Compound key in Realm with lazy property

问题

I found this great solution for using Realm with compound primary key in Swift: https://github.com/realm/realm-cocoa/issues/1192

public final class Card: Object {
  public dynamic var id = 0 {
      didSet {
          compoundKey = compoundKeyValue()
      }
  }
  public dynamic var type = "" {
      didSet {
          compoundKey = compoundKeyValue()
      }
  }
  public dynamic lazy var compoundKey: String = self.compoundKeyValue()
  public override static func primaryKey() -> String? {
      return "compoundKey"
  }

  private func compoundKeyValue() -> String {
      return "\(id)-\(type)"
  }
}

But I discovered that Realm does not support lazy properties, in my case I receive this error:

exception NSException * name: "RLMException" - reason: "Lazy managed property 'compoundKey' is not allowed on a Realm Swift object class. Either add the property to the ignored properties list or make it non-lazy." 0x00007f8a05108060

Is it still possible to have compound key without lazy property?

回答1:

The solution you found is outdated. I'll leave a note about that there. I'd suggest removing the lazy modifier and initializing compoundKey to an empty string.

来源：https://stackoverflow.com/questions/38010548/compound-key-in-realm-with-lazy-property