type items do not work with enums

[AngelOfSol]

type items don't work with enums.

#[derive(Debug)]
enum Foo {
    Bar,
    Baz,
}
type Loz = Foo;
fn main() {
    let y = Loz::Bar;
    println!("{:?}", y);
}

On the stable channel the following error occurs:

<anon>:8:13: 8:21 error: type `Foo` does not implement any method in scope named `Bar`
<anon>:8     let y = Loz::Bar;
                     ^~~~~~~~
error: aborting due to previous error
playpen: application terminated with error code 101```

[arielb1]

type only creates a type alias - it does not change resolution. Maybe documentation should be improved through.

[arielb1]

The error in nightly is better:

<anon>:7:13: 7:21 error: no associated item named `Bar` found for type `Foo` in the current scope
<anon>:7     let y = Loz::Bar;

enum constructors are not associated items.

[chris-morgan]

It seems to me that it is entirely reasonable to expect this to work. It’s not just a matter of documentation.

[arielb1]

@chris-morgan

Maybe. However, associated items work rather differently from resolve-items - e.g. use Trait::Item doesn't work, but is the correct way with enums.

[steveklabnik]

/cc @rust-lang/lang, should this work, or should this give a better error?

[nikomatsakis]

I think it's a somewhat tough question. The "integration" of enum variants and other kinds of associated items is, well, there isn't any, though it sort of feels like it'd be nice if there was. I certainly think is expected behavior for the moment, and I think that any fix would require some careful thought to be sure.

[nrc]

Yeah, this is definitely not a minor fix. I'd leave as is. I guess we could document better. I would only like to see a better error message if it can be done without making name resolution more awful.

[codyps]

Similarly, associated types too can resolve constructing functions, but not enum variants: http://is.gd/pnn7sC

It'd be very convenient to be able to think about enum variants in the same way we think about type constructing functions.