bug 48541 - critical for PHP 5.3 View as Markdown

Hi Greg,

I can do it if someone can answer this question: how do closures
uniquely identify themselves? spl_autoload_register is mistakenly
treating all closures as if they were a single copy of the static method
"Closure::__invoke", and so only the first registered closure is ever
called (plus it leaks the other closures at shutdown). If the system
can be made to better identify the closure, then spl_autoload_register
can use that (and also properly free the refcount on a dupe).

A closure can only be uniquely identified by the object storage id the
object has. You cannot assume any identity with regard to, for example,
file name and line where it was defined, since one could imagine the
following:

foreach ($dirs as $dir) {
spl_autoload_register (function ($class) use ($dir) {
include $dir.'/'.$class.'.php';
});
}

(or something like it)

If nobody else does it I'll fix this later today.

Regards,
Christian

Christian Seiler wrote:

Hi Greg,

(I meant commit when I said patch, sorry :)

http://news.php.net/php.cvs/58696
and
http://news.php.net/php.cvs/58697

Thanks, looks fine to me. However, I noticed that closures don't work
with spl_autoload_unregister() and spl_autoload_functions(). Also,
classes that define __invoke work with spl_autoload_functions() but not
with spl_autoload_unregister() - unless array ($o, '__invoke') is given
to spl_autoload_register() directly, then the same will work for unregister.

Hi,

I first replied off-list accidentally. I wonder if the problem is that
spl_autoload_register should not just be checking to see if zcallable is
IS_OBJECT, but also if it is an instance of Closure. That should clear
up the examples below (spl_autoload_register($blah) where $blah is not a
closure should not work). spl_autoload_unregister probably just needs a
cut/paste of the code I committed to spl_autoload_register for munging a
closure name with the addition of Closure instanceof check.

Also, those examples would make great .phpt tests :).

Greg

Or, to sum it up:

i) Real Closures

$c = function ($class) { var_dump ('foo'); }
spl_autoload_register ($c);

var_dump (spl_autoload_functions ()); // '{closure}'

spl_autoload_unregister ($c); // no effect

ii) Invokables

WORKS:

<?php

class Autoloader {
private $dir;
public function __construct ($dir) {
$this->dir = $dir;
}
public function __invoke ($class) {
var_dump ("{$this->dir}/$class.php");
}
}

$al1 = new Autoloader ('d1');
$al2 = new Autoloader ('d2');

spl_autoload_register (array ($al1, '__invoke'));
spl_autoload_register (array ($al2, '__invoke'));

var_dump (spl_autoload_functions ());

spl_autoload_unregister (array ($al1, '__invoke'));

$x = new Test;

?>

SEMI-WORKS:

<?php

class Autoloader {
private $dir;
public function __construct ($dir) {
$this->dir = $dir;
}
public function __invoke ($class) {
var_dump ("{$this->dir}/$class.php");
}
}

$al1 = new Autoloader ('d1');
$al2 = new Autoloader ('d2');

spl_autoload_register ($al1);
spl_autoload_register ($al2);

var_dump (spl_autoload_functions ());
// gives array ($object, '__invoke') instead of
// directly $object - but that's at least equivalent

spl_autoload_unregister ($al1);
// no effect
spl_autoload_unregister (array ($al1, '__invoke'));
// no effect

$x = new Test;

?>

Regards,
Christian