protected static function _diff($left, $right) {
		$result = [];

		foreach ($left as $key => $value) {
			if (!array_key_exists($key, $right) || $left[$key] !== $right[$key]) {
				$result[$key] = $value;
			}
		}
		return $result;
	}
protected static function _diff($left, $right) {
		$result = [];

		foreach ($left as $key => $value) {
			if (!array_key_exists($key, $right) || $left[$key] !== $right[$key]) {
				$result[$key] = $value;
			}
		}
		return $result;
	}
protected static function _diff ( $ left , $ right ) { $ result = [ ] ; foreach ( $ left as $ key => $ value ) { if ( ! array_key_exists ( $ key , $ right ) || $ left [ $ key ] !== $ right [ $ key ] ) { $ result [ $ key ] = $ value ; } } return $ result ; }
Handle diffing operations between `Document` object states. Implemented because all of PHP's
array comparison functions are broken when working with objects.

@param array $left The left-hand comparison array.
@param array $right The right-hand comparison array.
@return array Returns an array of the differences of `$left` compared to `$right`.
Handle diffing operations between Document object states . Implemented because all of PHP s array comparison functions are broken when working with objects .