Bug #16245 Updated: Static variables into class member funtions have wrong scope

ID: 16245 Updated by: hholzgra@php.net Reported By: flying@dom.natm.ru -Status: Open +Status: Bogus Bug Type: Documentation problem Operating System: Windows 2000 Server PHP Version: 4.0.6 New Comment: Thank you for taking the time to write to us, but this is not a bug. Please double-check the documentation available at http://www.php.net/manual/ and the instructions on how to report a bug at http://bugs.php.net/how-to-report.php Previous Comments: ------------------------------------------------------------------------ [2002-03-24 14:26:07] flying@dom.natm.ru > I guess this is expected behaviour. I can't agree with it. If there is two separate instances of a class - they must have no common variables, but they have. > Reclassified as a documentation problem. > (BTW you can use global $cnt to overcome this problem) No, problem can be solved by having member variable instead of static. ------------------------------------------------------------------------ [2002-03-24 14:22:08] sander@php.net I guess this is expected behaviour. Reclassified as a documentation problem. (BTW you can use global $cnt to overcome this problem) ------------------------------------------------------------------------ [2002-03-24 11:28:51] flying@dom.natm.ru Static variables inside member functions of a classes have wrong scope. They should belong to each instance of a class, like normal class properties, but they're belong to class definition instead and, therefore, shared between every instance of this class. It makes static variables unusable into class member variables. Here is an example: // Define class class A { var $id = null; function A($id) { $this->id = $id; } function func() { // Here we have counter into static variable static $cnt; if (!$cnt) $cnt = 0; // Show counter value and ID of a class instance echo $this->id.": ".($cnt++)."\n"; } }; // Create 2 instances of our class with different IDs $a = new A('A'); $b = new A('B'); // Call method of each class instance twice and see, // what will happen $a->func(); $b->func(); $a->func(); $b->func(); Expected results: ----------------- A: 0 B: 0 A: 1 B: 1 Actual results: --------------- A: 0 B: 1 A: 2 B: 3 ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=16245&edit=1