meta.hpp

#ifndef MRS_LIB_UTILITY_META_HPP_
#define MRS_LIB_UTILITY_META_HPP_
 
#include <cstddef>
 

namespace mrs_lib::meta
{

  template <typename...>
  struct TypeList
  {
  };

  template <typename List, size_t N>
  struct Drop; // Undefined
 
  template <typename... Ts>
  struct Drop<TypeList<Ts...>, size_t(0)>
  {
    using type = TypeList<Ts...>;
  };
 
  template <typename T, typename... Ts, size_t N>
    requires(N > 0)
  struct Drop<TypeList<T, Ts...>, N>
  {
    using type = Drop<TypeList<Ts...>, N - 1>::type;
  };

  template <typename List, size_t N>
  using DropT = Drop<List, N>::type;

  template <template <typename...> typename F, typename List>
  struct Apply; // Undefined
 
  template <template <typename...> typename F, typename... Args>
  struct Apply<F, TypeList<Args...>>
  {
    using type = F<Args...>;
  };

  template <template <typename...> typename F, typename List>
  using ApplyT = Apply<F, List>::type;
 
} // namespace mrs_lib::meta
 
 
#endif // MRS_LIB_UTILITY_META_HPP_