using System;
using System.Reactive.Linq;
using System.Reactive.Subjects;

public class BasicMessageBus
{
    private static readonly BasicMessageBus _instance = new();
    public static BasicMessageBus Inst => _instance;

    private readonly Subject<object> _messages = new();
    public IObservable<T> Subscribe<T>() => _messages.OfType<T>();
    public void Send(object message) => _messages.OnNext(message);
}