javascript - RxJS 1 array item into sequence of single items

given such observable

rx.observable.of([1,2,3,4,5])

which emits single item (that array), what operator transform observable 1 emits 5 single items (or whatever array consists of)?

the example on .of, same fetching arrays via promises, there might many other examples. don't suggest replace of from

i can't think of existing operator that, can make 1 :

arrayemitting$.concatmap(arrayvalues => rx.observable.merge(arrayvalues.map(rx.observable.of)))

or simpler

arrayemitting$.concatmap(rx.observable.of)

or shortest

arrayemitting$.concatmap(x => x)

that untested let me know if worked you, , uses rxjs v4 api (specially last one). :

process each incoming array of values 1 unit (meaning next incoming array not interlap previous 1 - why use concatmap)
the incoming array transformed array of observables, merged : ensures emission of values separately , in sequence

MOno