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<?php $isset = true; $array = array(); $notSetArray = array(0=>''); $string = ''; // Test Source function Test9_2() { global $isset; /* The Test */ $t = microtime(true); while($i < 2000) { empty($isset); ++$i; } return (microtime(true) - $t); } // Variable Clean-up function Test9_End() { global $isset, $array, $string; unset($isset, $array, $string); }
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.21, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.17 - 7.2.25, 7.3.0 - 7.3.12, 7.4.0

preferences:
135.45 ms | 404 KiB | 204 Q