I'm reading the C++ Template Metaprogramming book and I'm not understanding the following code from page 65-66: template <class T> struct param_type : mpl::eval_if < typename boost::is_scalar<T>::type , mpl::indentity<T> , boost::add_reference<T const>
{}; template <class T> struct param_type : mpl::eval_if < boost::is_scalar<T> --> ^^^^^^^^^^^^^^^^^^^^^^^ <-- , mpl::indentity<T> , boost::add_reference<T const>
{}; After reading again and again the explanation I still don't get why we don't need to use typename ....::type anymore. The text explains that all Boost's integral metafunctions suply a nested ::value, but how it is used in this context ? Any help would be greatly appreciated. Best regards, Eduardo