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#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
19#pragma GCC system_header
20#endif
21
22
23_LIBCPP_BEGIN_NAMESPACE_STD
24
25template <class _Tp> class _LIBCPP_TYPE_VIS_ONLY tuple_size;
26
27template <class _Tp>
28class _LIBCPP_TYPE_VIS_ONLY tuple_size<const _Tp>
29    : public tuple_size<_Tp> {};
30
31template <class _Tp>
32class _LIBCPP_TYPE_VIS_ONLY tuple_size<volatile _Tp>
33    : public tuple_size<_Tp> {};
34
35template <class _Tp>
36class _LIBCPP_TYPE_VIS_ONLY tuple_size<const volatile _Tp>
37    : public tuple_size<_Tp> {};
38
39template <size_t _Ip, class _Tp> class _LIBCPP_TYPE_VIS_ONLY tuple_element;
40
41template <size_t _Ip, class _Tp>
42class _LIBCPP_TYPE_VIS_ONLY tuple_element<_Ip, const _Tp>
43{
44public:
45    typedef typename add_const<typename tuple_element<_Ip, _Tp>::type>::type type;
46};
47
48template <size_t _Ip, class _Tp>
49class _LIBCPP_TYPE_VIS_ONLY tuple_element<_Ip, volatile _Tp>
50{
51public:
52    typedef typename add_volatile<typename tuple_element<_Ip, _Tp>::type>::type type;
53};
54
55template <size_t _Ip, class _Tp>
56class _LIBCPP_TYPE_VIS_ONLY tuple_element<_Ip, const volatile _Tp>
57{
58public:
59    typedef typename add_cv<typename tuple_element<_Ip, _Tp>::type>::type type;
60};
61
62template <class _Tp> struct __tuple_like : false_type {};
63
64template <class _Tp> struct __tuple_like<const _Tp> : public __tuple_like<_Tp> {};
65template <class _Tp> struct __tuple_like<volatile _Tp> : public __tuple_like<_Tp> {};
66template <class _Tp> struct __tuple_like<const volatile _Tp> : public __tuple_like<_Tp> {};
67
68// tuple specializations
69
70#if !defined(_LIBCPP_HAS_NO_VARIADICS)
71template <class ..._Tp> class _LIBCPP_TYPE_VIS_ONLY tuple;
72
73template <class... _Tp> struct __tuple_like<tuple<_Tp...> > : true_type {};
74
75template <size_t _Ip, class ..._Tp>
76_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
77typename tuple_element<_Ip, tuple<_Tp...> >::type&
78get(tuple<_Tp...>&) _NOEXCEPT;
79
80template <size_t _Ip, class ..._Tp>
81_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
82const typename tuple_element<_Ip, tuple<_Tp...> >::type&
83get(const tuple<_Tp...>&) _NOEXCEPT;
84
85template <size_t _Ip, class ..._Tp>
86_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
87typename tuple_element<_Ip, tuple<_Tp...> >::type&&
88get(tuple<_Tp...>&&) _NOEXCEPT;
89
90template <size_t _Ip, class ..._Tp>
91_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
92const typename tuple_element<_Ip, tuple<_Tp...> >::type&&
93get(const tuple<_Tp...>&&) _NOEXCEPT;
94#endif
95
96// pair specializations
97
98template <class _T1, class _T2> struct _LIBCPP_TYPE_VIS_ONLY pair;
99
100template <class _T1, class _T2> struct __tuple_like<pair<_T1, _T2> > : true_type {};
101
102template <size_t _Ip, class _T1, class _T2>
103_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
104typename tuple_element<_Ip, pair<_T1, _T2> >::type&
105get(pair<_T1, _T2>&) _NOEXCEPT;
106
107template <size_t _Ip, class _T1, class _T2>
108_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
109const typename tuple_element<_Ip, pair<_T1, _T2> >::type&
110get(const pair<_T1, _T2>&) _NOEXCEPT;
111
112#if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
113template <size_t _Ip, class _T1, class _T2>
114_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
115typename tuple_element<_Ip, pair<_T1, _T2> >::type&&
116get(pair<_T1, _T2>&&) _NOEXCEPT;
117
118template <size_t _Ip, class _T1, class _T2>
119_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
120const typename tuple_element<_Ip, pair<_T1, _T2> >::type&&
121get(const pair<_T1, _T2>&&) _NOEXCEPT;
122#endif
123
124// array specializations
125
126template <class _Tp, size_t _Size> struct _LIBCPP_TYPE_VIS_ONLY array;
127
128template <class _Tp, size_t _Size> struct __tuple_like<array<_Tp, _Size> > : true_type {};
129
130template <size_t _Ip, class _Tp, size_t _Size>
131_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
132_Tp&
133get(array<_Tp, _Size>&) _NOEXCEPT;
134
135template <size_t _Ip, class _Tp, size_t _Size>
136_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
137const _Tp&
138get(const array<_Tp, _Size>&) _NOEXCEPT;
