Question

I had that weird thing using arrays in PHP.

$items = array();
$tools = json_decode($_GET['tools'],true);
foreach($tools as $key => $value)
{
   $items[$somevar][$anothervar] = $value;
}

Then I could iterate $items

foreach($items as $key => $value)
{
  //Do Something
}

But the weird part is, when I tried again to iterate through $tools with foreach, it returns NULL.

//Never Happens    
foreach($tools as $key => $value)
{
  //Do Something
}

Could this be caused by the Garbage Collector?

My app is running with PHP 5.2.3, Linux CentOS, Apache 2.2.

Answer 1

No, I doubt that this has to do with the garbage collection.

The garbage collector only removes a zval (a PHP variable container) if the refcount is zero. This means, only if no variable-reference points to the data, it will get removed.

As long as you don’t do an unset( $tools );, the variable should be available.

See http://php.net/features.gc.refcounting-basics.php for details.