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<?php $a = new StdClass(); $b = &$a; var_dump(is_ref($a, $b)); function is_ref(&$a, &$b) { // create a unique different value $differentValue = ($a === true) ? false : true; // We need a copy of $a, to keep safe. Note that if $a is a "referenced" value, $copy will be too. $copy = $a; // Change $a and check if $b changed too, finally restore $a using $copy. $a = $differentValue; $same = $a === $b; $a = $copy; return $same; }

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40.48 ms | 402 KiB | 5 Q