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