Debug C ++ Custom Type Renderer for Visual Studio

I am working with a library with some awkward types. When debugging in Visual Studio, I would like to display them in a readable form. I found some helpful articles on how to edit the autoexp.dat file.

http://www.idigitalhouse.com/Blog/?p=83

or

http://mariusbancila.ro/blog/2007/04/06/tweaking-autoexpdat-for-custom-types-in-vs2005/

Suppose I have a String class:

class String {
//...
private:
    char *_cbuf;
}

      

        
        
        
      

    

then I can easily add a renderer because _cbuf is a member variable. I'm just writing

String{
preview (
[$c._cbuf]
)
}

      

        
        
        
      

    

at the beginning of the section [Visualizer]

in the autoexp.dat file and it works.

But suppose I want to map a more complex type that has no useful member variables, but has very useful methods. For example:.

class Date {
    //...
    String asString() const;
private:
    long _someReallyStrangeAndUnusefulDateRepresentation;
}

      

        
        
        
      

    

And I want to display a string, not a long one. How to do it? Recording

Date{
preview (
[$c.asString()]
)
}

      

        
        
        
      

    

in autoexp.dat doesn't work.