Could anyone explain differences between error_reporting(E_ALL); and error_reporting(E_ALL & ~E_NOTICE); ?
I noticed that when I change from E_ALL to E_ALL & ~E_NOTICE, an error which I was hacking, disappears.
E_ALL is "everything"
E_ALL & ~E_NOTICE is "everything except notices"
Notices are the least-urgent kinds of messages. But they can be very useful for catching stupid programmer mistakes, like trying to read from a hash with a non-existent key, etc.
(To understand the syntax, read up on bitwise operators)