Edit: /usr/include/boost/units/dimension.hpp (4403B)
// 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) 2007-2008 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_DIMENSION_HPP
#define BOOST_UNITS_DIMENSION_HPP
#include
#include
#include
#include
#include
#include
/// \file
/// \brief Core metaprogramming utilities for compile-time dimensional analysis.
namespace boost {
namespace units {
/// Reduce dimension list to cardinal form. This algorithm collapses duplicate
/// base dimension tags and sorts the resulting list by the tag ordinal value.
/// Dimension lists that resolve to the same dimension are guaranteed to be
/// represented by an identical type.
///
/// The argument should be an MPL forward sequence containing instances
/// of the @c dim template.
///
/// The result is also an MPL forward sequence. It also supports the
/// following metafunctions to allow use as a dimension.
///
/// - @c mpl::plus is defined only on two equal dimensions and returns the argument unchanged.
/// - @c mpl::minus is defined only for two equal dimensions and returns the argument unchanged.
/// - @c mpl::negate will return its argument unchanged.
/// - @c mpl::times is defined for any dimensions and adds corresponding exponents.
/// - @c mpl::divides is defined for any dimensions and subtracts the exponents of the
/// right had argument from the corresponding exponents of the left had argument.
/// Missing base dimension tags are assumed to have an exponent of zero.
/// - @c static_power takes a dimension and a static_rational and multiplies all
/// the exponents of the dimension by the static_rational.
/// - @c static_root takes a dimension and a static_rational and divides all
/// the exponents of the dimension by the static_rational.
template
struct make_dimension_list
{
typedef typename detail::sort_dims::type type;
};
/// Raise a dimension list to a scalar power.
template
struct static_power
{
typedef typename detail::static_power_impl::template apply<
DL,
Ex
>::type type;
};
/// Take a scalar root of a dimension list.
template
struct static_root
{
typedef typename detail::static_root_impl::template apply<
DL,
Rt
>::type type;
};
} // namespace units
#ifndef BOOST_UNITS_DOXYGEN
namespace mpl {
template<>
struct plus_impl
{
template
struct apply
{
BOOST_STATIC_ASSERT((boost::is_same::value == true));
typedef T0 type;
};
};
template<>
struct minus_impl
{
template
struct apply
{
BOOST_STATIC_ASSERT((boost::is_same::value == true));
typedef T0 type;
};
};
template<>
struct times_impl
{
template
struct apply
{
typedef typename boost::units::detail::merge_dimensions::type type;
};
};
template<>
struct divides_impl
{
template
struct apply
{
typedef typename boost::units::detail::merge_dimensions<
T0,
typename boost::units::detail::static_inverse_impl<
T1::size::value
>::template apply<
T1
>::type
>::type type;
};
};
template<>
struct negate_impl
{
template
struct apply
{
typedef T0 type;
};
};
} // namespace mpl
#endif
} // namespace boost
#endif // BOOST_UNITS_DIMENSION_HPP