I don't think we actually finished implementing this. CodaFi (JIRA User), @slavapestov?

Yeah, there are a few problems. Member reference expressions don't work either:

enum E {
  case foo(bar: ())
  case foo(baz: Int)
}

E.foo(bar: ())
E.foo(bar: 3) // error

Also we don't allow overloading on type; I think we should since we want these to behave like functions:

enum E {
  case foo(baz: String)
  case foo(baz: Int) // error
}

Finally, the more serious problem here is that for resilient enums, the mangling for the case ordinal symbol does not include argument labels. It mangles the interface type without labels, which is of the form (Enum.Type) -> (Payload) -> Enum. The correct mangling would omit the first and last components of the interface type since they don't matter, but it would include argument labels.

Doing this without breaking ABI will require adding a special attribute or build flag (which is in turn carried over to the parsable interface) to the standard library and overlays. All new code would build with the new mangling. We should fix this soon even if we don't fix the redeclaration checking or other problems, otherwise we won't be able to implement this stuff at all.

@slavapestov has any work been done on this? It seems pretty bad that I can write perfectly fine enums where the case label is the same, but on switching it breaks down completely.

struct Handler {}
struct HandlerConfig {}


enum Config {
    case `default`(handler: (String) -> Handler, other: (String) -> Handler)
    case `default`(handlerConfig: HandlerConfig)
}


func initialize(config: Config) {
    switch config {
    // These are the cases that fixit adds!
    case .default(handler: let handler, other: let other):
        // Error: Tuple pattern has the wrong length for tuple type '(handlerConfig: HandlerConfig)'
        ()
    case .default(handlerConfig: let handlerConfig):
        ()
    }
}

This makes me cry

Comment by Marco Boerner (JIRA)

Has any progress been made @slavapestov, @belkadan, CodaFi (JIRA User)? It's a long awaited for feature 🙂

Comment by Luigi Trevisi (JIRA)

Hello @slavapestov is there any update on this bug? 🙂

I have a fix for what Slava mentions, it just needs one final push then it can be merged - #31936

This bug still seems to be around (since 2019). Any plans to fix it eventually?

Any updates on this?

Any updates on the issue?