Templated Base Classes

Yes, but not necessarily in the same form:

template < typename T >
BaseClass
{
protected:
  T * t_ptr;
  T t_instance;
};
...
// note that DerivedClass is not necessarily a template
class DerivedClass : public BaseClass< int >
{
// class inherits t_ptr as int * and t_instance as int
}; 

Obviously, if the type used to instantiate BaseClass is a concrete type for which no default constructor exists, DerivedClass will fail to compile.

Let me rephrase that

A class can only inherit from a fully instanciated template.

Whether to derive from a ''fixed'' specialisation
- class Derived : public Parent<int, double> {};

or to leave that control to a template parameter of the derived class

- template <class T, class U> class Derived : public Parent<T, U> {};

or to mix and match

- template <class T> class Derived : public Parent<T, double> {}; *

is entirely up to you.

* This is not partial template specialisation.

Documents [ GDNet | MSDN | STL | OpenGL | Formats | RTFM | Asking Smart Questions ]
C++ Stuff [ MinGW | Loki | SDL | Boost. | STLport | FLTK | ACCU Recommended Books ]

Ahh I see, thanks.


Reality is Relative -Me and Probably somebody else