How can I save variables with value type Measurement<UnitType> using Realm Swift?

Question

Does Realm Swift support saving and retrieving data with value type Measurement? Here is the class structure of the data I'm trying to save:

class Race: Object {
@objc dynamic var raceDistance: Measurement<UnitLength>?
@objc dynamic var nettTime = Measurement<UnitDuration>?
}

Answer 1

Measurements themselves are not supported by Realm, but they conform to Codable, so you can save an encoded version of them:

@objc dynamic var encodedRaceDistance: Data?
// Realm 10.10+
// @Persisted var encodedRaceDistance: Data?

And you can add a computed property like this to get the Measurement<UnitLength> from the data:

var raceDistanceMeasurement: Measurement<UnitLength>? {
    get {
        if let encoded = encodedRaceDistance {
            return try? JSONDecoder().decode(Measurement<UnitLength>.self, from: encoded)
        }
        return nil
    }
    
    set {
        if let newValue = newValue {
            encodedRaceDistance = try? JSONEncoder().encode(newValue)
        } else {
            encodedRaceDistance = nil
        }
    }
}