;      }      template<typename Seq, typename State, typename F>      BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED      inline typename result_of::fold<          Seq        , State const        , F      >::type      fold(Seq& seq, State const& state, F f)      {          return detail::fold<Seq, State const, F>(seq, state, f);      }      template<typename Seq, typename State, typename F>      BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED      inline typename result_of::fold<          Seq const        , State const        , F      >::type      fold(Seq const& seq, State const& state, F f)      {          return detail::fold<Seq const, State const, F>(seq, state, f);      }      template<typename Seq, typename State, typename F>      BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED      inline typename result_of::fold<          Seq        , State        , F      >::type      fold(Seq& seq, State& state, F f)      {          return detail::fold<Seq, State, F>(seq, state, f);      }      template<typename Seq, typename State, typename F>      BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED      inline typename result_of::fold<          Seq const        , State        , F      >::type      fold(Seq const& seq, State& state, F f)      {          return detail::fold<Seq const, State