text: /*!
  @file
  Defines `boost::hana::fuse`.
  
  @copyright Louis Dionne 2013-2017
  Distributed under the Boost Software License, Version 1.0.
  (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
   */
  
  #ifndef BOOST_HANA_FUSE_HPP
  #define BOOST_HANA_FUSE_HPP
  
  #include <boost/hana/fwd/fuse.hpp>
  
  #include <boost/hana/config.hpp>
  #include <boost/hana/detail/decay.hpp>
  #include <boost/hana/unpack.hpp>
  
  
  BOOST_HANA_NAMESPACE_BEGIN
      namespace detail {
          template <typename F>
          struct fused {
              F f;
              template <typename Xs>
              constexpr decltype(auto) operator()(Xs&& xs) const&
              { return hana::unpack(static_cast<Xs&&>(xs), f); }
  
              template <typename Xs>
              constexpr decltype(auto) operator()(Xs&& xs) &
              { return hana::unpack(static_cast<Xs&&>(xs), f); }
  
              template <typename Xs>
              constexpr decltype(auto) operator()(Xs&& xs) &&
              { return hana::unpack(static_cast<Xs&&>(xs), static_cast<F&&>(f)); }
          };
      }
  
      //! @cond
      template <typename F>
      constexpr auto fuse_t::operator()(F&& f) const {
          return detail::fused<typename detail::decay<F>::type>{static_cast<F&&>(f)};
      }
      //! @endcond
  BOOST_HANA_NAMESPACE_END
  
  #endif // !BOOST_HANA_FUSE_HPP
  