1*fe6060f1SDimitry Andric // -*- C++ -*- 2*fe6060f1SDimitry Andric //===----------------------------------------------------------------------===// 3*fe6060f1SDimitry Andric // 4*fe6060f1SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5*fe6060f1SDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 6*fe6060f1SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7*fe6060f1SDimitry Andric // 8*fe6060f1SDimitry Andric //===----------------------------------------------------------------------===// 9*fe6060f1SDimitry Andric 10*fe6060f1SDimitry Andric #ifndef _LIBCPP___ITERATOR_NEXT_H 11*fe6060f1SDimitry Andric #define _LIBCPP___ITERATOR_NEXT_H 12*fe6060f1SDimitry Andric 13*fe6060f1SDimitry Andric #include <__config> 14*fe6060f1SDimitry Andric #include <__debug> 15*fe6060f1SDimitry Andric #include <__function_like.h> 16*fe6060f1SDimitry Andric #include <__iterator/advance.h> 17*fe6060f1SDimitry Andric #include <__iterator/concepts.h> 18*fe6060f1SDimitry Andric #include <__iterator/incrementable_traits.h> 19*fe6060f1SDimitry Andric #include <__iterator/iterator_traits.h> 20*fe6060f1SDimitry Andric #include <type_traits> 21*fe6060f1SDimitry Andric 22*fe6060f1SDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 23*fe6060f1SDimitry Andric #pragma GCC system_header 24*fe6060f1SDimitry Andric #endif 25*fe6060f1SDimitry Andric 26*fe6060f1SDimitry Andric _LIBCPP_PUSH_MACROS 27*fe6060f1SDimitry Andric #include <__undef_macros> 28*fe6060f1SDimitry Andric 29*fe6060f1SDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD 30*fe6060f1SDimitry Andric 31*fe6060f1SDimitry Andric template <class _InputIter> 32*fe6060f1SDimitry Andric inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 33*fe6060f1SDimitry Andric typename enable_if<__is_cpp17_input_iterator<_InputIter>::value, _InputIter>::type 34*fe6060f1SDimitry Andric next(_InputIter __x, typename iterator_traits<_InputIter>::difference_type __n = 1) { 35*fe6060f1SDimitry Andric _LIBCPP_ASSERT(__n >= 0 || __is_cpp17_bidirectional_iterator<_InputIter>::value, 36*fe6060f1SDimitry Andric "Attempt to next(it, n) with negative n on a non-bidirectional iterator"); 37*fe6060f1SDimitry Andric 38*fe6060f1SDimitry Andric _VSTD::advance(__x, __n); 39*fe6060f1SDimitry Andric return __x; 40*fe6060f1SDimitry Andric } 41*fe6060f1SDimitry Andric 42*fe6060f1SDimitry Andric #if !defined(_LIBCPP_HAS_NO_RANGES) 43*fe6060f1SDimitry Andric 44*fe6060f1SDimitry Andric namespace ranges { 45*fe6060f1SDimitry Andric struct __next_fn final : private __function_like { 46*fe6060f1SDimitry Andric _LIBCPP_HIDE_FROM_ABI 47*fe6060f1SDimitry Andric constexpr explicit __next_fn(__tag __x) noexcept : __function_like(__x) {} 48*fe6060f1SDimitry Andric 49*fe6060f1SDimitry Andric template <input_or_output_iterator _Ip> 50*fe6060f1SDimitry Andric _LIBCPP_HIDE_FROM_ABI 51*fe6060f1SDimitry Andric constexpr _Ip operator()(_Ip __x) const { 52*fe6060f1SDimitry Andric ++__x; 53*fe6060f1SDimitry Andric return __x; 54*fe6060f1SDimitry Andric } 55*fe6060f1SDimitry Andric 56*fe6060f1SDimitry Andric template <input_or_output_iterator _Ip> 57*fe6060f1SDimitry Andric _LIBCPP_HIDE_FROM_ABI 58*fe6060f1SDimitry Andric constexpr _Ip operator()(_Ip __x, iter_difference_t<_Ip> __n) const { 59*fe6060f1SDimitry Andric ranges::advance(__x, __n); 60*fe6060f1SDimitry Andric return __x; 61*fe6060f1SDimitry Andric } 62*fe6060f1SDimitry Andric 63*fe6060f1SDimitry Andric template <input_or_output_iterator _Ip, sentinel_for<_Ip> _Sp> 64*fe6060f1SDimitry Andric _LIBCPP_HIDE_FROM_ABI 65*fe6060f1SDimitry Andric constexpr _Ip operator()(_Ip __x, _Sp __bound) const { 66*fe6060f1SDimitry Andric ranges::advance(__x, __bound); 67*fe6060f1SDimitry Andric return __x; 68*fe6060f1SDimitry Andric } 69*fe6060f1SDimitry Andric 70*fe6060f1SDimitry Andric template <input_or_output_iterator _Ip, sentinel_for<_Ip> _Sp> 71*fe6060f1SDimitry Andric _LIBCPP_HIDE_FROM_ABI 72*fe6060f1SDimitry Andric constexpr _Ip operator()(_Ip __x, iter_difference_t<_Ip> __n, _Sp __bound) const { 73*fe6060f1SDimitry Andric ranges::advance(__x, __n, __bound); 74*fe6060f1SDimitry Andric return __x; 75*fe6060f1SDimitry Andric } 76*fe6060f1SDimitry Andric }; 77*fe6060f1SDimitry Andric 78*fe6060f1SDimitry Andric inline constexpr auto next = __next_fn(__function_like::__tag()); 79*fe6060f1SDimitry Andric } // namespace ranges 80*fe6060f1SDimitry Andric 81*fe6060f1SDimitry Andric #endif // !defined(_LIBCPP_HAS_NO_RANGES) 82*fe6060f1SDimitry Andric 83*fe6060f1SDimitry Andric _LIBCPP_END_NAMESPACE_STD 84*fe6060f1SDimitry Andric 85*fe6060f1SDimitry Andric _LIBCPP_POP_MACROS 86*fe6060f1SDimitry Andric 87*fe6060f1SDimitry Andric #endif // _LIBCPP___ITERATOR_PRIMITIVES_H 88