class Config extends \ArrayObject {
	// ...
	protected $fullPath = NULL;
	protected $store = [];
	public function __construct ($fullPath, $data) {
		$this->fullPath = $fullPath;
		$this->store = $data;
	}
	
	public function __get ($key) {
		if (array_key_exists($key, $this->store))
			return $this->store[$key];
		return NULL;
	}
	public function __set ($key, $value) {
		return $this->store[$key] = $value;
	}
	public function __isset ($key) {
		return isset($this->store[$key]);
	}
	public function __unset ($key) {
		if (isset($this->store[$key])) 
			unset($this->store[$key]);
	}
	public function getIterator () {
		return new \ArrayIterator($this->store);
	}
	public function offsetSet ($offset, $value) {
		if ($offset === NULL) {
			$this->store[] = $value;
		} else {
			$this->store[$offset] = $value;
		}
	}
	public function offsetGet ($offset) {
		return isset($this->store[$offset]) 
			? $this->store[$offset] 
			: NULL;
	}
	public function offsetExists ($offset) {
		return isset($this->store[$offset]);
	}
	public function offsetUnset ($offset) {
		unset($this->store[$offset]);
	}
	public function count () {
		return count($this->store);
	}
}


// let's create and instanceof class `Config`:
$cfg = new Config(__DIR__ . '/cfg.ini', [
	'ga' => true,
	'db' => [
		'driver'=> 'mysql',
		'host'	=> 'localhost',
		'port'	=> 3306,
		'db'	=> 'cdcol',
		'pass'	=> NULL
	]
]);

echo '<pre>';

// working ok in loops and other:
$cfg['something'] = 'more';
dump(count($cfg));
dump(isset($cfg['ga']));
dump(isset($cfg['something']));
unset($cfg['something']);
dump(isset($cfg['something']));
foreach ($cfg as $key => $value) {
	dump([$key, $value]);
}

// Working OK to dump it by simple `var_dump()`:
//var_dump($cfg);

// but it's not possible to dump with tracy:
dump($cfg);
bdump($cfg);

	//////////////// FIXED - return type `iterable` (PHP >= 7.1):
	//private function exportObject($obj): array
	private function exportObject($obj): iterable
	{
		foreach ($this->objectDumpers as $type => $dumper) {
			if (!$type || $obj instanceof $type) {
				return $dumper($obj);
			}
		}

		if ($this->debugInfo && method_exists($obj, '__debugInfo')) {
			return $obj->__debugInfo();
		}
		
		//////////////// ADDED - condition:
		if ($obj instanceof \ArrayObject) return $obj;
		
		return (array) $obj;
	}