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<?php class A { private static $instance; public static function getInstance() { if (null === $this->instance) { static::$instance = new self; } return static::instance; } } $a = A::getInstance(); var_dump($a);
Output for 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Fatal error: Uncaught Error: Using $this when not in object context in /in/o3MlE:9 Stack trace: #0 /in/o3MlE(17): A::getInstance() #1 {main} thrown in /in/o3MlE on line 9
Process exited with code 255.
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.40
Fatal error: Using $this when not in object context in /in/o3MlE on line 9
Process exited with code 255.

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