mirror of
https://github.com/bolero-MURAKAMI/Sprout
synced 2024-11-12 21:09:01 +00:00
69 lines
2.1 KiB
C++
69 lines
2.1 KiB
C++
/*=============================================================================
|
|
Copyright (c) 2011-2017 Bolero MURAKAMI
|
|
https://github.com/bolero-MURAKAMI/Sprout
|
|
|
|
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 SPROUT_RANDOM_DETAIL_SIGNED_UNSIGNED_TOOLS_HPP
|
|
#define SPROUT_RANDOM_DETAIL_SIGNED_UNSIGNED_TOOLS_HPP
|
|
|
|
#include <type_traits>
|
|
#include <sprout/config.hpp>
|
|
#include <sprout/limits.hpp>
|
|
|
|
namespace sprout {
|
|
namespace random {
|
|
namespace detail {
|
|
template<typename T, bool B = sprout::numeric_limits<T>::is_signed>
|
|
struct subtract {};
|
|
template<typename T>
|
|
struct subtract<T, false> {
|
|
public:
|
|
typedef T result_type;
|
|
public:
|
|
SPROUT_CONSTEXPR result_type operator()(T x, T y) const {
|
|
return x - y;
|
|
}
|
|
};
|
|
template<typename T>
|
|
struct subtract<T, true> {
|
|
public:
|
|
typedef typename std::make_unsigned<T>::type result_type;
|
|
public:
|
|
SPROUT_CONSTEXPR result_type operator()(T x, T y) const {
|
|
return y >= 0 ? result_type(x) - result_type(y)
|
|
: x >= 0 ? result_type(x) + result_type(-(y + 1)) + 1
|
|
: result_type(x - y)
|
|
;
|
|
}
|
|
};
|
|
|
|
template<typename T1, typename T2, bool B = sprout::numeric_limits<T2>::is_signed>
|
|
struct add {};
|
|
template<typename T1, typename T2>
|
|
struct add<T1, T2, false> {
|
|
public:
|
|
typedef T2 result_type;
|
|
public:
|
|
SPROUT_CONSTEXPR result_type operator()(T1 x, T2 y) const {
|
|
return T2(x) + y;
|
|
}
|
|
};
|
|
template<typename T1, typename T2>
|
|
struct add<T1, T2, true> {
|
|
public:
|
|
typedef T2 result_type;
|
|
public:
|
|
SPROUT_CONSTEXPR result_type operator()(T1 x, T2 y) const {
|
|
return y >= 0 ? T2(x) + y
|
|
: x >= T1(-(y + 1)) ? T2(x - T1(-(y + 1)) - 1)
|
|
: T2(x) + y
|
|
;
|
|
}
|
|
};
|
|
} // namespace detail
|
|
} // namespace random
|
|
} // namespace sprout
|
|
|
|
#endif // SPROUT_RANDOM_DETAIL_SIGNED_UNSIGNED_TOOLS_HPP
|