Question

I am trying to avoid LOKI_TYPELIST_n macros, so I though I can write simple Loki::Typelist wrapper.

template <typename...Ts>
struct TYPELIST;

template <>
struct TYPELIST<>
{
    typedef Loki::NullType Result;
};

template <typename HEAD, typename...Ts>
struct TYPELIST<HEAD,Ts...>
{
    typedef Loki::Typelist<HEAD, TYPELIST<Ts...>::Result> Result;
};

Upon compilation I get the following error:

error: type/value mismatch at argument 2 in template parameter list for ‘template<class T, class U> struct Loki::Typelist’
error:   expected a type, got ‘TYPELIST<Ts ...>::Result’

I though TYPELIST<Ts...>::Result is a type. What is wrong with it?
GCC 4.6.2 here.

I want to use it like this:

typedef TYPELIST<
        EventTank1,
        EventTank2,
        EventTank3
    >::Result EVENTS_ALL__;

Thank you.

Answer 1

You forgot the typename word in front of TYPELIST<Ts ...>::Result. Just because you know it is a type does not mean that the compiler knows it too (if only!).