libstdc++
experimental/tuple
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1 // <experimental/tuple> -*- C++ -*-
2 
3 // Copyright (C) 2014-2021 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
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15 
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19 
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24 
25 /** @file experimental/tuple
26  * This is a TS C++ Library header.
27  * @ingroup libfund-ts
28  */
29 
30 #ifndef _GLIBCXX_EXPERIMENTAL_TUPLE
31 #define _GLIBCXX_EXPERIMENTAL_TUPLE 1
32 
33 #pragma GCC system_header
34 
35 #if __cplusplus >= 201402L
36 
37 #include <tuple>
38 #include <bits/invoke.h>
40 
41 namespace std _GLIBCXX_VISIBILITY(default)
42 {
43 _GLIBCXX_BEGIN_NAMESPACE_VERSION
44 
45 namespace experimental
46 {
47 inline namespace fundamentals_v1
48 {
49  // See C++14 20.4.2.5, tuple helper classes
50  template <typename _Tp>
51  constexpr size_t tuple_size_v = tuple_size<_Tp>::value;
52 
53 #define __cpp_lib_experimental_tuple 201402
54 
55  template <typename _Fn, typename _Tuple, std::size_t... _Idx>
56  constexpr decltype(auto)
57  __apply_impl(_Fn&& __f, _Tuple&& __t, std::index_sequence<_Idx...>)
58  {
59  return std::__invoke(std::forward<_Fn>(__f),
60  std::get<_Idx>(std::forward<_Tuple>(__t))...);
61  }
62 
63  template <typename _Fn, typename _Tuple>
64  constexpr decltype(auto)
65  apply(_Fn&& __f, _Tuple&& __t)
66  {
67  using _Indices =
69  return experimental::__apply_impl(std::forward<_Fn>(__f),
70  std::forward<_Tuple>(__t),
71  _Indices{});
72  }
73 } // namespace fundamentals_v1
74 } // namespace experimental
75 
76 _GLIBCXX_END_NAMESPACE_VERSION
77 } // namespace std
78 
79 #endif // C++14
80 
81 #endif // _GLIBCXX_EXPERIMENTAL_TUPLE
constexpr __invoke_result< _Callable, _Args... >::type __invoke(_Callable &&__fn, _Args &&... __args) noexcept(__is_nothrow_invocable< _Callable, _Args... >::value)
Invoke a callable object.
Definition: invoke.h:90
ISO C++ entities toplevel namespace is std.
integer_sequence< size_t, _Idx... > index_sequence
Alias template index_sequence.
Definition: utility:339
Class template integer_sequence.
Definition: utility:323