn main() {}

This code fails to compile with:

<anon>:12:17: 12:22 error: identifier `Type1` is bound more than once in the same pattern
<anon>:12         (Type1, Type1) => (),
                          ^~~~~
<anon>:13:17: 13:22 error: identifier `Type2` is bound more than once in the same pattern
<anon>:13         (Type2, Type2) => (),
                          ^~~~~
error: aborting due to 2 previous errors
playpen: application terminated with error code 101

But it works if we remove the mod block and the use statement, thus putting EntityType in the same namespace.

Tested on master

[sfackler]

The Type1 variant isn't in scope in your match, so it's being interpreted as a variable to bind the value of t1.

[blastrock]

Ohhhhh I get it!
So I needed to specify also "use m::{Type1, Type2}". Sorry for the false report then.

[blastrock]

And thank you!