Anyone have any insights to encoding/decoding double linked lists with JSON? This is just the pertinent part of the class.

If I leave off the parent var, then the application (Document Based SwiftUI) saves and loads fine - no problems (except of course the parent functionality is lost).

public class Sidebar: Codable, ObservableObject, Identifiable {

    public let objectWillChange = ObservableObjectPublisher()

    enum CodingKeys: CodingKey {
        case id
        case parent
        case children
    }

    public func encode(to encoder: Encoder) throws {
        var container = encoder.container(keyedBy: CodingKeys.self)

        try container.encode(id, forKey: .id)
        try container.encode(parent, forKey: .parent)
        try container.encode(children, forKey: .children)
    }

    public required init(from decoder: Decoder) throws {
        let container = try decoder.container(keyedBy: CodingKeys.self)

        id = UUID()
        parent = try container.decode(Sidebar?.self, forKey: .parent)
        children = try container.decode([Sidebar]?.self, forKey: .children)
    }

    @Published  public var id: UUID?
    @Published  public var parent: Sidebar?
    @Published  public var children: [Sidebar]?

    public init() {
        id = UUID()
    }

With the parent var inserted and working (linked) the app crashes when saving during this call with a bad access error:

  public func encode(to encoder: Encoder) throws {

      var singleContainer = encoder.singleValueContainer()

      try singleContainer.encode(NSKeyedArchiver.archivedData(withRootObject: attrString, requiringSecureCoding: false))
  }

It appears circular referenses give JSON indigestion.

Suggestions?