public static void WithGroups()
{
IObservable <long> ticks = Observable.Interval(TimeSpan.FromSeconds(6));
IObservable <int> wordGroupCounts = from tick in ticks
join word in words
on ticks equals words into wordsInTick
from count in wordsInTick.Count()
select count * 10;
wordGroupCounts.Subscribe(c => Console.WriteLine($"Words per minute: {c}"));
keySource.Run();
}
