--TEST-- Using isset() with arrays --FILE-- true, "a" => true, ]; var_dump(isset($array[0])); var_dump(isset($array["a"])); var_dump(isset($array[false])); var_dump(isset($array[0.6])); var_dump(isset($array[true])); var_dump(isset($array[null])); var_dump(isset($array[STDIN])); try { isset($array[[]]); } catch (TypeError $exception) { echo $exception->getMessage() . "\n"; } try { isset($array[new stdClass()]); } catch (TypeError $exception) { echo $exception->getMessage() . "\n"; } ?> --EXPECTF-- bool(true) bool(true) bool(true) Deprecated: Implicit conversion from float 0.6 to int loses precision in %s on line %d bool(true) bool(false) bool(false) Warning: Resource ID#%d used as offset, casting to integer (%d) in %s on line %d bool(false) Illegal offset type in isset or empty Illegal offset type in isset or empty