| // -*- C++ -*- |
| |
| // Copyright (C) 2007, 2009 Free Software Foundation, Inc. |
| // |
| // This file is part of the GNU ISO C++ Library. This library is free |
| // software; you can redistribute it and/or modify it under the terms |
| // of the GNU General Public License as published by the Free Software |
| // Foundation; either version 3, or (at your option) any later |
| // version. |
| |
| // This library is distributed in the hope that it will be useful, but |
| // WITHOUT ANY WARRANTY; without even the implied warranty of |
| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| // General Public License for more details. |
| |
| // Under Section 7 of GPL version 3, you are granted additional |
| // permissions described in the GCC Runtime Library Exception, version |
| // 3.1, as published by the Free Software Foundation. |
| |
| // You should have received a copy of the GNU General Public License and |
| // a copy of the GCC Runtime Library Exception along with this program; |
| // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
| // <http://www.gnu.org/licenses/>. |
| |
| /** @file ext/numeric_traits.h |
| * This file is a GNU extension to the Standard C++ Library. |
| */ |
| |
| #ifndef _EXT_NUMERIC_TRAITS |
| #define _EXT_NUMERIC_TRAITS 1 |
| |
| #pragma GCC system_header |
| |
| #include <bits/cpp_type_traits.h> |
| #include <ext/type_traits.h> |
| |
| _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx) |
| |
| // Compile time constants for builtin types. |
| // Sadly std::numeric_limits member functions cannot be used for this. |
| #define __glibcxx_signed(_Tp) ((_Tp)(-1) < 0) |
| #define __glibcxx_digits(_Tp) \ |
| (sizeof(_Tp) * __CHAR_BIT__ - __glibcxx_signed(_Tp)) |
| |
| #define __glibcxx_min(_Tp) \ |
| (__glibcxx_signed(_Tp) ? (_Tp)1 << __glibcxx_digits(_Tp) : (_Tp)0) |
| |
| #define __glibcxx_max(_Tp) \ |
| (__glibcxx_signed(_Tp) ? \ |
| (((((_Tp)1 << (__glibcxx_digits(_Tp) - 1)) - 1) << 1) + 1) : ~(_Tp)0) |
| |
| template<typename _Value> |
| struct __numeric_traits_integer |
| { |
| // Only integers for initialization of member constant. |
| static const _Value __min = __glibcxx_min(_Value); |
| static const _Value __max = __glibcxx_max(_Value); |
| |
| // NB: these two also available in std::numeric_limits as compile |
| // time constants, but <limits> is big and we avoid including it. |
| static const bool __is_signed = __glibcxx_signed(_Value); |
| static const int __digits = __glibcxx_digits(_Value); |
| }; |
| |
| template<typename _Value> |
| const _Value __numeric_traits_integer<_Value>::__min; |
| |
| template<typename _Value> |
| const _Value __numeric_traits_integer<_Value>::__max; |
| |
| template<typename _Value> |
| const bool __numeric_traits_integer<_Value>::__is_signed; |
| |
| template<typename _Value> |
| const int __numeric_traits_integer<_Value>::__digits; |
| |
| #undef __glibcxx_signed |
| #undef __glibcxx_digits |
| #undef __glibcxx_min |
| #undef __glibcxx_max |
| |
| #define __glibcxx_floating(_Tp, _Fval, _Dval, _LDval) \ |
| (std::__are_same<_Tp, float>::__value ? _Fval \ |
| : std::__are_same<_Tp, double>::__value ? _Dval : _LDval) |
| |
| #define __glibcxx_max_digits10(_Tp) \ |
| (2 + __glibcxx_floating(_Tp, __FLT_MANT_DIG__, __DBL_MANT_DIG__, \ |
| __LDBL_MANT_DIG__) * 3010 / 10000) |
| |
| #define __glibcxx_digits10(_Tp) \ |
| __glibcxx_floating(_Tp, __FLT_DIG__, __DBL_DIG__, __LDBL_DIG__) |
| |
| #define __glibcxx_max_exponent10(_Tp) \ |
| __glibcxx_floating(_Tp, __FLT_MAX_10_EXP__, __DBL_MAX_10_EXP__, \ |
| __LDBL_MAX_10_EXP__) |
| |
| template<typename _Value> |
| struct __numeric_traits_floating |
| { |
| // Only floating point types. See N1822. |
| static const int __max_digits10 = __glibcxx_max_digits10(_Value); |
| |
| // See above comment... |
| static const bool __is_signed = true; |
| static const int __digits10 = __glibcxx_digits10(_Value); |
| static const int __max_exponent10 = __glibcxx_max_exponent10(_Value); |
| }; |
| |
| template<typename _Value> |
| const int __numeric_traits_floating<_Value>::__max_digits10; |
| |
| template<typename _Value> |
| const bool __numeric_traits_floating<_Value>::__is_signed; |
| |
| template<typename _Value> |
| const int __numeric_traits_floating<_Value>::__digits10; |
| |
| template<typename _Value> |
| const int __numeric_traits_floating<_Value>::__max_exponent10; |
| |
| template<typename _Value> |
| struct __numeric_traits |
| : public __conditional_type<std::__is_integer<_Value>::__value, |
| __numeric_traits_integer<_Value>, |
| __numeric_traits_floating<_Value> >::__type |
| { }; |
| |
| _GLIBCXX_END_NAMESPACE |
| |
| #undef __glibcxx_floating |
| #undef __glibcxx_max_digits10 |
| #undef __glibcxx_digits10 |
| #undef __glibcxx_max_exponent10 |
| |
| #endif |