stack template doesn't compile push func

I wrote this something-like-stack data structure:

template<class T>
class Stos {
    class Element {
        public:
        T n开发者_JS百科;
        Element* prev;
        Element(const T& k = 0): n(k), prev(0) {}
    };
    Element* member;
    Stos(Stos&);
    public:
    Stos(const T&);
    ~Stos();
    unsigned int count;
    T get();
    Element* push(const T&);
    T pop();
    void mod(const T&);
};

And implementation (same file):

template<class T>
Stos<T>::Stos(const T& n = 0): count(1) {
    member = new Element(n);
}

template<class T>
T Stos<T>::get() {
    return member->n;
}

template<class T>
Stos<T>::Element* Stos<T>::push(const T& n = 0) {
    Element* point = member;
    member = new Element;
    member->prev = point;
    if(n != 0) member->n = n;
    ++count;
    return member;
}

template<class T>
T Stos<T>::pop() {
    Element* point = member;
    T n = point->n;
    member = point->prev;
    --count;
    delete point;
    return n;
}

template<class T>
void Stos<T>::mod(const T& n) {
    member->n = n;
}

template<class T>
Stos<T>::~Stos() {
    while(member) pop();
}

And when I try to compile it with g++, I get this error about the first line of definition of Stos::Element* Stos::push(): expected constructor, destructor, or type conversion before ‘*’ token. It is my first try to write something with templates. This stack code did work without templates, when I'd edited it, then I got the error, everything worked just fine before with "int" everywhere instead of "T".

And I can't find out why it doesn't compile. Can't I use pointer to class::member?

You need to prefix the name Element with typename

typename Stos<T>::Element* Stos<T>::push(const T& n = 0) 

Here's a link to a full explanation of why this is necessary

• http://pages.cs.wisc.edu/~driscoll/typename.html

You should also consider using

const T &n = T()

instead of

const T &n = 0

Since not all possible T may be able to be initialized from 0!