How to use reinterpret cast for inner template class?

Question

I have two template classes as outer and inner. I am type casting to inner class from other inner class object. I am getting compilation error. How to resolve this?

template<typename O>
struct outer
{
   template<typename I>
      struct inner
      {
      };

   inner<int> *ptr;
   outer();

};

   template<typename O,typename I>
void callme()
{
   reinterpret_cast< outer<O>::inner<I> *>(NULL);
}

Kerrek SB · Accepted Answer · 2017-05-03T14:49:41.587

4

You want:

reinterpret_cast<typename outer<O>::template inner<I> *>(nullptr);
//               ^^^^^^^^           ^^^^^^^^             ^^^^^^^

The names outer and inner are dependent names (they depend on template arguments), and therefore you need to explicitly specify their "kind" (value, type, template).

edited May 03 '17 at 14:49

answered May 03 '17 at 14:37

Kerrek SB

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Great. Why we need to put template in 'template inner'? – VINOTH ENERGETIC May 03 '17 at 14:39
1

Because `inner` is a dependent name, and so you need to disambiguate its kind. – Kerrek SB May 03 '17 at 14:41

How to use reinterpret cast for inner template class?

1 Answers1