C++ keywords: typename

From Cppreference

[edit] Usage

• In a template declaration used to declare templated types
• Inside a template definition, to declare that a static member of a class depending on a template is a type

[edit] Example

template <typename T>
    void foo ( const std::vector<T>& v )
    {
        typename std::vector<T>::const_iterator it = v.begin();
    }