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1// -*- C++ -*-2//===----------------------------------------------------------------------===//3//4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.5// See https://llvm.org/LICENSE.txt for license information.6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception7//8//===----------------------------------------------------------------------===//9 10#ifndef _LIBCPP___ITERATOR_SIZE_H11#define _LIBCPP___ITERATOR_SIZE_H12 13#include <__config>14#include <__cstddef/ptrdiff_t.h>15#include <__cstddef/size_t.h>16#include <__type_traits/common_type.h>17#include <__type_traits/make_signed.h>18 19#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)20# pragma GCC system_header21#endif22 23_LIBCPP_BEGIN_NAMESPACE_STD24 25#if _LIBCPP_STD_VER >= 1726 27template <class _Cont>28_LIBCPP_HIDE_FROM_ABI constexpr auto size(const _Cont& __c) noexcept(noexcept(__c.size())) -> decltype(__c.size()) {29 return __c.size();30}31 32template <class _Tp, size_t _Sz>33_LIBCPP_HIDE_FROM_ABI constexpr size_t size(const _Tp (&)[_Sz]) noexcept {34 return _Sz;35}36 37# if _LIBCPP_STD_VER >= 2038template <class _Cont>39_LIBCPP_HIDE_FROM_ABI constexpr auto40ssize(const _Cont& __c) noexcept(noexcept(static_cast<common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>>>(41 __c.size()))) -> common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>> {42 return static_cast<common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>>>(__c.size());43}44 45// GCC complains about the implicit conversion from ptrdiff_t to size_t in46// the array bound.47_LIBCPP_DIAGNOSTIC_PUSH48_LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wsign-conversion")49template <class _Tp, ptrdiff_t _Sz>50_LIBCPP_HIDE_FROM_ABI constexpr ptrdiff_t ssize(const _Tp (&)[_Sz]) noexcept {51 return _Sz;52}53_LIBCPP_DIAGNOSTIC_POP54# endif55 56#endif // _LIBCPP_STD_VER >= 1757 58_LIBCPP_END_NAMESPACE_STD59 60#endif // _LIBCPP___ITERATOR_SIZE_H61