1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
3//
4//                     The LLVM Compiler Infrastructure
5//
6// This file is dual licensed under the MIT and the University of Illinois Open
7// Source Licenses. See LICENSE.TXT for details.
8//
9//===----------------------------------------------------------------------===//
10
11#ifndef _LIBCPP___TUPLE
12#define _LIBCPP___TUPLE
13
14#include <__config>
15#include <cstddef>
16#include <type_traits>
17
18#pragma GCC system_header
19
20#ifdef _LIBCPP_HAS_NO_VARIADICS
21
22#include <__tuple_03>
23
24#else  // _LIBCPP_HAS_NO_VARIADICS
25
26_LIBCPP_BEGIN_NAMESPACE_STD
27
28template <class _Tp> class _LIBCPP_VISIBLE tuple_size;
29
30template <class _Tp>
31class _LIBCPP_VISIBLE tuple_size<const _Tp>
32    : public tuple_size<_Tp> {};
33
34template <class _Tp>
35class _LIBCPP_VISIBLE tuple_size<volatile _Tp>
36    : public tuple_size<_Tp> {};
37
38template <class _Tp>
39class _LIBCPP_VISIBLE tuple_size<const volatile _Tp>
40    : public tuple_size<_Tp> {};
41
42template <size_t _Ip, class _Tp> class _LIBCPP_VISIBLE tuple_element;
43
44template <size_t _Ip, class _Tp>
45class _LIBCPP_VISIBLE tuple_element<_Ip, const _Tp>
46{
47public:
48    typedef typename add_const<typename tuple_element<_Ip, _Tp>::type>::type type;
49};
50
51template <size_t _Ip, class _Tp>
52class _LIBCPP_VISIBLE tuple_element<_Ip, volatile _Tp>
53{
54public:
55    typedef typename add_volatile<typename tuple_element<_Ip, _Tp>::type>::type type;
56};
57
58template <size_t _Ip, class _Tp>
59class _LIBCPP_VISIBLE tuple_element<_Ip, const volatile _Tp>
60{
61public:
62    typedef typename add_cv<typename tuple_element<_Ip, _Tp>::type>::type type;
63};
64
65template <class ..._Tp> class _LIBCPP_VISIBLE tuple;
66template <class _T1, class _T2> class _LIBCPP_VISIBLE pair;
67template <class _Tp, size_t _Size> struct _LIBCPP_VISIBLE array;
68
69template <class _Tp> struct __tuple_like : false_type {};
70
71template <class _Tp> struct __tuple_like<const _Tp> : public __tuple_like<_Tp> {};
72template <class _Tp> struct __tuple_like<volatile _Tp> : public __tuple_like<_Tp> {};
73template <class _Tp> struct __tuple_like<const volatile _Tp> : public __tuple_like<_Tp> {};
74
75template <class... _Tp> struct __tuple_like<tuple<_Tp...> > : true_type {};
76template <class _T1, class _T2> struct __tuple_like<pair<_T1, _T2> > : true_type {};
77template <class _Tp, size_t _Size> struct __tuple_like<array<_Tp, _Size> > : true_type {};
78
79template <size_t _Ip, class ..._Tp>
80typename tuple_element<_Ip, tuple<_Tp...> >::type&
81get(tuple<_Tp...>&);
82
83template <size_t _Ip, class ..._Tp>
84const typename tuple_element<_Ip, tuple<_Tp...> >::type&
85get(const tuple<_Tp...>&);
86
87template <size_t _Ip, class ..._Tp>
88typename tuple_element<_Ip, tuple<_Tp...> >::type&&
89get(tuple<_Tp...>&&);
90
91template <size_t _Ip, class _T1, class _T2>
92typename tuple_element<_Ip, pair<_T1, _T2> >::type&
93get(pair<_T1, _T2>&);
94
95template <size_t _Ip, class _T1, class _T2>
96const typename tuple_element<_Ip, pair<_T1, _T2> >::type&
97get(const pair<_T1, _T2>&);
98
99template <size_t _Ip, class _T1, class _T2>
100typename tuple_element<_Ip, pair<_T1, _T2> >::type&&
101get(pair<_T1, _T2>&&);
102
103template <size_t _Ip, class _Tp, size_t _Size>
104_Tp&
105get(array<_Tp, _Size>&);
106
107template <size_t _Ip, class _Tp, size_t _Size>
108const _Tp&
109get(const array<_Tp, _Size>&);
110
111template <size_t _Ip, class _Tp, size_t _Size>
112_Tp&&
113get(array<_Tp, _Size>&&);
114
115// __make_tuple_indices
116
117template <size_t...> struct __tuple_indices {};
118
119template <size_t _Sp, class _IntTuple, size_t _Ep>
120struct __make_indices_imp;
121
122template <size_t _Sp, size_t ..._Indices, size_t _Ep>
123struct __make_indices_imp<_Sp, __tuple_indices<_Indices...>, _Ep>
124{
125    typedef typename __make_indices_imp<_Sp+1, __tuple_indices<_Indices..., _Sp>, _Ep>::type type;
126};
127
128template <size_t _Ep, size_t ..._Indices>
129struct __make_indices_imp<_Ep, __tuple_indices<_Indices...>, _Ep>
130{
131    typedef __tuple_indices<_Indices...> type;
132};
133
134template <size_t _Ep, size_t _Sp = 0>
135struct __make_tuple_indices
136{
137    static_assert(_Sp <= _Ep, "__make_tuple_indices input error");
138    typedef typename __make_indices_imp<_Sp, __tuple_indices<>, _Ep>::type type;
139};
140
141// __tuple_types
142
143template <class ..._Tp> struct __tuple_types {};
144
145template <size_t _Ip>
146class _LIBCPP_VISIBLE tuple_element<_Ip, __tuple_types<> >
147{
148public:
149    static_assert(_Ip == 0, "tuple_element index out of range");
150    static_assert(_Ip != 0, "tuple_element index out of range");
151};
152
153template <class _Hp, class ..._Tp>
154class _LIBCPP_VISIBLE tuple_element<0, __tuple_types<_Hp, _Tp...> >
155{
156public:
157    typedef _Hp type;
158};
159
160template <size_t _Ip, class _Hp, class ..._Tp>
161class _LIBCPP_VISIBLE tuple_element<_Ip, __tuple_types<_Hp, _Tp...> >
162{
163public:
164    typedef typename tuple_element<_Ip-1, __tuple_types<_Tp...> >::type type;
165};
166
167template <class ..._Tp>
168class _LIBCPP_VISIBLE tuple_size<__tuple_types<_Tp...> >
169    : public integral_constant<size_t, sizeof...(_Tp)>
170{
171};
172
173template <class... _Tp> struct __tuple_like<__tuple_types<_Tp...> > : true_type {};
174
175// __make_tuple_types
176
177// __make_tuple_types<_Tuple<_Types...>, _Ep, _Sp>::type is a
178// __tuple_types<_Types...> using only those _Types in the range [_Sp, _Ep).
