- 01
- 02
- 03
- 04
- 05
- 06
- 07
- 08
- 09
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 25
- 26
- 27
- 28
- 29
- 30
- 31
- 32
- 33
- 34
- 35
- 36
- 37
- 38
- 39
#if !__has_builtin(__make_integer_seq) || defined(_LIBCPP_TESTING_FALLBACK_MAKE_INTEGER_SEQUENCE)
namespace __detail {
template<typename _Tp, size_t ..._Extra> struct __repeat;
template<typename _Tp, _Tp ..._Np, size_t ..._Extra> struct __repeat<__integer_sequence<_Tp, _Np...>, _Extra...> {
typedef __integer_sequence<_Tp,
_Np...,
sizeof...(_Np) + _Np...,
2 * sizeof...(_Np) + _Np...,
3 * sizeof...(_Np) + _Np...,
4 * sizeof...(_Np) + _Np...,
5 * sizeof...(_Np) + _Np...,
6 * sizeof...(_Np) + _Np...,
7 * sizeof...(_Np) + _Np...,
_Extra...> type;
};
template<size_t _Np> struct __parity;
template<size_t _Np> struct __make : __parity<_Np % 8>::template __pmake<_Np> {};
template<> struct __make<0> { typedef __integer_sequence<size_t> type; };
template<> struct __make<1> { typedef __integer_sequence<size_t, 0> type; };
template<> struct __make<2> { typedef __integer_sequence<size_t, 0, 1> type; };
template<> struct __make<3> { typedef __integer_sequence<size_t, 0, 1, 2> type; };
template<> struct __make<4> { typedef __integer_sequence<size_t, 0, 1, 2, 3> type; };
template<> struct __make<5> { typedef __integer_sequence<size_t, 0, 1, 2, 3, 4> type; };
template<> struct __make<6> { typedef __integer_sequence<size_t, 0, 1, 2, 3, 4, 5> type; };
template<> struct __make<7> { typedef __integer_sequence<size_t, 0, 1, 2, 3, 4, 5, 6> type; };
template<> struct __parity<0> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type> {}; };
template<> struct __parity<1> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 1> {}; };
template<> struct __parity<2> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 2, _Np - 1> {}; };
template<> struct __parity<3> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 3, _Np - 2, _Np - 1> {}; };
template<> struct __parity<4> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 4, _Np - 3, _Np - 2, _Np - 1> {}; };
template<> struct __parity<5> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 5, _Np - 4, _Np - 3, _Np - 2, _Np - 1> {}; };
template<> struct __parity<6> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 6, _Np - 5, _Np - 4, _Np - 3, _Np - 2, _Np - 1> {}; };
template<> struct __parity<7> { template<size_t _Np> struct __pmake : __repeat<typename __make<_Np / 8>::type, _Np - 7, _Np - 6, _Np - 5, _Np - 4, _Np - 3, _Np - 2, _Np - 1> {}; };
} // namespace detail
Накопипащенная параша из стандартной библиотеки плюсов для clang/llvm, имеющая отношение к реализации integer_sequence и tuple
https://github.com/llvm-mirror/libcxx/blob/191f075c6fe7440659781f2603088b2df337c06a/include/__tuple#L101-L139
https://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20160627/163531.html