public function __clone()
{
$this->fqsen_class_map = clone $this->fqsen_class_map;
$this->fqsen_global_constant_map = clone $this->fqsen_global_constant_map;
$this->fqsen_func_map = clone $this->fqsen_func_map;
$this->class_fqsen_class_map_map = clone $this->class_fqsen_class_map_map;
$this->func_and_method_set = clone $this->func_and_method_set;
}