What is the form of Templated Friend Class Variable another Templated Class?

[b975]

AIterator ->Template Class
ASet ->Template Class

in the ASet.h(public section)(And AIterator.h included in ASet.h)
friend class AIterator<T>;

template<class T>
AIterator<T>::AIterator(ASet& friendVar)
{
	otherPtr = friendVar.sp;//sp is from protected section in ASet Class
}

What is the implementation of template class variable assigning another template class variable(which is friend class)?

[JLBorges]

Assuming that AIterator is the iterator class for ASet, this is what I would recommend:
make the iterator of ASet a member class of ASet. Then no special friend relationship would be required.

Something like:

template < typename T > struct ASet
{
    // ...


    struct AIterator // AIterator is a member of ASet<T>
    {
         AIterator( ASet<T>& set ) ;

         // ...

         T* other_ptr ;
    };

    AIterator begin() { return AIterator(*this) ; }

    // ...

    protected: T* sp = nullptr ;

};

template < typename T >
ASet<T>::AIterator::AIterator( ASet<T>& set ) : other_ptr( set.sp ) {}

If that is not the case, see: https://isocpp.org/wiki/faq/templates#template-friends

[sm2345110]

-1
down vote
In my case this solution works correctly:

template <typename T>
class DerivedClass1 : public BaseClass1 {
template<class T> friend class DerivedClass2;
private:
int a;
};

template <typename T>
class DerivedClass2 : public BaseClass1 {
void method() { this->i;}
};
I hope it will be helpful.
http://www.cetpainfotech.com/technology/c-language-training