Type Non-optional Optional
Bool dynamic var value = false let value = RealmOptional()
Int dynamic var value = 0 let value = RealmOptional()
Float dynamic var value: Float = 0.0 let value = RealmOptional()
Double dynamic var value: Double = 0.0 let value = RealmOptional()
String dynamic var value = "" dynamic var value: String? = nil
Data dynamic var value = Data() dynamic var value: Data? = nil
Date dynamic var value = Date() dynamic var value: Date? = nil
Object n/a: must be optional dynamic var value: Class?
List let value = List() n/a: must be non-optional
LinkingObjects let value = LinkingObjects(fromType: Class.self, property: "property")n/a: must be non-optional
