Re: nested templates and partial specialization

On 11/12/2011 12:33 PM, ld wrote:


Heh, it is much simpler: there is a subtle difference between
template<class T>
and
template<typename T>

The second one does not match B<T>, while the first one does. The
code below works too.

Edek

// type declaration
template <typename T, typename I>
struct E; // line 3

// abstract class
struct D {
   virtual void doit() const = 0;
};

// partial specialization
template <class T>
struct E<T, D> {
   virtual void doit() const;

   explicit E(T = T());
   T& e;
};

// simple class
struct A {
   void doit() const;
   int a;
};

// template class
template <typename T>
struct B {
   void doit() const;
   T b;
};

// specialization with class, ok
template <>
void
E<A, D>::doit() const
{
   e.doit();
}

// specialization with template class, error NO ERROR NOW
template <class T>
void E<T, D>::doit() const // line 43
{
   e.doit();
}

int main() {
   E<A, D> a;
   E<B<int>, D> b;
}