groupBy<S> method

Observable<GroupByObservable<T, S>> groupBy <S>(S grouper(T value))

The GroupBy operator divides an Observable that emits items into an Observable that emits GroupByObservable, each one of which emits some subset of the items from the original source Observable.

GroupByObservable acts like a regular Observable, yet adding a 'key' property, which receives its Type and value from the grouper Function.

All items with the same key are emitted by the same GroupByObservable.


Observable<GroupByObservable<T, S>> groupBy<S>(S grouper(T value)) =>
    transform(GroupByStreamTransformer<T, S>(grouper));