vn-verdnaturachat/ios/Pods/boost-for-react-native/boost/units/detail/absolute_impl.hpp

105 lines
3.0 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_ABSOLUTE_IMPL_HPP
#define BOOST_UNITS_ABSOLUTE_IMPL_HPP
#include <iosfwd>
#include <boost/units/config.hpp>
#include <boost/units/conversion.hpp>
#include <boost/units/heterogeneous_system.hpp>
#include <boost/units/units_fwd.hpp>
namespace boost {
namespace units {
/// INTERNAL ONLY
template<class D, class S>
struct reduce_unit<absolute<unit<D, S> > >
{
typedef absolute<typename reduce_unit<unit<D, S> >::type> type;
};
namespace detail {
struct undefined_affine_conversion_base {
static const bool is_defined = false;
};
} // namespace detail
/// INTERNAL ONLY
template<class From, class To>
struct affine_conversion_helper : detail::undefined_affine_conversion_base { };
namespace detail {
template<bool IsDefined, bool ReverseIsDefined>
struct affine_conversion_impl;
template<bool ReverseIsDefined>
struct affine_conversion_impl<true, ReverseIsDefined>
{
template<class Unit1, class Unit2, class T0, class T1>
struct apply {
static T1 value(const T0& t0)
{
return(
t0 *
conversion_factor(Unit1(), Unit2()) +
affine_conversion_helper<typename reduce_unit<Unit1>::type, typename reduce_unit<Unit2>::type>::value());
}
};
};
template<>
struct affine_conversion_impl<false, true>
{
template<class Unit1, class Unit2, class T0, class T1>
struct apply
{
static T1 value(const T0& t0)
{
return(
(t0 - affine_conversion_helper<typename reduce_unit<Unit2>::type, typename reduce_unit<Unit1>::type>::value()) *
conversion_factor(Unit1(), Unit2()));
}
};
};
} // namespace detail
/// INTERNAL ONLY
template<class Unit1, class T1, class Unit2, class T2>
struct conversion_helper<quantity<absolute<Unit1>, T1>, quantity<absolute<Unit2>, T2> >
{
typedef quantity<absolute<Unit1>, T1> from_quantity_type;
typedef quantity<absolute<Unit2>, T2> to_quantity_type;
static to_quantity_type convert(const from_quantity_type& source)
{
return(
to_quantity_type::from_value(
detail::affine_conversion_impl<
affine_conversion_helper<typename reduce_unit<Unit1>::type, typename reduce_unit<Unit2>::type>::is_defined,
affine_conversion_helper<typename reduce_unit<Unit2>::type, typename reduce_unit<Unit1>::type>::is_defined
>::template apply<Unit1, Unit2, T1, T2>::value(source.value())
)
);
}
};
} // namespace units
} // namespace boost
#endif // BOOST_UNITS_ABSOLUTE_IMPL_HPP