var xs = Observable.Interval(TimeSpan.FromSeconds(0.5)).Publish().RefCount();
var zs = xs.Buffer(xs.Sample(TimeSpan.FromSeconds(1.5)), x => xs.Skip(5).Take(1));

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Reactive.Linq;
using System.Reactive.Concurrency;
using System.Reactive.Disposables;
using System.Threading.Tasks;
 
namespace Sela.Samples

public static IObservable<EventPattern<PropertyChangedEventArgs>> WhereProperty<TProperty>
     (this IObservable<EventPattern<PropertyChangedEventArgs>> propChangedEvent, Expression<Func<TProperty>> property)
 {
     return
         propChangedEvent.Where(
             pce => pce.EventArgs.PropertyName == property.GetMemberInfo().Name);
 }
 
 public static IObservable<EventPattern<PropertyChangedEventArgs>> PropertyChanges(this INotifyPropertyChanged notifier)
 {