Comparing the PHP 7 and Hack Type Systems(dmiller.io) |
Comparing the PHP 7 and Hack Type Systems(dmiller.io) |
Fatal error: Argument 1 passed to myLog() must be of the type string, integer given, called in /home/vagrant/basic/main.php on line 9 and defined in /home/vagrant/basic/main.php on line 4
Hrm, PHP is telling you both line 4 and line 9, as where the function is defined and where it's being called with bad data, which is quite nice. In comparison, HHVM is saying line 6, which is a closing brace for the myLog function. In my books, PHP's approach is way way better then HHVM's
After writing a couple small programs in Hack I've realized that it's not types themselves that make writing Hack enjoyable: it's the tight feedback loop Hack creates between the machine and myself. Integrating the Hack type checker into my editor means that my entire codebase is analyzed in a split second as soon as I save a file. This immediately surfaces any dumb, or subtle mistakes I made. I find myself writing code fearlessly: when I forget what a function returns, I just write code that calls it with what I think it returns. If I'm wrong, the type checker will tell me immediately. I can fix it quickly, and move on.
Hack's type system is static -- it's enforced by a static analysis tool that instantly reports errors in all of your code. PHP can only report errors that it actually encounters at runtime. Along with the "fearlessness" above, it also means that you might miss you forgot to check for a null in an error case... until it explodes at runtime in production. Hack's static type system can mechanically check for all of these immediately.
Of course, a tool for PHP 7 can only go so far, because PHP 7's type hints aren't sufficient to cover everything, unlike Hack which has things like nullable support.
declare(strict_types=1)
function dowork(@?string $w)
XHP has allowed me to do the same, by forcing me to write well formed html and I love it
Maybe you should try it?
It was a "catchable" fatal error (i.e. E_RECOVERABLE_ERROR) in PHP 5.x for typehints. But PHP 7 is changing it to be an Exception instead, and for some reason it currently produces an inaccurate error message in the master branch - it should say "Uncaught exception" (which it is), but that's not been fixed yet. Trunk builds aren't ready for production use, etc.
https://github.com/php/php-src/pull/1045 https://wiki.php.net/rfc/nullable_types
not for 7.0 but hopefully for 7.1
Nevertheless, congrats to them, they actually deliver.
People has recently become quite reluctant to 'hate' on php, as if it is some kind of deformed being who needs emotional support. It is like criticizing Christopher Nolan.
You just don't 'hate' on it with out sliding in a few praises. I know that criticizing the language will result in heated (often irritating) debate with the php fan boys (I call them fan boys because other php users will not come justify the language, with things like, "every language has faults so it is ok"). But I think we can use a little less sugar coating. I am not telling that the language should be killed right off, but please just don't romanticize it's faults and send people who are serious about programming down a path they have to (hopefully) come back 9 or 10 years later (When they are finally disillusioned).
EDIT: he..he..downvotes!
declare(strict_typehints=TRUE);
This mindset is something that I've personally seen uniquely permeate every layer of the PHP community, more than anywhere else. I'm honestly curious, what makes communities seem to value things like typing less characters over clarity and correctness? The most important thing to me is reducing the amount of mental state needed for a human to read any line of code.
declare(types=strict);
declare(strict_typehints=TRUE); // not ironic, not short
declare(strict_types=1); // ironic, short
declare(strict=true); // not ironic, even shorter
Also the declare syntax could've been augmented to support passing implicit boolean parameters without setting a value:
declare(strict); // oh yeah.
The language itself feels like a bag of features copied over from top contenders from the TIOBE index. You can see the fastness in the core of the language design.
After all, you use PHP to perform MySQL queries in the middle of HTML tags. If you want to do this, you know some principles are merely burden for your smooth execution of the web site development, and should be throw out the window at first thought.
The sort of approach you're describing is not suggested or used by anyone with half a clue what they're doing.
Well, it could've been this:
declare(types="strict");
For some reason, this Easter egg was deemed too important to displace with an actual language construct.
<?hh // strict