Akka.Cluster.ClusterEvent.DiffReachability C# (CSharp) Method

        internal static ImmutableList<ReachabilityChanged> DiffReachability(Gossip oldGossip, Gossip newGossip)
        {
            if (newGossip.Overview.Reachability.Equals(oldGossip.Overview.Reachability))
                return ImmutableList.Create<ReachabilityChanged>();

            return ImmutableList.Create(new ReachabilityChanged(newGossip.Overview.Reachability));
        }
    }

 private void PublishDiff(Gossip oldGossip, Gossip newGossip, Action <object> pub)
 {
     foreach (var @event in ClusterEvent.DiffMemberEvents(oldGossip, newGossip))
     {
         pub(@event);
     }
     foreach (var @event in ClusterEvent.DiffUnreachable(oldGossip, newGossip))
     {
         pub(@event);
     }
     foreach (var @event in ClusterEvent.DiffReachable(oldGossip, newGossip))
     {
         pub(@event);
     }
     foreach (var @event in ClusterEvent.DiffLeader(oldGossip, newGossip, _selfUniqueAddress))
     {
         pub(@event);
     }
     foreach (var @event in ClusterEvent.DiffRolesLeader(oldGossip, newGossip, _selfUniqueAddress))
     {
         pub(@event);
     }
     // publish internal SeenState for testing purposes
     foreach (var @event in ClusterEvent.DiffSeen(oldGossip, newGossip, _selfUniqueAddress))
     {
         pub(@event);
     }
     foreach (var @event in ClusterEvent.DiffReachability(oldGossip, newGossip))
     {
         pub(@event);
     }
 }