Yesterday Facebook launched HipHop, a sourcecode-converter from php to c++. The set of php functions and constructions is more limited than in standard php.
Are the current popular php frameworks (ZF, CakePHP, symfony) compatible with HipHop? If not, which parts of these frameworks are not usable?
If I'm not mistaken, HipHop has not been released yet -- even the wiki page linked from the Facebook annoucement yesterday is not up yet.
So, it's going to be a bit hard to answer, right now.
I suppose it'll all depend on :
eval
is not supported by HipHop