[vtkusers] Cross Delegation with vtkSQLDatabase

[Matthew Green]

Hi guys,

I'm wanting to do something similar to this. I'm guessing part of the
reason why I can't is because vtkSQLiteDatabase, vtkMySQLDatabase etc
etc don't virtually inherit vtkSQLDatabase?

----------
#include "vtkSQLDatabase.h"
#include "vtkSQLiteDatabase.h"
#include "vtkMySQLDatabase.h"

class mySQLDatabase : public virtual vtkSQLDatabase
{
        bool foo()
        {
                //do foo
                return true;
        }
};

class mySQLiteDatabase : public vtkSQLiteDatabase, public mySQLDatabase
{
};

class myMySQLDatabase : public vtkMySQLDatabase, public mySQLDatabase
{
};

int main()
{
        mySQLiteDatabase database();
        database.foo();
}
----------

Is this something VTK should try to accommodate? Or is there already a
way of doing this?