JS Bin

var interval = Rx.Observable.interval(1000);

​

var source = interval

    .take(4)

    .doAction(function (x) { 

        console.log('Side effect');

    });

var published = source

    .shareReplay(3);

published.subscribe(createObserver('SourceA'));

published.subscribe(createObserver('SourceB'));

​

// Creating a third subscription after the previous two subscriptions have 

// completed. Notice that no side effects result from this subscription, 

// because the notifications are cached and replayed. 

Rx.Observable

    .return(true)

    .delay(6000)

    .flatMap(published)

    .subscribe(createObserver('SourceC'));

function createObserver(tag) {

    return Rx.Observer.create(

        function (x) {

            console.log('Next: ' + tag + x);

        },

        function (err) {

            console.log('Error: ' + err);   

        },

        function () {

            console.log('Completed');   

        });

}

​

// => Side effect

// => Next: SourceA0

// => Next: SourceB0

// => Side effect

// => Next: SourceA1

// => Next: SourceB1

// => Side effect

// => Next: SourceA2

// => Next: SourceB2

// => Side effect

// => Next: SourceA3

// => Next: SourceB3

// => Completed

// => Completed

// => Next: SourceC1

// => Next: SourceC2

// => Next: SourceC3

// => Completed