public static void Run()
{
{
// IObservable<TSource> Aggregate<TSource>(
// this IObservable<TSource> source,
// Func<TSource, TSource, TSource> accumulator)
var numbers = Observable.Range(0, 10);
var sum = numbers.Aggregate(0, (acc, currentValue) => acc + currentValue);
sum.Dump("sum");
// problem
// 1. must be same type, 2. need at least one value
}
{
// IObservable<TAccumulate> Aggregate<TSource, TAccumulate>(
// this IObservable<TSource> source,
// TAccumulate seed,
// Func<TAccumulate, TSource, TAccumulate> accumulator)
var chars = new Char[] { 'a', 'b', 'c' }.ToObservable();
var count = chars.Aggregate(0, (acc, _) => acc + 1);
count.Dump("count");
}
{
//
var numbers = new Subject<int>();
var scan = numbers.Scan(0, (acc, current) => acc + current);
numbers.Dump("numbers");
scan.Dump("scan");
numbers.OnNext(1);
numbers.OnNext(2);
numbers.OnNext(3);
numbers.OnCompleted();
// source.Aggregate(0, (acc, current) => acc + current);
// is equivalent to
// source.Scan(0, (acc, current) => acc + current).TakeLast();
}
}