CODEWITHSUNDEEP
phphhvmhacklang
Jader Feijo
Jader Feijo

Reputation: 1209

Hack typechecker not recognising 'global' keyword inside a function

I'm using HHVM to write a system tool and I cannot for the life of me figure out why this code issues an error when I run hh_client

$__al_paths = array();

function requires(string $classPath): void {
    global $__al_paths;
    $className = basename($classPath);
    if (!isset($__al_paths[$className])) {
       $__al_paths[$className] = AL_CLASSES_FOLDER.'/'.$classPath.'.'.AL_CLASS_EXTENSION;
    }
}

This issues the following when I run hh_client

/usr/lib/mango/tools/autoloader.hh:9:9,19: Expected

The line it is pointing to is the line that says

global $__al_paths;

Which is being declared in the global scope. This appears to be a syntax error, it is as if the global keyword is not supported on HHVM, however I checked the documentation and it has several examples of it being using in Hack code.

Upvotes: 4

Views: 464

Answers (3)

Jader Feijo
Jader Feijo

Reputation: 1209

UPDATE !!!

This seemed to solve the problem, I'd like to know why the global keyword doesn't work though.

$__al_paths = array();

function requires(string $classPath): void {
    $__al_paths = $GLOBALS['__al_paths'];
    $className = basename($classPath);
    if (!isset($__al_paths[$className])) {
        $__al_paths[$className] = AL_CLASSES_FOLDER.'/'.$classPath.'.'.AL_CLASS_EXTENSION;
        $GLOBALS['__al_paths'] = $__al_paths;
    }
}

Upvotes: 0

Josh Watzman
Josh Watzman

Reputation: 7260

First, HHVM itself supports everything from the PHP language when you're writing PHP code, including global. This restriction is due to your usage of the Hack language -- global is one of the things that we removed from the language. If you really really need globals, you can use $GLOBALS in partial mode only, but strict mode disallows them altogether. (And if you see our documentation using global, it's wrong, please use the button on the page to file a bug!)

Upvotes: 4

TiMESPLiNTER
TiMESPLiNTER

Reputation: 5889

Instead of using global try to rewrite your code like this (called dependency injection):

function requires(string $classPath, $__al_paths): void {
    $className = basename($classPath);
    if (!isset($__al_paths[$className])) {
       $__al_paths[$className] = AL_CLASSES_FOLDER.'/'.$classPath.'.'.AL_CLASS_EXTENSION;
    }
}

Then call it like:

$__al_paths = array();

requires('classpath', $__al_paths);

This way you produce much more flexible and more stable code than playing around with globals which should been deleted from every humans mind.

Upvotes: 1

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