named.h

Go to the documentation of this file.

 
//          Copyright John McFarlane 2015 - 2016.
// 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)
 
 
#if !defined(CNL_IMPL_SCALED_INTEGER_NAMED_H)
#define CNL_IMPL_SCALED_INTEGER_NAMED_H
 
#include "../num_traits/rep_of.h"
#include "../num_traits/tag_of.h"
#include "../scaled/power.h"
 
#include <algorithm>
 
namespace cnl {
 
    // cnl::make_scaled_integer<Value>
 
 
    template<typename Value>
    [[nodiscard]] constexpr auto make_scaled_integer(Value const& value)
    {
        return _impl::from_value<scaled_integer<>, Value>(value);
    }
 
    template<fixed_point Numerator, fixed_point Denominator>
    struct fraction;
 
    template<class Dividend, class Divisor>
    [[nodiscard]] constexpr auto make_scaled_integer(fraction<Dividend, Divisor> const& f)
    {
        using natural_result = _impl::op_result<_impl::divide_op, Dividend, Divisor>;
 
        constexpr int integer_digits = _impl::integer_digits<Dividend> + _impl::fractional_digits<Divisor>;
        constexpr int fractional_digits = _impl::fractional_digits<Dividend> + _impl::integer_digits<Divisor>;
 
        constexpr auto necessary_digits = integer_digits + fractional_digits;
        constexpr auto natural_digits = digits_v<natural_result>;
        constexpr auto result_digits = std::max(necessary_digits, natural_digits);
 
        constexpr int rep_exponent = -fractional_digits;
        using scale = power<rep_exponent>;
 
        using rep_type = set_digits_t<natural_result, result_digits>;
        using rep = decltype(_impl::not_scaled_integer(std::declval<rep_type>()));
 
        return _impl::from_rep<scaled_integer<rep, scale>>(
                convert<scale, rep, power<>>{}(f));
    }
 
 
    template<class Dividend, class Divisor>
    [[nodiscard]] constexpr auto quotient(Dividend const& dividend, Divisor const& divisor)
    {
        return make_scaled_integer(make_fraction(dividend, divisor));
    }
}
 
#endif  // CNL_IMPL_SCALED_INTEGER_NAMED_H