Having taken a look in the past, now it’s time to look into the future, namely 5.6 (PHP 7 is the future future, we’ll get there eventually). So I’d like to make some predictions of what would work well and not so well and then see if it would make sense in two years or turn out completely wrong.
I expect those things to be really helpful for people going to PHP 5.6:
Constant expressions – the fact that you could not define const FOO = BAR + 1; was annoying for some for a long time. Now that this is allowed I expect people to start using it with gusto.
Variadics – while one can argue variadics are not strictly necessary, as PHP can already accept variable number of args for every function, if you’re going to 5.6 the added value would be enough so you’d probably end up using them instead of func_get_args and friends.
Operator overloading for extensions – the fact that you can sum GMP numbers with + is great, and I think more extensions like this would show up. E.g., for business apps dealing with money ability to work with fractions without precision loss is a must, and right now one has to invent elaborate wrappers to handle it. Having an extension for this would be very nice. Finding a way to transition from integer to GMP when number becomes too big would be a great thing too.
Still not convinced having it in userspace is a great idea, what C++ did to it is kind of scary.
phpdbg – not having gdb for PHP was for a long time one of the major annoyances. I expect to use it a lot.
Function and constant importing – this was asked for a long time, but I still have hard time believing a lot of people would do it, since people who need imports usually are doing it in OO way anyway.
OpenSSL becoming strict with regard to peer verification by default may be a problem, especially for intranet apps running on self-signed certs. While this problem is easily fixable and the argument can be made that it should have been like this from the start – too many migrations go on very different paths depending on if it requires changing code/configs or not.
Adoption – again, with 5.5 adoption being still in single digits, I foresee a very slow adoption for 5.6. I don’t know a cure for “good enough” problem and I can understand people that do not want to move from something that already works, but look at the features! Look at the performance! I really hope people would move forward on this quicker.
While 5.4 will always have a special place in my heart, I hope people now staying on 5.2 and 5.3 would jump directly to 5.6 or at least 5.5. The BC delta in 5.5 and 5.6 is much smaller – I think 5.3->5.4 was the highest hurdle recently, and 5.4 to 5.5 or 5.6 should go much smoother.
Anything you like in PHP 5.6 and I forgot to mention? Anything that you foresee may be a problem for migration? Please add in comments.