how to decide if viewer is a network member

[Nathan Finstein]

found sample code on this forum including this snippet: "if (ning.CurrentProfile == null) {"
But I could not find any documentation on the "ning" object.
http://documentation.ning.com/ says: "We're taking a short break" for a long time.

[David]

The 'ning' object does not yet exist -- it will be added in the near future. See http://developer.ning.com/forum/topic/show?id=1185512%3ATopic%3A132782 for details.

[Nathan Finstein]

The below snippet of code seems to work in the browser. And, when using makeRequest to call another server, "opensocial_viewer_id" param is absent when viewer is not signed in. But I don't see that either "opensocial_viewer_id" or "_anonymous" are documented. Can someone from Ning say whether we should be relying on these?

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req.add(req.newFetchPersonRequest(opensocial.IdSpec.PersonId.VIEWER),"viewer");
req.send(getViewer); }

function getViewer(resp) {
if (resp.get("viewer").getData().getId() == "_anonymous") { alert("viewer is not signed in"); }
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