RxSyncTimeout.cs

gistfile1.txt

        public static IObservable<TResult> SyncTimeout<TSource, TResult>(this IObservable<TSource> first,
            IObservable<TSource> second, TimeSpan dueTime, Func<TSource, TSource, TResult> selectorFunc)
        {
            return
                first
                    .Zip(second.Timeout(dueTime).Take(1), (f, s) => new {First = f, Second = s})
                    .Repeat()
                    .Select(x => selectorFunc(x.First, x.Second));
        }