xref: /freebsd-src/contrib/llvm-project/libcxx/include/__tuple/tuple_size.h (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
106c3fb27SDimitry Andric //===----------------------------------------------------------------------===//
206c3fb27SDimitry Andric //
306c3fb27SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
406c3fb27SDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
506c3fb27SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
606c3fb27SDimitry Andric //
706c3fb27SDimitry Andric //===----------------------------------------------------------------------===//
806c3fb27SDimitry Andric 
906c3fb27SDimitry Andric #ifndef _LIBCPP___TUPLE_TUPLE_SIZE_H
1006c3fb27SDimitry Andric #define _LIBCPP___TUPLE_TUPLE_SIZE_H
1106c3fb27SDimitry Andric 
1206c3fb27SDimitry Andric #include <__config>
1306c3fb27SDimitry Andric #include <__fwd/tuple.h>
1406c3fb27SDimitry Andric #include <__tuple/tuple_types.h>
1506c3fb27SDimitry Andric #include <__type_traits/is_const.h>
1606c3fb27SDimitry Andric #include <__type_traits/is_volatile.h>
1706c3fb27SDimitry Andric #include <cstddef>
1806c3fb27SDimitry Andric 
1906c3fb27SDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
2006c3fb27SDimitry Andric #  pragma GCC system_header
2106c3fb27SDimitry Andric #endif
2206c3fb27SDimitry Andric 
2306c3fb27SDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD
2406c3fb27SDimitry Andric 
25cb14a3feSDimitry Andric template <class _Tp>
26cb14a3feSDimitry Andric struct _LIBCPP_TEMPLATE_VIS tuple_size;
2706c3fb27SDimitry Andric 
2806c3fb27SDimitry Andric #if !defined(_LIBCPP_CXX03_LANG)
2906c3fb27SDimitry Andric template <class _Tp, class...>
3006c3fb27SDimitry Andric using __enable_if_tuple_size_imp = _Tp;
3106c3fb27SDimitry Andric 
3206c3fb27SDimitry Andric template <class _Tp>
33cb14a3feSDimitry Andric struct _LIBCPP_TEMPLATE_VIS tuple_size<__enable_if_tuple_size_imp< const _Tp,
3406c3fb27SDimitry Andric                                                                    __enable_if_t<!is_volatile<_Tp>::value>,
3506c3fb27SDimitry Andric                                                                    integral_constant<size_t, sizeof(tuple_size<_Tp>)>>>
3606c3fb27SDimitry Andric     : public integral_constant<size_t, tuple_size<_Tp>::value> {};
3706c3fb27SDimitry Andric 
3806c3fb27SDimitry Andric template <class _Tp>
39cb14a3feSDimitry Andric struct _LIBCPP_TEMPLATE_VIS tuple_size<__enable_if_tuple_size_imp< volatile _Tp,
4006c3fb27SDimitry Andric                                                                    __enable_if_t<!is_const<_Tp>::value>,
4106c3fb27SDimitry Andric                                                                    integral_constant<size_t, sizeof(tuple_size<_Tp>)>>>
4206c3fb27SDimitry Andric     : public integral_constant<size_t, tuple_size<_Tp>::value> {};
4306c3fb27SDimitry Andric 
4406c3fb27SDimitry Andric template <class _Tp>
45cb14a3feSDimitry Andric struct _LIBCPP_TEMPLATE_VIS
46cb14a3feSDimitry Andric tuple_size<__enable_if_tuple_size_imp<const volatile _Tp, integral_constant<size_t, sizeof(tuple_size<_Tp>)>>>
4706c3fb27SDimitry Andric     : public integral_constant<size_t, tuple_size<_Tp>::value> {};
4806c3fb27SDimitry Andric 
4906c3fb27SDimitry Andric #else
50cb14a3feSDimitry Andric template <class _Tp>
51cb14a3feSDimitry Andric struct _LIBCPP_TEMPLATE_VIS tuple_size<const _Tp> : public tuple_size<_Tp> {};
52cb14a3feSDimitry Andric template <class _Tp>
53cb14a3feSDimitry Andric struct _LIBCPP_TEMPLATE_VIS tuple_size<volatile _Tp> : public tuple_size<_Tp> {};
54cb14a3feSDimitry Andric template <class _Tp>
55cb14a3feSDimitry Andric struct _LIBCPP_TEMPLATE_VIS tuple_size<const volatile _Tp> : public tuple_size<_Tp> {};
5606c3fb27SDimitry Andric #endif
5706c3fb27SDimitry Andric 
5806c3fb27SDimitry Andric #ifndef _LIBCPP_CXX03_LANG
5906c3fb27SDimitry Andric 
6006c3fb27SDimitry Andric template <class... _Tp>
61cb14a3feSDimitry Andric struct _LIBCPP_TEMPLATE_VIS tuple_size<tuple<_Tp...> > : public integral_constant<size_t, sizeof...(_Tp)> {};
6206c3fb27SDimitry Andric 
6306c3fb27SDimitry Andric template <class... _Tp>
64cb14a3feSDimitry Andric struct _LIBCPP_TEMPLATE_VIS tuple_size<__tuple_types<_Tp...> > : public integral_constant<size_t, sizeof...(_Tp)> {};
65*0fca6ea1SDimitry Andric 
66*0fca6ea1SDimitry Andric #  if _LIBCPP_STD_VER >= 17
67*0fca6ea1SDimitry Andric template <class _Tp>
68*0fca6ea1SDimitry Andric inline constexpr size_t tuple_size_v = tuple_size<_Tp>::value;
69*0fca6ea1SDimitry Andric #  endif
7006c3fb27SDimitry Andric 
7106c3fb27SDimitry Andric #endif // _LIBCPP_CXX03_LANG
7206c3fb27SDimitry Andric 
7306c3fb27SDimitry Andric _LIBCPP_END_NAMESPACE_STD
7406c3fb27SDimitry Andric 
7506c3fb27SDimitry Andric #endif // _LIBCPP___TUPLE_TUPLE_SIZE_H
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