xref: /openbsd-src/gnu/llvm/libcxx/include/__tuple_dir/make_tuple_types.h (revision 4bdff4bed0e3d54e55670334c7d0077db4170f86)
1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef _LIBCPP___TUPLE_MAKE_TUPLE_TYPES_H
10 #define _LIBCPP___TUPLE_MAKE_TUPLE_TYPES_H
11 
12 #include <__config>
13 #include <__fwd/array.h>
14 #include <__fwd/tuple.h>
15 #include <__tuple_dir/apply_cv.h>
16 #include <__tuple_dir/tuple_element.h>
17 #include <__tuple_dir/tuple_indices.h>
18 #include <__tuple_dir/tuple_size.h>
19 #include <__tuple_dir/tuple_types.h>
20 #include <__type_traits/remove_cv.h>
21 #include <__type_traits/remove_reference.h>
22 #include <cstddef>
23 
24 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
25 #  pragma GCC system_header
26 #endif
27 
28 #ifndef _LIBCPP_CXX03_LANG
29 
30 _LIBCPP_BEGIN_NAMESPACE_STD
31 
32 // __make_tuple_types<_Tuple<_Types...>, _Ep, _Sp>::type is a
33 // __tuple_types<_Types...> using only those _Types in the range [_Sp, _Ep).
34 // _Sp defaults to 0 and _Ep defaults to tuple_size<_Tuple>.  If _Tuple is a
35 // lvalue_reference type, then __tuple_types<_Types&...> is the result.
36 
37 template <class _TupleTypes, class _TupleIndices>
38 struct __make_tuple_types_flat;
39 
40 template <template <class...> class _Tuple, class ..._Types, size_t ..._Idx>
41 struct __make_tuple_types_flat<_Tuple<_Types...>, __tuple_indices<_Idx...>> {
42   // Specialization for pair, tuple, and __tuple_types
43   template <class _Tp, class _ApplyFn = __apply_cv_t<_Tp>>
44   using __apply_quals _LIBCPP_NODEBUG = __tuple_types<
45       typename _ApplyFn::template __apply<__type_pack_element<_Idx, _Types...>>...
46     >;
47 };
48 
49 template <class _Vt, size_t _Np, size_t ..._Idx>
50 struct __make_tuple_types_flat<array<_Vt, _Np>, __tuple_indices<_Idx...>> {
51   template <size_t>
52   using __value_type = _Vt;
53   template <class _Tp, class _ApplyFn = __apply_cv_t<_Tp>>
54   using __apply_quals = __tuple_types<
55       typename _ApplyFn::template __apply<__value_type<_Idx>>...
56     >;
57 };
58 
59 template <class _Tp, size_t _Ep = tuple_size<__libcpp_remove_reference_t<_Tp> >::value,
60           size_t _Sp = 0,
61           bool _SameSize = (_Ep == tuple_size<__libcpp_remove_reference_t<_Tp> >::value)>
62 struct __make_tuple_types
63 {
64     static_assert(_Sp <= _Ep, "__make_tuple_types input error");
65     using _RawTp = __remove_cv_t<__libcpp_remove_reference_t<_Tp> >;
66     using _Maker = __make_tuple_types_flat<_RawTp, typename __make_tuple_indices<_Ep, _Sp>::type>;
67     using type = typename _Maker::template __apply_quals<_Tp>;
68 };
69 
70 template <class ..._Types, size_t _Ep>
71 struct __make_tuple_types<tuple<_Types...>, _Ep, 0, true> {
72   typedef _LIBCPP_NODEBUG __tuple_types<_Types...> type;
73 };
74 
75 template <class ..._Types, size_t _Ep>
76 struct __make_tuple_types<__tuple_types<_Types...>, _Ep, 0, true> {
77   typedef _LIBCPP_NODEBUG __tuple_types<_Types...> type;
78 };
79 
80 _LIBCPP_END_NAMESPACE_STD
81 
82 #endif // _LIBCPP_CXX03_LANG
83 
84 #endif // _LIBCPP___TUPLE_MAKE_TUPLE_TYPES_H
85