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Defines `boost::hana::Functor`.

@copyright Louis Dionne 2013-2017
Distributed under the Boost Software License, Version 1.0.
(See accompanying file or copy at


#include <boost/hana/fwd/concept/functor.hpp>

#include <boost/hana/adjust_if.hpp>
#include <boost/hana/config.hpp>
#include <boost/hana/core/default.hpp>
#include <boost/hana/core/tag_of.hpp>
#include <boost/hana/detail/integral_constant.hpp>
#include <boost/hana/transform.hpp>

namespace boost { namespace hana {
    template <typename F>
    struct Functor
        : hana::integral_constant<bool,
            !is_default<transform_impl<typename tag_of<F>::type>>::value ||
            !is_default<adjust_if_impl<typename tag_of<F>::type>>::value
    { };
}} // end namespace boost::hana