// JS
        // Keep these value in sync with subscription_state.hpp
        realmConstructor.Sync.SubscriptionState = {
            Error: -1,      // An error occurred while creating or processing the partial sync subscription.
            Creating: 2,    // The subscription is being created.
            Pending: 0,     // The subscription was created, but has not yet been processed by the sync server.
            Complete: 1,    // The subscription has been processed by the sync server and data is being synced to the device.
            Invalidated: 3, // The subscription has been removed.
        };

// TypeScript
    enum SubscriptionState {
         Error,
         Creating,
         Pending,
         Complete,
         Invalidated,
    }

// JS
    /**
     * Gets the current state of the session.
     * Can be either:
     *  - "active": The session is connected to the Realm Object Server and is actively transferring data.
     *  - "inactive": The session is not currently communicating with the Realm Object Server.
     *  - "invalid": A non-recoverable error has occurred, and this session is semantically invalid. A new session should be created.
     * @type {string}
     */
    get state() {}

// TypeScript:
        readonly state: 'invalid' | 'active' | 'inactive';

// JS
    /**
     * Gets the current state of the connection to the server. Multiple sessions might share the same underlying
     * connection. In that case, any connection change is sent to all sessions.
     *
     * Can be either:
     *  - Realm.Sync.ConnectionState.Disconnected: No connection to the server is available.
     *  - Realm.Sync.ConnectionState.Connecting: An attempt to connect to the server is in progress.
     *  - Realm.Sync.ConnectionState.Connected: The connection to the server is active and data can be synchronized.
     *
     * Data will only be synchronized with the Realm ObjectServer if this method returns `Connected` and `state()`
     * returns `Active` or `Dying`.
     *
     * @type {string}
     */
    connectionState() {}

// TypeScript
    enum ConnectionState {
        Disconnected = "disconnected",
        Connecting = "connecting",
        Connected = "connected",
    }