forked from OSchip/llvm-project
79 lines
2.5 KiB
C++
79 lines
2.5 KiB
C++
//===----------------------------------------------------------------------===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef _LIBCPP___UTILITY_INTEGER_SEQUENCE_H
|
|
#define _LIBCPP___UTILITY_INTEGER_SEQUENCE_H
|
|
|
|
#include <__config>
|
|
#include <type_traits>
|
|
|
|
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
|
|
#pragma GCC system_header
|
|
#endif
|
|
|
|
_LIBCPP_BEGIN_NAMESPACE_STD
|
|
|
|
#if _LIBCPP_STD_VER > 11
|
|
|
|
template<class _Tp, _Tp... _Ip>
|
|
struct _LIBCPP_TEMPLATE_VIS integer_sequence
|
|
{
|
|
typedef _Tp value_type;
|
|
static_assert( is_integral<_Tp>::value,
|
|
"std::integer_sequence can only be instantiated with an integral type" );
|
|
static
|
|
_LIBCPP_INLINE_VISIBILITY
|
|
constexpr
|
|
size_t
|
|
size() noexcept { return sizeof...(_Ip); }
|
|
};
|
|
|
|
template<size_t... _Ip>
|
|
using index_sequence = integer_sequence<size_t, _Ip...>;
|
|
|
|
#if __has_builtin(__make_integer_seq) && !defined(_LIBCPP_TESTING_FALLBACK_MAKE_INTEGER_SEQUENCE)
|
|
|
|
template <class _Tp, _Tp _Ep>
|
|
using __make_integer_sequence _LIBCPP_NODEBUG = __make_integer_seq<integer_sequence, _Tp, _Ep>;
|
|
|
|
#else
|
|
|
|
template<typename _Tp, _Tp _Np> using __make_integer_sequence_unchecked _LIBCPP_NODEBUG =
|
|
typename __detail::__make<_Np>::type::template __convert<integer_sequence, _Tp>;
|
|
|
|
template <class _Tp, _Tp _Ep>
|
|
struct __make_integer_sequence_checked
|
|
{
|
|
static_assert(is_integral<_Tp>::value,
|
|
"std::make_integer_sequence can only be instantiated with an integral type" );
|
|
static_assert(0 <= _Ep, "std::make_integer_sequence must have a non-negative sequence length");
|
|
// Workaround GCC bug by preventing bad installations when 0 <= _Ep
|
|
// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68929
|
|
typedef _LIBCPP_NODEBUG __make_integer_sequence_unchecked<_Tp, 0 <= _Ep ? _Ep : 0> type;
|
|
};
|
|
|
|
template <class _Tp, _Tp _Ep>
|
|
using __make_integer_sequence _LIBCPP_NODEBUG = typename __make_integer_sequence_checked<_Tp, _Ep>::type;
|
|
|
|
#endif
|
|
|
|
template<class _Tp, _Tp _Np>
|
|
using make_integer_sequence = __make_integer_sequence<_Tp, _Np>;
|
|
|
|
template<size_t _Np>
|
|
using make_index_sequence = make_integer_sequence<size_t, _Np>;
|
|
|
|
template<class... _Tp>
|
|
using index_sequence_for = make_index_sequence<sizeof...(_Tp)>;
|
|
|
|
#endif // _LIBCPP_STD_VER > 11
|
|
|
|
_LIBCPP_END_NAMESPACE_STD
|
|
|
|
#endif // _LIBCPP___UTILITY_INTEGER_SEQUENCE_H
|