Simple access array with ->
notation.
$arrow = new Arrow(['something' => 1]);
echo $arror->something;
Output:
1
$arrow = new Arrow(['something' => 1], true);
echo $arror->something->otherthing;
Output:
''
$arrow = new Arrow(['something' => 1], true);
var_dump($arror->something());
Output:
int(1)