Correct syntax of making a "class template" friend to a class [closed]

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Closed 9 years ago.

I just need:

Correct syntax of making a "class template" friend to a class

Answer 1

Given a class template, for example

template <typename> class Template;

you can either befriend a particular specialisation of the template:

friend class Template<int>;

or all specialisations:

template <typename> friend class Template;

Answer 2

If you want a different typed friend class:

template<typename,typename> friend class ClassName;

Answer 3

In C++11 you can do this:

template<typename T>
class C
{
    friend T;
};