Thread: friend function template class declaration error

You haven't probably forward declared the function.

Code:

//uncomment to fix
/*
template <class T>
class X;

template <class T>
X<T> operator/(const T div, const X<T>& v);
*/
template <class T>
class X
{
    friend X<T> operator/<>(const T div, const X<T>& v);
};

int main()
{
    X<int> x;
    10 / x;
}

//implementation
template <class T>
X<T> operator/(const T , const X<T>& ) { return X<T>(); }

I don't entirely understand your use of extra brackets and the scope operator (they just change the wording of the error message).

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