must exist. Using these, the functions as well as parameter types and return values can be determined. As return values, the Double and String types are supported. As parameters, additionally the cell areas
。使用这些函数，可以确定函数以及参数类型和返回值。对于返回值，支持双精度和字符串类型。对于参数，也支持其他的单元格区域