anchor.diff:     {
   		$again = (_input.LT(1).getType() == IP || _input.LT(1).getType() == IPV6) &&
   		_input.LT(2).getType() == PREFIX_LIST &&
  -		_input.LT(3).getType() == VARIABLE &&
  +		_input.LT(3).getType() != NEWLINE &&
   		_input.LT(3).getText().equals($name.text);
   	}
   
  
positive.code:    (
        IP
        | IPV6
     ) PREFIX_LIST name = ~NEWLINE NEWLINE ip_prefix_list_tail*
  ;
  
  null_as_path_regex
  
negative.code:    (
        IP
        | IPV6
     ) PREFIX_LIST name = ~NEWLINE
     (
        ip_prefix_list_tail
        | ip_prefix_list_null_tail
  