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Unexpected cold observed behavior

I thought I understood the difference between a cold and a hot Observed, but something seems to be slipping away from me. This code works as expected:

var obs = Rx.Observable.interval(2000);

var A = obs.subscribe(function(value) { console.log('A', value) });
var B = obs.subscribe(function(value) { console.log('B', value) });

With this, I get the following result:

A 0
B 0
A 1
B 1
...

But when I add flatMapto retrieve the remote JSONP resource:

var obs = Rx.Observable.interval(2000).flatMap(function() {
  return Rx.DOM.jsonpRequest({ url: URL });
})
.map(function(value) { return value.prop; });

var A = obs.subscribe(function(value) { console.log('A', value) });
var B = obs.subscribe(function(value) { console.log('B', value) });

I get only Alogs:

A prop
A prop
A prop
...

If you turn Observable into hot using publish().refCount(), it works as I would expect both subscribers to get the same values.

Now I realize that by observing that it is cold, I do not expect to get the same value at the same time, but I would expect that both the observer Aand Breceive values rather than only A.

What am I missing here?

+4
1

RxJs-DOM, . , , URL :

return Rx.DOM.jsonpRequest(URL);

: , , . , defer :

return Rx.Observable.defer(function () { return Rx.DOM.jsonpRequest({ url: URL }); });
+1

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