91 lines
1.8 KiB
C++
91 lines
1.8 KiB
C++
|
// Boost.Units - A C++ library for zero-overhead dimensional analysis and
|
||
|
|
// unit/quantity manipulation and conversion
|
||
|
|
//
|
||
|
|
// Copyright (C) 2003-2008 Matthias Christian Schabel
|
||
|
|
// Copyright (C) 2008 Steven Watanabe
|
||
|
|
//
|
||
|
|
// Distributed under the Boost Software License, Version 1.0. (See
|
||
|
|
// accompanying file LICENSE_1_0.txt or copy at
|
||
|
|
// http://www.boost.org/LICENSE_1_0.txt)
|
||
|
|
|
||
|
|
#ifndef BOOST_UNITS_DIM_IMPL_HPP
|
||
|
|
#define BOOST_UNITS_DIM_IMPL_HPP
|
||
|
|
|
||
|
|
#include <boost/mpl/bool.hpp>
|
||
|
|
#include <boost/mpl/less.hpp>
|
||
|
|
|
||
|
|
#include <boost/units/units_fwd.hpp>
|
||
|
|
|
||
|
|
/// \file
|
||
|
|
/// \brief Class encapsulating a dimension tag/value pair
|
||
|
|
|
||
|
|
namespace boost {
|
||
|
|
|
||
|
|
namespace units {
|
||
|
|
|
||
|
|
namespace detail {
|
||
|
|
|
||
|
|
struct dim_tag;
|
||
|
|
|
||
|
|
}
|
||
|
|
|
||
|
|
}
|
||
|
|
|
||
|
|
namespace mpl {
|
||
|
|
|
||
|
|
/// Less than comparison for sorting @c dim.
|
||
|
|
template<>
|
||
|
|
struct less_impl<boost::units::detail::dim_tag, boost::units::detail::dim_tag>
|
||
|
|
{
|
||
|
|
template<class T0, class T1>
|
||
|
|
struct apply : mpl::less<typename T0::tag_type, typename T1::tag_type> {};
|
||
|
|
};
|
||
|
|
|
||
|
|
}
|
||
|
|
|
||
|
|
namespace units {
|
||
|
|
|
||
|
|
template<class Tag, class Exponent>
|
||
|
|
struct dim;
|
||
|
|
|
||
|
|
template<long N, long D>
|
||
|
|
class static_rational;
|
||
|
|
|
||
|
|
namespace detail {
|
||
|
|
|
||
|
|
/// Extract @c tag_type from a @c dim.
|
||
|
|
template<typename T>
|
||
|
|
struct get_tag
|
||
|
|
{
|
||
|
|
typedef typename T::tag_type type;
|
||
|
|
};
|
||
|
|
|
||
|
|
/// Extract @c value_type from a @c dim.
|
||
|
|
template<typename T>
|
||
|
|
struct get_value
|
||
|
|
{
|
||
|
|
typedef typename T::value_type type;
|
||
|
|
};
|
||
|
|
|
||
|
|
/// Determine if a @c dim is empty (has a zero exponent).
|
||
|
|
template<class T>
|
||
|
|
struct is_empty_dim;
|
||
|
|
|
||
|
|
template<typename T>
|
||
|
|
struct is_empty_dim< dim<T, static_rational<0, 1> > > :
|
||
|
|
mpl::true_
|
||
|
|
{ };
|
||
|
|
|
||
|
|
template<typename T, typename V>
|
||
|
|
struct is_empty_dim< dim<T, V> > :
|
||
|
|
mpl::false_
|
||
|
|
{ };
|
||
|
|
|
||
|
|
} // namespace detail
|
||
|
|
|
||
|
|
} // namespace units
|
||
|
|
|
||
|
|
} // namespace boost
|
||
|
|
|
||
|
|
#endif // BOOST_UNITS_DIM_IMPL_HPP
|