1 2 #ifndef BOOST_MPL_VECTOR_AUX_FRONT_HPP_INCLUDED 3 #define BOOST_MPL_VECTOR_AUX_FRONT_HPP_INCLUDED 4 5 // Copyright Aleksey Gurtovoy 2000-2008 6 // 7 // Distributed under the Boost Software License, Version 1.0. 8 // (See accompanying file LICENSE_1_0.txt or copy at 9 // http://www.boost.org/LICENSE_1_0.txt) 10 // 11 // See http://www.boost.org/libs/mpl for documentation. 12 13 // $Id: front.hpp 49267 2008-10-11 06:19:02Z agurtovoy $ 14 // $Date: 2008-10-10 23:19:02 -0700 (Fri, 10 Oct 2008) $ 15 // $Revision: 49267 $ 16 17 #include <boost/mpl/front_fwd.hpp> 18 #include <boost/mpl/vector/aux_/at.hpp> 19 #include <boost/mpl/vector/aux_/tag.hpp> 20 #include <boost/mpl/aux_/nttp_decl.hpp> 21 #include <boost/mpl/aux_/config/typeof.hpp> 22 #include <boost/mpl/aux_/config/ctps.hpp> 23 24 namespace boost { namespace mpl { 25 26 #if defined(BOOST_MPL_CFG_TYPEOF_BASED_SEQUENCES) 27 28 template<> 29 struct front_impl< aux::vector_tag > 30 { 31 template< typename Vector > struct apply 32 : v_at<Vector,0> 33 { 34 }; 35 }; 36 37 #else 38 39 #if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION) 40 41 template< BOOST_MPL_AUX_NTTP_DECL(long, n_) > 42 struct front_impl< aux::vector_tag<n_> > 43 { 44 template< typename Vector > struct apply 45 { 46 typedef typename Vector::item0 type; 47 }; 48 }; 49 50 #endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION 51 52 #endif // BOOST_MPL_CFG_TYPEOF_BASED_SEQUENCES 53 54 }} 55 56 #endif // BOOST_MPL_VECTOR_AUX_FRONT_HPP_INCLUDED 57