ceph/src/boost/libs/units/include/boost/units/homogeneous_system.hpp

   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) 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_HOMOGENEOUS_SYSTEM_HPP_INCLUDED
  12 #define BOOST_UNITS_HOMOGENEOUS_SYSTEM_HPP_INCLUDED
  13
  14 #include <boost/mpl/bool.hpp>
  15
  16 #include <boost/units/config.hpp>
  17 #include <boost/units/static_rational.hpp>
  18
  19 #ifdef BOOST_UNITS_CHECK_HOMOGENEOUS_UNITS
  20
  21 #include <boost/type_traits/is_same.hpp>
  22 #include <boost/mpl/not.hpp>
  23
  24 #include <boost/units/detail/linear_algebra.hpp>
  25
  26 #endif
  27
  28 namespace boost {
  29
  30 namespace units {
  31
  32 /// A system that can uniquely represent any unit
  33 /// which can be composed from a linearly independent set
  34 /// of base units.  It is safe to rebind a unit with
  35 /// such a system to different dimensions.
  36 ///
  37 /// Do not construct this template directly.  Use
  38 /// make_system instead.
  39 template<class L>
  40 struct homogeneous_system {
  41     /// INTERNAL ONLY
  42     typedef L type;
  43 };
  44
  45 template<class T, class E>
  46 struct static_power;
  47
  48 template<class T, class R>
  49 struct static_root;
  50
  51 /// INTERNAL ONLY
  52 template<class L, long N, long D>
  53 struct static_power<homogeneous_system<L>, static_rational<N,D> >
  54 {
  55     typedef homogeneous_system<L> type;
  56 };
  57
  58 /// INTERNAL ONLY
  59 template<class L, long N, long D>
  60 struct static_root<homogeneous_system<L>, static_rational<N,D> >
  61 {
  62     typedef homogeneous_system<L> type;
  63 };
  64
  65 namespace detail {
  66
  67 template<class System, class Dimensions>
  68 struct check_system;
  69
  70 #ifdef BOOST_UNITS_CHECK_HOMOGENEOUS_UNITS
  71
  72 template<class L, class Dimensions>
  73 struct check_system<homogeneous_system<L>, Dimensions> :
  74     boost::mpl::not_<
  75         boost::is_same<
  76             typename calculate_base_unit_exponents<
  77                 L,
  78                 Dimensions
  79             >::type,
  80             inconsistent
  81         >
  82     > {};
  83
  84 #else
  85
  86 template<class L, class Dimensions>
  87 struct check_system<homogeneous_system<L>, Dimensions> : mpl::true_ {};
  88
  89 #endif
  90
  91 } // namespace detail
  92
  93 } // namespace units
  94
  95 } // namespace boost
  96
  97 #if BOOST_UNITS_HAS_BOOST_TYPEOF
  98
  99 #include BOOST_TYPEOF_INCREMENT_REGISTRATION_GROUP()
 100
 101 BOOST_TYPEOF_REGISTER_TEMPLATE(boost::units::homogeneous_system, (class))
 102
 103 #endif
 104
 105 #endif