139
140#if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
141template <size_t _Ip, class _Tp, size_t _Size>
142_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
143_Tp&&
144get(array<_Tp, _Size>&&) _NOEXCEPT;
145
146template <size_t _Ip, class _Tp, size_t _Size>
147_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
148const _Tp&&
149get(const array<_Tp, _Size>&&) _NOEXCEPT;
150#endif
151
152#if !defined(_LIBCPP_HAS_NO_VARIADICS)
153
154// __make_tuple_indices
155
156template <size_t...> struct __tuple_indices {};
157
158template <size_t _Sp, class _IntTuple, size_t _Ep>
159struct __make_indices_imp;
160
161template <size_t _Sp, size_t ..._Indices, size_t _Ep>
162struct __make_indices_imp<_Sp, __tuple_indices<_Indices...>, _Ep>
163{
164    typedef typename __make_indices_imp<_Sp+1, __tuple_indices<_Indices..., _Sp>, _Ep>::type type;
165};
166
167template <size_t _Ep, size_t ..._Indices>
168struct __make_indices_imp<_Ep, __tuple_indices<_Indices...>, _Ep>
169{
170    typedef __tuple_indices<_Indices...> type;
171};
172
173template <size_t _Ep, size_t _Sp = 0>
174struct __make_tuple_indices
175{
176    static_assert(_Sp <= _Ep, "__make_tuple_indices input error");
177    typedef typename __make_indices_imp<_Sp, __tuple_indices<>, _Ep>::type type;
178};
179
180// __tuple_types
181
182template <class ..._Tp> struct __tuple_types {};
183
184template <size_t _Ip>
185class _LIBCPP_TYPE_VIS_ONLY tuple_element<_Ip, __tuple_types<> >
186{
187public:
188    static_assert(_Ip == 0, "tuple_element index out of range");
189    static_assert(_Ip != 0, "tuple_element index out of range");
190};
191
192template <class _Hp, class ..._Tp>
193class _LIBCPP_TYPE_VIS_ONLY tuple_element<0, __tuple_types<_Hp, _Tp...> >
194{
195public:
196    typedef _Hp type;
197};
198
199template <size_t _Ip, class _Hp, class ..._Tp>
200class _LIBCPP_TYPE_VIS_ONLY tuple_element<_Ip, __tuple_types<_Hp, _Tp...> >
201{
202public:
203    typedef typename tuple_element<_Ip-1, __tuple_types<_Tp...> >::type type;
204};
205
206template <class ..._Tp>
207class _LIBCPP_TYPE_VIS_ONLY tuple_size<__tuple_types<_Tp...> >
208    : public integral_constant<size_t, sizeof...(_Tp)>
209{
210};
211
212template <class... _Tp> struct __tuple_like<__tuple_types<_Tp...> > : true_type {};
213
214// __make_tuple_types
215
216// __make_tuple_types<_Tuple<_Types...>, _Ep, _Sp>::type is a
217// __tuple_types<_Types...> using only those _Types in the range [_Sp, _Ep).
218// _Sp defaults to 0 and _Ep defaults to tuple_size<_Tuple>.  If _Tuple is a
219// lvalue_reference type, then __tuple_types<_Types&...> is the result.
220
221template <class _TupleTypes, class _Tp, size_t _Sp, size_t _Ep>
222struct __make_tuple_types_imp;
223
224template <class ..._Types, class _Tp, size_t _Sp, size_t _Ep>
225struct __make_tuple_types_imp<__tuple_types<_Types...>, _Tp, _Sp, _Ep>
226{
227    typedef typename remove_reference<_Tp>::type _Tpr;
228    typedef typename __make_tuple_types_imp<__tuple_types<_Types...,
229                                            typename conditional<is_lvalue_reference<_Tp>::value,
230                                                typename tuple_element<_Sp, _Tpr>::type&,
231                                                typename tuple_element<_Sp, _Tpr>::type>::type>,
232                                            _Tp, _Sp+1, _Ep>::type type;
233};
234
235template <class ..._Types, class _Tp, size_t _Ep>
236struct __make_tuple_types_imp<__tuple_types<_Types...>, _Tp, _Ep, _Ep>
237{
238    typedef __tuple_types<_Types...> type;
239};
240
241template <class _Tp, size_t _Ep = tuple_size<typename remove_reference<_Tp>::type>::value, size_t _Sp = 0>
242struct __make_tuple_types
243{
244    static_assert(_Sp <= _Ep, "__make_tuple_types input error");
245    typedef typename __make_tuple_types_imp<__tuple_types<>, _Tp, _Sp, _Ep>::type type;
246};
247
248// __tuple_convertible
249
250template <class, class>
251struct __tuple_convertible_imp : public false_type {};
252
253template <class _Tp0, class ..._Tp, class _Up0, class ..._Up>
254struct __tuple_convertible_imp<__tuple_types<_Tp0, _Tp...>, __tuple_types<_Up0, _Up...> >
255    : public integral_constant<bool,
