c++11 - Merge two variadic templates in one -


im trying implement variadic template wrapper of loki typelist.

merging 2 typelists in loki-style easy, im having problems merge in variadic-template style.

this implementation (simplified, without push_back , index_of , ... , methods).

template<typename... ts> struct dl32typelist;  template<typename head , typename... tail> struct dl32typelist<head,tail...> {     static const unsigned int size = sizeof...(tail) + 1;      using value = dl32loki_like_typelist<head, typename dl32typelist<tail...>::value>; };  template<> struct dl32typelist<> {     using value = dl32notype;      static const unsignedint size = 0; };

i want like:

template<typename other_typelist>  using merge = dl32typelist<head , tail... , typename other_typelist::???>;

and problem: cannot store variadic template args using/typedef, have idea how can this. (note other_typelist::???).

i don't know loki or dl32 are, , it's not clear should implementing @ all.

std::tuple common tool type lists. designed runtime storage container works compile-time utility long types complete. here 1 way catenate tuples:

template< typename ... t > struct tuple_cat     { typedef decltype( std::tuple_cat( std::declval< t >() ... ) ) type; };

if want manually, try partial specialization:

template< typename ... t > struct type_list {};  template< typename ta, typename tb > struct type_cat;  template< typename ... a, typename ... b > struct type_cat< type_list< ... >, type_list< b ... > >     { typedef type_list< ..., b ... > type; };

as size member, can make universal metafunction solve problem once , all.

template< typename > struct count_types;  template< template< typename ... > class t, typename ... > struct count_types< t< ... > >     { static constexpr std::size_t value = sizeof ... a; };

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