Sum operator is not implemented about lightweight-stream-api

[aNNiMON]

@yanbraslavsky-home24 thank you for the feedback. I did not add these methods, because they can be easily implemented by existing library functions. Otherwise it would not be a lightweight library 😀

int sum = Stream.ofRange(1, 9).reduce(0, new BinaryOperator<Integer>() {
    @Override
    public Integer apply(Integer value1, Integer value2) {
        return value1 + value2;
    }
});

[yanbraslavsky-home24]

That is exactly how I have implemented it.Just for my convinience I wanted them to be in the library. Maybe I'll fork it then ;)
P.S.
Any plan for parallel ?

[aNNiMON]

@yanbraslavsky-home24 no, it's hard to implement parallel processing with Iterators. Java 8 uses Spliterators for this.