C：不访问嵌套类的Friend方法

using namespace std;

template<class T> class olsm;                 
template<class T> istream& operator>>(istream& in,olsm<T>& x);
template<class T> ostream& operator<<(ostream& out,olsm<T>& x);

template <class T>                                              
class olsm {

    friend istream& operator>> <> (istream& in,olsm& x);
    friend ostream& operator<< <> (ostream& out,olsm& x);

    public:                                
        class node {                           
            public:
        };

        ///Other stuff
};      

////More stuff

template<class T>
ostream& operator<<(ostream& out,olsm<T>& x) {

    olsm<T>::node* rowNode = x;

    //Even more stuff!

    return out;
}

但是当我尝试编译时,我得到了,

error: 'rowNode' was not declared in this scope

这是奇怪的,因为我在线路上得到了错误,我试图宣布它.有谁知道为什么？