1 | // Boost.Units - A C++ library for zero-overhead dimensional analysis and |
---|---|
2 | // unit/quantity manipulation and conversion |
3 | // |
4 | // Copyright (C) 2003-2008 Matthias Christian Schabel |
5 | // Copyright (C) 2007-2008 Steven Watanabe |
6 | // |
7 | // Distributed under the Boost Software License, Version 1.0. (See |
8 | // accompanying file LICENSE_1_0.txt or copy at |
9 | // http://www.boost.org/LICENSE_1_0.txt) |
10 | |
11 | #ifndef BOOST_UNITS_DIMENSIONLESS_TYPE_HPP |
12 | #define BOOST_UNITS_DIMENSIONLESS_TYPE_HPP |
13 | |
14 | /// |
15 | /// \file |
16 | /// \brief Dimension lists in which all exponents resolve to zero reduce to @c dimensionless_type. |
17 | /// |
18 | |
19 | #include <boost/mpl/long.hpp> |
20 | #include <boost/mpl/deref.hpp> |
21 | #include <boost/mpl/arithmetic.hpp> |
22 | |
23 | #include <boost/units/config.hpp> |
24 | |
25 | namespace boost { |
26 | |
27 | namespace units { |
28 | |
29 | namespace detail { |
30 | |
31 | struct dimension_list_tag; |
32 | |
33 | } |
34 | |
35 | /// Dimension lists in which all exponents resolve to zero reduce to @c dimensionless_type. |
36 | struct dimensionless_type |
37 | { |
38 | typedef dimensionless_type type; |
39 | typedef detail::dimension_list_tag tag; |
40 | typedef mpl::long_<0> size; |
41 | }; |
42 | |
43 | } // namespace units |
44 | |
45 | } // namespace boost |
46 | |
47 | #if BOOST_UNITS_HAS_BOOST_TYPEOF |
48 | |
49 | #include BOOST_TYPEOF_INCREMENT_REGISTRATION_GROUP() |
50 | |
51 | BOOST_TYPEOF_REGISTER_TYPE(boost::units::dimensionless_type) |
52 | |
53 | #endif |
54 | |
55 | #endif // BOOST_UNITS_DIMENSIONLESS_TYPE_HPP |
56 |