]>
Commit | Line | Data |
---|---|---|
b3726dab PC |
1 | // -*- C++ -*- |
2 | ||
3 | // Copyright (C) 2007 Free Software Foundation, Inc. | |
4 | // | |
5 | // This file is part of the GNU ISO C++ Library. This library is free | |
6 | // software; you can redistribute it and/or modify it under the terms | |
7 | // of the GNU General Public License as published by the Free Software | |
8 | // Foundation; either version 2, or (at your option) any later | |
9 | // version. | |
10 | ||
11 | // This library is distributed in the hope that it will be useful, but | |
12 | // WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
14 | // General Public License for more details. | |
15 | ||
16 | // You should have received a copy of the GNU General Public License along | |
17 | // with this library; see the file COPYING. If not, write to the Free | |
18 | // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, | |
19 | // USA. | |
20 | ||
21 | // As a special exception, you may use this file as part of a free | |
22 | // software library without restriction. Specifically, if other files | |
23 | // instantiate templates or use macros or inline functions from this | |
24 | // file, or you compile this file and link it with other files to | |
25 | // produce an executable, this file does not by itself cause the | |
26 | // resulting executable to be covered by the GNU General Public | |
27 | // License. This exception does not however invalidate any other | |
28 | // reasons why the executable file might be covered by the GNU General | |
29 | // Public License. | |
30 | ||
31 | /** @file ext/numeric_traits.h | |
32 | * This file is a GNU extension to the Standard C++ Library. | |
33 | */ | |
34 | ||
35 | #ifndef _EXT_NUMERIC_TRAITS | |
36 | #define _EXT_NUMERIC_TRAITS 1 | |
37 | ||
38 | #pragma GCC system_header | |
39 | ||
40 | #include <limits> | |
41 | #include <bits/cpp_type_traits.h> | |
42 | #include <ext/type_traits.h> | |
43 | ||
44 | _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx) | |
45 | ||
46 | // Compile time constants for builtin types. | |
47 | // Sadly std::numeric_limits member functions cannot be used for this. | |
48 | #define __glibcxx_signed(_Tp) ((_Tp)(-1) < 0) | |
49 | #define __glibcxx_digits(_Tp) \ | |
50 | (sizeof(_Tp) * __CHAR_BIT__ - __glibcxx_signed(_Tp)) | |
51 | ||
52 | #define __glibcxx_min(_Tp) \ | |
53 | (__glibcxx_signed(_Tp) ? (_Tp)1 << __glibcxx_digits(_Tp) : (_Tp)0) | |
54 | ||
55 | #define __glibcxx_max(_Tp) \ | |
56 | (__glibcxx_signed(_Tp) ? \ | |
57 | (((((_Tp)1 << (__glibcxx_digits(_Tp) - 1)) - 1) << 1) + 1) : ~(_Tp)0) | |
58 | ||
59 | template<typename _Value> | |
60 | struct __numeric_traits_integer | |
61 | { | |
62 | // Only integers for initialization of member constant. | |
63 | static const _Value __min = __glibcxx_min(_Value); | |
64 | static const _Value __max = __glibcxx_max(_Value); | |
65 | }; | |
66 | ||
67 | template<typename _Value> | |
68 | const _Value __numeric_traits_integer<_Value>::__min; | |
69 | ||
70 | template<typename _Value> | |
71 | const _Value __numeric_traits_integer<_Value>::__max; | |
72 | ||
73 | template<typename _Value> | |
74 | struct __numeric_traits_floating | |
75 | { | |
76 | // Only floating point types. See N1822. | |
77 | static const int __max_digits10 = | |
78 | 2 + std::numeric_limits<_Value>::digits * 3010/10000; | |
79 | }; | |
80 | ||
81 | template<typename _Value> | |
82 | const int __numeric_traits_floating<_Value>::__max_digits10; | |
83 | ||
84 | template<typename _Value> | |
85 | struct __numeric_traits | |
86 | : public __conditional_type<std::__is_integer<_Value>::__value, | |
87 | __numeric_traits_integer<_Value>, | |
88 | __numeric_traits_floating<_Value> >::__type | |
89 | { }; | |
90 | ||
91 | _GLIBCXX_END_NAMESPACE | |
92 | ||
93 | #undef __glibcxx_signed | |
94 | #undef __glibcxx_min | |
95 | #undef __glibcxx_max | |
96 | #undef __glibcxx_digits | |
97 | ||
98 | #endif |