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