Enum element cannot be referenced as an instance member

Question

I'm creating an API layer using Moya and keep getting the above mentioned error for the .updateMyWeightGoal target when I'm creating a request for an endpoint.

    goalAPI.request(target:  .updateMyWeightGoal(weightGoalData: goalInfo),  success: { (response) in
        //
    }){ (response: [String : Any]) in
        print(response)
    }

I've created another Moya API of the same type and am calling it using the same goalAPI as this and it's working fine.

Any ideas what might be causing this issue

For reference here is the class definition for the weightGoalData type

class UpdatedWeightGoalInfo: Mappable {

var consumerUserID: Int?
var height: String?
var weight: String?
var goalWeight: String?

init() {

}

convenience init(userId: Int, weightGoalData: WeightGoalResponse) {
    self.init()
    consumerUserID = userId
    height = "\(weightGoalData.currentHeight)"
    weight = "\(weightGoalData.currentWeight)"
    goalWeight = "\(weightGoalData.goalWeight)"
}

required init?(map: Map) {
}

func mapping(map: Map) {
    consumerUserID <- map["consumerUserId"]
    height <- map["height"]
    weight <- map["weight"]
    goalWeight <- map["goalWeight"]
}
}

And the definition of the API:

enum GoalSettingAPI: AccessTokenAuthorizable {

  case updateMyWeightGoal(weightGoalData: UpdatedWeightGoalInfo)
}

extension GoalSettingAPI: TargetType {
var parameterEncoding: ParameterEncoding {
    switch self {
    default:
        return JSONEncoding.default
    }
}

var baseURL: URL { return URL(string: appBaseURL + "*hidden*/")! }
var path: String {
    switch self {
    case .updateMyWeightGoal(_):
        return "updateMyWeightGoal"
    }
}

var method: Moya.Method {
    switch self {
    case .updateMyWeightGoal(_):
        return .post
    }
}

var parameters: [String: Any]? {
    switch self {
    case .updateMyWeightGoal(let weightGoalData):
        return weightGoalData.toJSON()
    }
}

var sampleData: Data {
    switch self {
    default:
        return Data()
    }
}

var task: Task {
    switch self {
    default:
        return .request
    }
}

var shouldAuthorize: Bool {
    switch self {
    default:
        return false
    }
}
}

Please show where `.updateMyWeightGoal` and `goalAPI.request` is defined. — Oskar, Apr 28 '17 at 10:48
@Oskar: Okay, added those in. And goalAPI.request is working fine as I'm using another API from the same group which is not giving me any trouble — Suman Roy, Apr 28 '17 at 10:53

score 33 · Accepted Answer · answered Apr 30 '17 at 05:40

33

This is the stupidest thing.

As it turns out the error was coming, not from the enum, but from the success block. It was expecting an object of type Mappable, which I wasn't providing.

answered Apr 30 '17 at 05:40

Suman Roy

673
5
18

3

Similar thing just happened to me, I got this error in a ternary expression but it was actually because I forgot to finish the comparison in the first part (`int ? .foo : .bar` instead of `int > 0 ? .foo : .bar`). Much as I like Swift, its compiler messages still leave a lot to be desired. – John Montgomery May 03 '18 at 22:30
Yeah, Xcode in recent years is less and less helpful with his error/warning messages... – Soberman May 09 '18 at 11:19
Yea a similar thing happened to me. I was trying to use the tertiary operator to set a state value to an enum case, but my conditional value couldn't actually resolve to true or false, so it gave the enum error as you described. Not entirely helpful. – Acadian_Ghost Jul 19 '19 at 13:41
I forgot to put dots before enum cases. Like "case one:" instead of "case .one:" – Roman Dec 02 '21 at 12:56

score 5 · Answer 2 · answered Apr 28 '17 at 11:00

5

You're referring to .updateMyWeightGoal as an instance member (.) when it is declared as an enum. Try changing:

goalAPI.request(target: .updateMyWeightGoal(weightGoalData: goalInfo)

To

goalAPI.request(target: GoalSettingAPI.updateMyWeightGoal(weightGoalData: goalInfo)

answered Apr 28 '17 at 11:00

Oskar

3,625
2
29
37

Doing this is throwing `Ambiguous reference to member 'print(_:separator:terminator:)'` for the print statement in the failure block. – Suman Roy Apr 28 '17 at 11:19
1

Change it to `Swift.print`. – Oskar Apr 28 '17 at 11:40
Thanks for the help, but I just found the issue. – Suman Roy Apr 30 '17 at 05:41
1

@Oskar Thanks! you made my day! – Tommy Dec 21 '20 at 10:03

score 1 · Answer 3 · answered Dec 17 '18 at 17:56

Had the same error. In my case the issue was that I had typed:

if someVariable = .AnEnumValue

What I meant was:

if someVariable == .AnEnumValue

The key difference being = vs ==.

Not sure how the compiler landed on this particular error message, but this fixed the problem.

Enum element cannot be referenced as an instance member

3 Answers3