179// _Sp defaults to 0 and _Ep defaults to tuple_size<_Tuple>.  If _Tuple is a
180// lvalue_reference type, then __tuple_types<_Types&...> is the result.
181
182template <class _TupleTypes, class _Tp, size_t _Sp, size_t _Ep>
183struct __make_tuple_types_imp;
184
185template <class ..._Types, class _Tp, size_t _Sp, size_t _Ep>
186struct __make_tuple_types_imp<__tuple_types<_Types...>, _Tp, _Sp, _Ep>
187{
188    typedef typename remove_reference<_Tp>::type _Tpr;
189    typedef typename __make_tuple_types_imp<__tuple_types<_Types...,
190                                            typename conditional<is_lvalue_reference<_Tp>::value,
191                                                typename tuple_element<_Sp, _Tpr>::type&,
192                                                typename tuple_element<_Sp, _Tpr>::type>::type>,
193                                            _Tp, _Sp+1, _Ep>::type type;
194};
195
196template <class ..._Types, class _Tp, size_t _Ep>
197struct __make_tuple_types_imp<__tuple_types<_Types...>, _Tp, _Ep, _Ep>
198{
199    typedef __tuple_types<_Types...> type;
200};
201
202template <class _Tp, size_t _Ep = tuple_size<typename remove_reference<_Tp>::type>::value, size_t _Sp = 0>
203struct __make_tuple_types
204{
205    static_assert(_Sp <= _Ep, "__make_tuple_types input error");
206    typedef typename __make_tuple_types_imp<__tuple_types<>, _Tp, _Sp, _Ep>::type type;
207};
208
209// __tuple_convertible
210
211template <bool, class _Tp, class _Up>
212struct __tuple_convertible_imp : public false_type {};
213
214template <class _Tp0, class ..._Tp, class _Up0, class ..._Up>
215struct __tuple_convertible_imp<true, __tuple_types<_Tp0, _Tp...>, __tuple_types<_Up0, _Up...> >
216    : public integral_constant<bool,
217                               is_convertible<_Tp0, _Up0>::value &&
218                               __tuple_convertible_imp<true, __tuple_types<_Tp...>, __tuple_types<_Up...> >::value> {};
219
220template <>
221struct __tuple_convertible_imp<true, __tuple_types<>, __tuple_types<> >
222    : public true_type {};
223
224template <class _Tp, class _Up, bool = __tuple_like<typename remove_reference<_Tp>::type>::value,
225                                bool = __tuple_like<_Up>::value>
226struct __tuple_convertible
227    : public false_type {};
228
229template <class _Tp, class _Up>
230struct __tuple_convertible<_Tp, _Up, true, true>
231    : public __tuple_convertible_imp<tuple_size<typename remove_reference<_Tp>::type>::value ==
232                                     tuple_size<_Up>::value,
233             typename __make_tuple_types<_Tp>::type, typename __make_tuple_types<_Up>::type>
234{};
235
236// __tuple_assignable
237
238template <bool, class _Tp, class _Up>
239struct __tuple_assignable_imp : public false_type {};
240
241template <class _Tp0, class ..._Tp, class _Up0, class ..._Up>
242struct __tuple_assignable_imp<true, __tuple_types<_Tp0, _Tp...>, __tuple_types<_Up0, _Up...> >
243    : public integral_constant<bool,
244                               is_assignable<_Up0&, _Tp0>::value &&
245                               __tuple_assignable_imp<true, __tuple_types<_Tp...>, __tuple_types<_Up...> >::value> {};
246
247template <>
248struct __tuple_assignable_imp<true, __tuple_types<>, __tuple_types<> >
249    : public true_type {};
250
251template <class _Tp, class _Up, bool = __tuple_like<typename remove_reference<_Tp>::type>::value,
252                                bool = __tuple_like<_Up>::value>
253struct __tuple_assignable
254    : public false_type {};
255
256template <class _Tp, class _Up>
257struct __tuple_assignable<_Tp, _Up, true, true>
258    : public __tuple_assignable_imp<tuple_size<typename remove_reference<_Tp>::type>::value ==
259                                    tuple_size<_Up>::value,
260             typename __make_tuple_types<_Tp>::type, typename __make_tuple_types<_Up>::type>
261{};
262
263_LIBCPP_END_NAMESPACE_STD
264
265#endif  // _LIBCPP_HAS_NO_VARIADICS
266
267#endif  // _LIBCPP___TUPLE
268