Reference Guide

facebook FBML Reference Guide Page 77 of 159

Cache Expiration

As mentioned within a forum thread by a member of the Facebook team: "You only need to publish on update.

We'll keep it otherwise."

So the cache never expires and you will not need to periodically update your application cache. Facebook will

keep the cache indefinitely. However, developers should not rely on the cache always keeping their data – i.e. it

is not safe to assume that once data has been cached (in the case of a URL ref), it can be deleted from your

server.

Nested Refs

The contents of a ref handle can contain FBML, including other <fb:ref> tags.

Warning: An infinite nesting can be created by creating two ref handles that refer to each other. Do not do this.

FBML Anomalies in Refs

Some FBML tags do not currently appear to operate as expected when nested inside a ref handle.

[possible bug?]

These include: <fb:if-is-own-profile>.

[verify]

- (RobRoy) I can use <fb:if-is-own-profile> inside a ref handle just fine. Anyone else still experiencing this?

This writer has not been able to successfully create mock-Ajax forms inside of ref handles

[possible bug?]

(but that

does not necessarily mean they don't work).