note 124708 deleted from language.variables.scope by crell

From: Date: Thu, 31 Mar 2022 19:35:12 +0000
Subject: note 124708 deleted from language.variables.scope by crell
References: 1  Groups: php.notes 
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Note Submitter: iphstich at gmail dot com ---- It seems that static variables defined within a class method or static function are stored separately for the class and each extended class of it. It's sort of like, every time you extend a class, functions with static variables are re-writen, and the static variable re-created. Even if the function is defined as final! <?php class A { function x () { static $x = 0; return ++$x; } static function y () { static $y = 0; return ++$y; } final static function z () { static $z = 0; return ++$z; } } class B extends A { } class C extends B { } // As methods, A and B have different values for x $a = new A(); echo $a->x(); // 1 $b = new B(); echo $b->x(); // 1 echo $b->x(); // 2 // And different instances of C will have the same values for x $c1 = new C(); $c2 = new C(); $c3 = new C(); echo $c1->x(); // 1 echo $c2->x(); // 2 echo $c3->x(); // 3 // The same behavior applies to static functions echo A::y(); // 1 echo B::y(); // 1 echo B::y(); // 2 echo C::y(); // 1 echo C::y(); // 2 echo C::y(); // 3 // The same behavior still applies to FINAL static functions echo A::z(); // 1 echo B::z(); // 1 echo B::z(); // 2 echo C::z(); // 1 echo C::z(); // 2 echo C::z(); // 3 ?> Tested with version 7.0.13

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