Facebook strange javascript that contains endless loop

Question

When I debugged my facebook apps, I found a strange facebook javascript that contain an endless loop, but it has no body. What is the purpose of this for(;;); loop?

for (;;);{"__ar":1,"payload":{"content":[],"custom_stories":[],"newest":0}}

URL:https://apps.facebook.com/ajax/canvas_ticker.php?__a=1

Possible duplicate: http://stackoverflow.com/questions/3058401/empty-for-loop-in-facebook-ajax — jwheron, Nov 30 '11 at 16:53
It could be a way of preventing the text returned from being `eval`-ed. It would need to be parsed. — meouw, Nov 30 '11 at 16:54
I had to read the answer on that question a few times before it made sense to me. Hopefully it helps. — jwheron, Nov 30 '11 at 16:55
@jwiscarson I don't get the point :-? It's hard for me to understand :-s — hungneox, Nov 30 '11 at 16:58

score 0 · Accepted Answer · answered Nov 30 '11 at 17:06

0

Although I linked to a duplicate, the answer on that question is difficult to understand. To the best of my understanding, it means:

Facebook does not want you to directly use the results from their AJAX directly. They want you to go through their API. They don't want you to include their scripts, make use of their internal AJAX responses, and then have direct access to the data returned from those responses.

answered Nov 30 '11 at 17:06

jwheron

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but how a endless loop prevent me to make use of their internal AJAX? – hungneox Nov 30 '11 at 17:14
An endless loop will never return data to you. – jwheron Nov 30 '11 at 17:31

Facebook strange javascript that contains endless loop

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