code: protected void reportWrongNumberArgs() throws WrongNumberArgsException {
      String fMsg = XSLMessages.createXPATHMessage(
          XPATHErrorResources.ER_INCORRECT_PROGRAMMER_ASSERTION,
          new Object[]{ "Programmer's assertion:  the method FunctionMultiArgs.reportWrongNumberArgs() should never be called." });
  
      throw new RuntimeException(fMsg);
    }
docs: Constructs and throws a WrongNumberArgException with the appropriate
  message for this function object.  This class supports an arbitrary
  number of arguments, so this method must never be called.
  
  @throws WrongNumberArgsException