I have a template class that is designed to contain built in types or std::string types. I always need to be able to cast an instance of the class as a std::string, and I also need to be able to cast it as the parameter type with which it was instantiated. In my class definition, I have defined two cast operators, like so: (Extraneous stuff omitted) template<typename T> class MyDataObject : public MyDataObjectBase { // Cast as std::string inline operator const std::string & () { ...some code here } // Cast as T inline operator const T & () { ...some code here } } The original code was written on a Mac and compiled with Gnu, which did not complain. even when I did this: class MyStringObjectClass : public MyDataObjectstd::string { } Now, however, I have moved the code to Windows, and the Visual Studio compiler complains about the second cast operator when I define MyStringObjectClass. I thought that if I could conditionally define the cast as T operator (or the cast as std::string) I would be okay, but that means testing against the value of T with the preprocessor. I don't see how to do that, but I know that some of you folks are really good at bending the preprocessor to your will. Can anyone show me a way out of this predicament? Thanks, Rush