is_base_template_of.hpp

/*=============================================================================
  Copyright 2018-2020 Pranam Lashkari < lpranam - plashkari628@gmail.com >
  
  Distributed under the Boost Software License, Version 1.0. (See accompanying
  file LICENSE_1_0.txt or copy at https://www.boost.org/LICENSE_1_0.txt)
=============================================================================*/

#ifndef BOOST_ASTRONOMY_DETAIL_IS_BASE_TEMPLATE_OF_HPP
#define BOOST_ASTRONOMY_DETAIL_IS_BASE_TEMPLATE_OF_HPP

#include <cstddef>
#include <type_traits>


namespace boost { namespace astronomy { namespace detail {

///@cond INTERNAL
// structure to provide support like std::is_base_of for template base classes
template <template <std::size_t, typename...> class Base, typename Derived>
struct base_template
{
    //using U = typename std::remove_cv<Derived>::type;

    template <std::size_t T, typename... Args>
    static constexpr std::true_type test(const Base<T, Args...>*);

    static constexpr std::false_type test(...);

    using type = decltype(test(std::declval<Derived*>()));
};

template <template <std::size_t, typename...> class Base, typename Derived>
using is_base_template_of = typename base_template<Base, Derived>::type;


// structure to provide support like std::is_base_of for template base classes
template <template <typename...> class Base, typename Derived>
struct base_frame_template
{
    template <typename... Args>
    static constexpr std::true_type test(const Base<Args...> *);

    static constexpr std::false_type test(...);

    using type = decltype(test(std::declval<Derived*>()));
};

template <template <typename...> class Base, typename Derived>
using is_base_frame_of = typename base_frame_template<Base, Derived>::type;

///@endcond

}}} //namespace boost::astronomy::detail

#endif // !BOOST_ASTRONOMY_DETAIL_IS_BASE_TEMPLATE_OF_HPP