256                               is_convertible<_Tp0, _Up0>::value &&
257                               __tuple_convertible_imp<__tuple_types<_Tp...>, __tuple_types<_Up...> >::value> {};
258
259template <>
260struct __tuple_convertible_imp<__tuple_types<>, __tuple_types<> >
261    : public true_type {};
262
263template <bool, class, class>
264struct __tuple_convertible_apply : public false_type {};
265
266template <class _Tp, class _Up>
267struct __tuple_convertible_apply<true, _Tp, _Up>
268  : public __tuple_convertible_imp<
269      typename __make_tuple_types<_Tp>::type
270    , typename __make_tuple_types<_Up>::type
271    >
272{};
273
274template <class _Tp, class _Up, bool = __tuple_like<typename remove_reference<_Tp>::type>::value,
275                                bool = __tuple_like<_Up>::value>
276struct __tuple_convertible
277    : public false_type {};
278
279template <class _Tp, class _Up>
280struct __tuple_convertible<_Tp, _Up, true, true>
281    : public __tuple_convertible_apply<tuple_size<typename remove_reference<_Tp>::type>::value ==
282                                     tuple_size<_Up>::value, _Tp, _Up>
283{};
284
285// __tuple_constructible
286
287template <class, class>
288struct __tuple_constructible_imp : public false_type {};
289
290template <class _Tp0, class ..._Tp, class _Up0, class ..._Up>
291struct __tuple_constructible_imp<__tuple_types<_Tp0, _Tp...>, __tuple_types<_Up0, _Up...> >
292    : public integral_constant<bool,
293                               is_constructible<_Up0, _Tp0>::value &&
294                               __tuple_constructible_imp<__tuple_types<_Tp...>, __tuple_types<_Up...> >::value> {};
295
296template <>
297struct __tuple_constructible_imp<__tuple_types<>, __tuple_types<> >
298    : public true_type {};
299
300template <bool _SameSize, class, class>
301struct __tuple_constructible_apply : public false_type {};
302
303template <class _Tp, class _Up>
304struct __tuple_constructible_apply<true, _Tp, _Up>
305  : public __tuple_constructible_imp<
306      typename __make_tuple_types<_Tp>::type
307    , typename __make_tuple_types<_Up>::type
308    >
309{};
310
311template <class _Tp, class _Up, bool = __tuple_like<typename remove_reference<_Tp>::type>::value,
312                                bool = __tuple_like<_Up>::value>
313struct __tuple_constructible
314    : public false_type {};
315
316template <class _Tp, class _Up>
317struct __tuple_constructible<_Tp, _Up, true, true>
318    : public __tuple_constructible_apply<tuple_size<typename remove_reference<_Tp>::type>::value ==
319                                     tuple_size<_Up>::value, _Tp, _Up>
320{};
321
322// __tuple_assignable
323
324template <class, class>
325struct __tuple_assignable_imp : public false_type {};
326
327template <class _Tp0, class ..._Tp, class _Up0, class ..._Up>
328struct __tuple_assignable_imp<__tuple_types<_Tp0, _Tp...>, __tuple_types<_Up0, _Up...> >
329    : public integral_constant<bool,
330                               is_assignable<_Up0&, _Tp0>::value &&
331                               __tuple_assignable_imp<__tuple_types<_Tp...>, __tuple_types<_Up...> >::value> {};
332
333template <>
334struct __tuple_assignable_imp<__tuple_types<>, __tuple_types<> >
335    : public true_type {};
336
337template <bool, class, class>
338struct __tuple_assignable_apply : public false_type {};
339
340template <class _Tp, class _Up>
341struct __tuple_assignable_apply<true, _Tp, _Up>
342  : __tuple_assignable_imp<
343      typename __make_tuple_types<_Tp>::type
344    , typename __make_tuple_types<_Up>::type
345    >
346{};
347
348template <class _Tp, class _Up, bool = __tuple_like<typename remove_reference<_Tp>::type>::value,
349                                bool = __tuple_like<_Up>::value>
350struct __tuple_assignable
351    : public false_type {};
352
353template <class _Tp, class _Up>
354struct __tuple_assignable<_Tp, _Up, true, true>
355    : public __tuple_assignable_apply<tuple_size<typename remove_reference<_Tp>::type>::value ==
356                                    tuple_size<_Up>::value, _Tp, _Up>
357{};
358
359#endif  // _LIBCPP_HAS_NO_VARIADICS
360
361_LIBCPP_END_NAMESPACE_STD
362
363#endif  // _LIBCPP___TUPLE
364