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Defines `boost::hana::is_a` and `boost::hana::is_an`.

Copyright Louis Dionne 2013-2022
Distributed under the Boost Software License, Version 1.0.
(See accompanying file or copy at


#include <boost/hana/fwd/core/is_a.hpp>

#include <boost/hana/bool.hpp>
#include <boost/hana/config.hpp>
#include <boost/hana/core/tag_of.hpp>

#include <type_traits>

namespace boost { namespace hana {
    // is_a
    template <typename DataType, typename T>
    struct is_a_t<DataType, T>
        : integral_constant<bool,
            std::is_same<DataType, typename hana::tag_of<T>::type>::value
    { };

    template <typename DataType>
    struct is_a_t<DataType> {
        template <typename T>
        constexpr auto operator()(T const&) const
        { return hana::is_a<DataType, T>; }
}} // end namespace boost::hana