code: private static boolean isNamed(String funcName, Argument[] args) throws TransformerException {
  	if (ArrayUtil.isEmpty(args)) return false;
  	boolean named = false;
  	for (int i = 0; i < args.length; i++) {
  	    if (args[i] instanceof NamedArgument) named = true;
  	    else if (named) throw new TransformerException("invalid argument for function " + funcName + ", you can not mix named and unnamed arguments", args[i].getStart());
  	}
  
  	return named;
      }
docs: check if the arguments are named arguments or regular arguments, throws a exception when mixed
  
  @param funcName
  @param args
  @param line
  @return
  @throws TransformerException