Interfacing to C++ / Fltk

[Michael]

Hi,

I have C++ code:
-----
#define dllExport __declspec(dllexport)

namespace fltk = fltk3;

class dllExport FltkWindow : public fltk::Window
{
        public:
			FltkWindow(int w, int h, const char* title = 
nullptr):fltk::Window(w, h, title) { }

};



dllExport FltkWindow* get_Win(int w, int h, const char * title = 
nullptr)
{
        FltkWindow * win = new FltkWindow(w, h, title);

        if(win)
        {
                cout<<"not null win";
                return win;
        }

        cout<<"null win";
        return 0;
};
-----

And D code:

-----
extern (C++)
{
        interface FltkWindow
        {
                void show();
        }

        FltkWindow get_Win(int, int, const char*);
}

class FliWindow
{
        private FltkWindow _win;

        public this(int w, int h, string label = "Fli_Window")
        {
                _win = get_Win(w, h, label.ptr);
                writeln(label);
        }

        public void ShowMe(string[] args)
        {
                writeln("ShowMe");
                _win.show();

        }
}
-----
int main(string[] args)
{
    FliWindow w = new FliWindow(300, 200);
    w.ShowMe(args);
    return Fltk.Run();
}

-----
And output:
-----
Fli_Window
ShowMe
not null win
-----

Why not "not null win -> Fli_Window -> ShowMe"?

P.S.: Win 7 64bit, Dmd 2.060, Dmc 8.52, Fltk 3.0.