with-latest-from doesn't take multiple others.

[luminusian]

withLatestFrom in RxJS and RxJava can take multiple others.

https://github.com/Reactive-Extensions/RxJS/blob/master/doc/api/core/operators/withlatestfrom.md

ReactiveX/RxJava#3966

http://reactivex.io/RxJava/javadoc/rx/Observable.html#withLatestFrom(java.lang.Iterable,%20rx.functions.FuncN)

[niwinz]

We are not using rxjs 4.x, the 5.x does not allows multiple observables (http://reactivex.io/rxjs/class/es6/Observable.js~Observable.html#instance-method-withLatestFrom)

I know that the jvm allows it, but it is normalized to one observable for bot impl.