1 2 #ifndef BOOST_MPL_AT_HPP_INCLUDED 3 #define BOOST_MPL_AT_HPP_INCLUDED 4 5 // Copyright Aleksey Gurtovoy 2000-2004 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 // $Id$ 14 // $Date$ 15 // $Revision$ 16 17 #include <boost/mpl/at_fwd.hpp> 18 #include <boost/mpl/aux_/at_impl.hpp> 19 #include <boost/mpl/long.hpp> 20 #include <boost/mpl/sequence_tag.hpp> 21 #include <boost/mpl/aux_/na_spec.hpp> 22 #include <boost/mpl/aux_/lambda_support.hpp> 23 #include <boost/mpl/aux_/nttp_decl.hpp> 24 25 namespace boost { namespace mpl { 26 27 template< 28 typename BOOST_MPL_AUX_NA_PARAM(Sequence) 29 , typename BOOST_MPL_AUX_NA_PARAM(N) 30 > 31 struct at 32 : at_impl< typename sequence_tag<Sequence>::type > 33 ::template apply< Sequence,N > 34 { 35 BOOST_MPL_AUX_LAMBDA_SUPPORT(2,at,(Sequence,N)) 36 }; 37 38 template< 39 typename Sequence 40 , BOOST_MPL_AUX_NTTP_DECL(long, N) 41 > 42 struct at_c 43 : at_impl< typename sequence_tag<Sequence>::type > 44 ::template apply< Sequence,mpl::long_<N> > 45 { 46 }; 47 48 BOOST_MPL_AUX_NA_SPEC(2, at) 49 50 }} 51 52 #endif // BOOST_MPL_AT_HPP_INCLUDED 53