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run code in 150+ php & hhvm versions
Bugs & Features
<?php function countRefs($var) { ob_start(); debug_zval_dump($var); preg_match('~refcount\((\d+)\)~', ob_get_clean(), $matches); return $matches[1] - 4; } $a = 0; $a = &$a; echo countRefs($a); $a = &$a; echo countRefs($a);
Output for 7.0.0 - 7.1.0
Notice: Undefined offset: 1 in /in/tTXJf on line 7 -4 Notice: Undefined offset: 1 in /in/tTXJf on line 7 -4
Output for hhvm-3.10.0 - 3.12.0
-3-3
Output for 4.3.0 - 5.6.28
-1-1