While this file is useful for debugging, it requires metatype to be present. If this module is not loaded, there is an error. Please either document it at the head of the module, or adjust anywhere that requires on the MetaType function. The adjustment for rs2html is
if (method_exists($rs, 'MetaType')) $typearr[$i] = $rs->MetaType($field->type,$field->max_length);
else $typearr[$i] = '?'; // default to an undefined meta type.