Encoding and decoding enum with no associated values in Swift

Question

Created Sep ’20

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Hullo, I need to encode and decode a simple enum with no associated values, but I only find examples with associated values and someone say a bare enum would be automatically Codable, what the compiler does not agree upon. This is my code sale that looks very clumsy, though:

Code Block enum MeditationItem: Codable, CodingKey{
case morning
case evening
case dropIn
case dropOut
case intermediate
case single
case supported
case walking
func nameForKind()->String{
    switch self{
    case .morning: return "Morning"
    case .evening: return "Evening"
    case .dropIn: return "dropIn"
    case .dropOut: return "dropOut"
    case .intermediate: return "intermediate"
    case .single: return "Single"
    case .supported: return "Supported"
    case .walking: return "Walking"
    }
}
init(from decoder: Decoder) throws {
    do {
        let container = try decoder.container(keyedBy: MeditationItem.self)
        do {
            let morning = try container.decode(MeditationItem.self, forKey: .morning)
            self=morning
        } catch {
            let evening = try container.decode(MeditationItem.self, forKey: .evening)
            self=evening
        }
    
}

What is the most sleek way to encode and decode an enum with no associated values?

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Answer 1

OOPer OP

Sep ’20

Just add raw value type to the definition.

Code Block enum MeditationItem: Int, Codable, CodingKey{ //<- Please do not miss `Int` in this line.
    case morning
    case evening
    case dropIn
    case dropOut
    case intermediate
    case single
    case supported
    case walking
    func nameForKind()->String{
        switch self{
        case .morning: return "Morning"
        case .evening: return "Evening"
        case .dropIn: return "dropIn"
        case .dropOut: return "dropOut"
        case .intermediate: return "intermediate"
        case .single: return "Single"
        case .supported: return "Supported"
        case .walking: return "Walking"
        }
    }
}

You can use String if you prefer:

Code Block enum MeditationItem: String, Codable {
    case morning = "Morning"
    case evening = "Evening"
    case dropIn
    case dropOut
    case intermediate
    case single = "Single"
    case supported = "Supported"
    case walking = "Walking"
    func nameForKind() -> String {
        return self.rawValue
    }
}

I do not understand why you added conformance to CodingKey, so I keep it in the example code above, but do you really need it?

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