trouble with nested class within class template

[nuderobmonkey]

How can I declare and define an inner class within a class template?

Without template I got it to work:

//==== declarations
struct Outer {
    struct Inner;
    Inner fnc_outer();
};
struct Outer::Inner {
    void fnc_inner();
};


//=== definitions:
Outer::Inner Outer::fnc_outer() { return Inner(); }
void Outer::Inner::fnc_inner() { /* do something */ }


int main()
{
    Outer o;
    o.fnc_outer().fnc_inner();
}
// This works fine. 

But how do I nest the inner class into a class template?
This doesn't work:

//=== declarations
template <typename T>
struct Outer {
    struct Inner;
    Inner fnc_outer();
};
template <typename T>
struct Outer<T>::Inner {
    void fnc_inner();
};

//=== definitions:
template <typename T>
Outer<T>::Inner Outer<T>::fnc_outer() { return Inner(); }

template <typename T>
void Outer<T>::Inner::fnc_inner() { /* do something */ }


int main()
{
    Outer<int> o;
    o.fnc_outer().fnc_inner();
}

// What's wrong with this example? 

Here i get this error message:

14:1: error: missing 'typename' prior to dependent type name
      'Outer<T>::Inner'
Outer<T>::Inner Outer<T>::fnc_outer() { return Inner(); }
^~~~~~~~~~~~~~~
typename 

What does it mean?

Thanks for help.

[Peter87]

As the compiler says, you need to use the typename keyword.

typename Outer<T>::Inner Outer<T>::fnc_outer() { return Inner(); }

[gunnerfunner]

See about dependent scopes here:
http://stackoverflow.com/questions/610245/where-and-why-do-i-have-to-put-the-template-and-typename-keywords

[nuderobmonkey]

Thank you both. The link was illustrative to me!