| // -*- 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___ITERATOR_DISTANCE_H | |
| #define _LIBCPP___ITERATOR_DISTANCE_H | |
| #include <__config> | |
| #include <__iterator/iterator_traits.h> | |
| #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) | |
| #pragma GCC system_header | |
| #endif | |
| _LIBCPP_PUSH_MACROS | |
| #include <__undef_macros> | |
| _LIBCPP_BEGIN_NAMESPACE_STD | |
| template <class _InputIter> | |
| inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 | |
| typename iterator_traits<_InputIter>::difference_type | |
| __distance(_InputIter __first, _InputIter __last, input_iterator_tag) | |
| { | |
| typename iterator_traits<_InputIter>::difference_type __r(0); | |
| for (; __first != __last; ++__first) | |
| ++__r; | |
| return __r; | |
| } | |
| template <class _RandIter> | |
| inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 | |
| typename iterator_traits<_RandIter>::difference_type | |
| __distance(_RandIter __first, _RandIter __last, random_access_iterator_tag) | |
| { | |
| return __last - __first; | |
| } | |
| template <class _InputIter> | |
| inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 | |
| typename iterator_traits<_InputIter>::difference_type | |
| distance(_InputIter __first, _InputIter __last) | |
| { | |
| return _VSTD::__distance(__first, __last, typename iterator_traits<_InputIter>::iterator_category()); | |
| } | |
| _LIBCPP_END_NAMESPACE_STD | |
| _LIBCPP_POP_MACROS | |
| #endif // _LIBCPP___ITERATOR_DISTANCE_H |