1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
|
// <utility> -*- C++ -*-
// Copyright (C) 2001-2022 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/>.
/*
*
* Copyright (c) 1994
* Hewlett-Packard Company
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Hewlett-Packard Company makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*
*
* Copyright (c) 1996,1997
* Silicon Graphics Computer Systems, Inc.
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Silicon Graphics makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*/
/** @file include/utility
* This is a Standard C++ Library header.
*/
#ifndef _GLIBCXX_UTILITY
#define _GLIBCXX_UTILITY 1
#pragma GCC system_header
/**
* @defgroup utilities Utilities
*
* Basic function and class templates used with the rest of the library.
* Includes pair, swap, forward/move helpers, declval, integer_sequence.
*/
#include <bits/c++config.h>
#include <bits/stl_relops.h>
#include <bits/stl_pair.h>
#if __cplusplus >= 201103L
#include <initializer_list>
#include <type_traits>
#include <bits/move.h>
#include <bits/utility.h>
#if __cplusplus >= 202002L
#include <ext/numeric_traits.h> // __is_standard_integer, __int_traits
#endif
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
#if __cplusplus >= 201402L
#define __cpp_lib_exchange_function 201304L
/// Assign @p __new_val to @p __obj and return its previous value.
template <typename _Tp, typename _Up = _Tp>
_GLIBCXX20_CONSTEXPR
inline _Tp
exchange(_Tp& __obj, _Up&& __new_val)
noexcept(__and_<is_nothrow_move_constructible<_Tp>,
is_nothrow_assignable<_Tp&, _Up>>::value)
{ return std::__exchange(__obj, std::forward<_Up>(__new_val)); }
#if __cplusplus >= 201703L
#define __cpp_lib_as_const 201510L
template<typename _Tp>
[[nodiscard]]
constexpr add_const_t<_Tp>&
as_const(_Tp& __t) noexcept
{ return __t; }
template<typename _Tp>
void as_const(const _Tp&&) = delete;
#if __cplusplus > 201703L
#define __cpp_lib_integer_comparison_functions 202002L
template<typename _Tp, typename _Up>
constexpr bool
cmp_equal(_Tp __t, _Up __u) noexcept
{
static_assert(__is_standard_integer<_Tp>::value);
static_assert(__is_standard_integer<_Up>::value);
if constexpr (is_signed_v<_Tp> == is_signed_v<_Up>)
return __t == __u;
else if constexpr (is_signed_v<_Tp>)
return __t >= 0 && make_unsigned_t<_Tp>(__t) == __u;
else
return __u >= 0 && __t == make_unsigned_t<_Up>(__u);
}
template<typename _Tp, typename _Up>
constexpr bool
cmp_not_equal(_Tp __t, _Up __u) noexcept
{ return !std::cmp_equal(__t, __u); }
template<typename _Tp, typename _Up>
constexpr bool
cmp_less(_Tp __t, _Up __u) noexcept
{
static_assert(__is_standard_integer<_Tp>::value);
static_assert(__is_standard_integer<_Up>::value);
if constexpr (is_signed_v<_Tp> == is_signed_v<_Up>)
return __t < __u;
else if constexpr (is_signed_v<_Tp>)
return __t < 0 || make_unsigned_t<_Tp>(__t) < __u;
else
return __u >= 0 && __t < make_unsigned_t<_Up>(__u);
}
template<typename _Tp, typename _Up>
constexpr bool
cmp_greater(_Tp __t, _Up __u) noexcept
{ return std::cmp_less(__u, __t); }
template<typename _Tp, typename _Up>
constexpr bool
cmp_less_equal(_Tp __t, _Up __u) noexcept
{ return !std::cmp_less(__u, __t); }
template<typename _Tp, typename _Up>
constexpr bool
cmp_greater_equal(_Tp __t, _Up __u) noexcept
{ return !std::cmp_less(__t, __u); }
template<typename _Up, typename _Tp>
constexpr bool
in_range(_Tp __t) noexcept
{
static_assert(__is_standard_integer<_Up>::value);
static_assert(__is_standard_integer<_Tp>::value);
using __gnu_cxx::__int_traits;
if constexpr (is_signed_v<_Tp> == is_signed_v<_Up>)
return __int_traits<_Up>::__min <= __t
&& __t <= __int_traits<_Up>::__max;
else if constexpr (is_signed_v<_Tp>)
return __t >= 0
&& make_unsigned_t<_Tp>(__t) <= __int_traits<_Up>::__max;
else
return __t <= make_unsigned_t<_Up>(__int_traits<_Up>::__max);
}
#if __cplusplus > 202002L
#define __cpp_lib_to_underlying 202102L
/// Convert an object of enumeration type to its underlying type.
template<typename _Tp>
[[nodiscard]]
constexpr underlying_type_t<_Tp>
to_underlying(_Tp __value) noexcept
{ return static_cast<underlying_type_t<_Tp>>(__value); }
#define __cpp_lib_unreachable 202202L
/// Informs the compiler that program control flow never reaches this point.
/**
* Evaluating a call to this function results in undefined behaviour.
* This can be used as an assertion informing the compiler that certain
* conditions are impossible, for when the compiler is unable to determine
* that by itself.
*
* For example, it can be used to prevent warnings about reaching the
* end of a non-void function without returning.
*
* @since C++23
*/
[[noreturn,__gnu__::__always_inline__]]
inline void
unreachable()
{
#ifdef _GLIBCXX_DEBUG
std::__glibcxx_assert_fail(nullptr, 0, "std::unreachable()", nullptr);
#elif defined _GLIBCXX_ASSERTIONS
__builtin_trap();
#else
__builtin_unreachable();
#endif
}
#endif // C++23
#endif // C++20
#endif // C++17
#endif // C++14
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
#endif
#endif /* _GLIBCXX_UTILITY */
|