1 2 #ifndef BOOST_MPL_EMPTY_SEQUENCE_HPP_INCLUDED 3 #define BOOST_MPL_EMPTY_SEQUENCE_HPP_INCLUDED 4 5 // Copyright Aleksey Gurtovoy 2004 6 // Copyright Alexander Nasonov 2004 7 // 8 // Distributed under the Boost Software License, Version 1.0. 9 // (See accompanying file LICENSE_1_0.txt or copy at 10 // http://www.boost.org/LICENSE_1_0.txt) 11 // 12 // See http://www.boost.org/libs/mpl for documentation. 13 14 // $Id$ 15 // $Date$ 16 // $Revision$ 17 18 #include <boost/mpl/size_fwd.hpp> 19 #include <boost/mpl/int.hpp> 20 #include <boost/mpl/iterator_tags.hpp> 21 22 namespace boost { namespace mpl { 23 24 struct empty_sequence 25 { 26 struct tag; 27 typedef empty_sequence type; 28 struct begin { typedef random_access_iterator_tag category; }; 29 typedef begin end; 30 }; 31 32 template<> 33 struct size_impl<empty_sequence::tag> 34 { 35 template< typename Sequence > struct apply 36 : int_<0> 37 { 38 }; 39 }; 40 41 }} 42 43 #endif // #ifndef BOOST_MPL_EMPTY_SEQUENCE_HPP_INCLUDED 44