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-exception 7 // 8 //===----------------------------------------------------------------------===// 9 10 #ifndef _LIBCPP___ITERATOR_SIZE_H 11 #define _LIBCPP___ITERATOR_SIZE_H 12 13 #include <__config> 14 #include <__type_traits/common_type.h> 15 #include <__type_traits/make_signed.h> 16 #include <cstddef> 17 18 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 19 # pragma GCC system_header 20 #endif 21 22 _LIBCPP_BEGIN_NAMESPACE_STD 23 24 #if _LIBCPP_STD_VER >= 17 25 26 template <class _Cont> 27 _LIBCPP_HIDE_FROM_ABI constexpr auto size(const _Cont& __c) noexcept(noexcept(__c.size())) -> decltype(__c.size()) { 28 return __c.size(); 29 } 30 31 template <class _Tp, size_t _Sz> size(const _Tp (&)[_Sz])32_LIBCPP_HIDE_FROM_ABI constexpr size_t size(const _Tp (&)[_Sz]) noexcept { 33 return _Sz; 34 } 35 36 # if _LIBCPP_STD_VER >= 20 37 template <class _Cont> 38 _LIBCPP_HIDE_FROM_ABI constexpr auto 39 ssize(const _Cont& __c) noexcept(noexcept(static_cast<common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>>>( 40 __c.size()))) -> common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>> { 41 return static_cast<common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>>>(__c.size()); 42 } 43 44 // GCC complains about the implicit conversion from ptrdiff_t to size_t in 45 // the array bound. 46 _LIBCPP_DIAGNOSTIC_PUSH 47 _LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wsign-conversion") 48 template <class _Tp, ptrdiff_t _Sz> ssize(const _Tp (&)[_Sz])49_LIBCPP_HIDE_FROM_ABI constexpr ptrdiff_t ssize(const _Tp (&)[_Sz]) noexcept { 50 return _Sz; 51 } 52 _LIBCPP_DIAGNOSTIC_POP 53 # endif 54 55 #endif // _LIBCPP_STD_VER >= 17 56 57 _LIBCPP_END_NAMESPACE_STD 58 59 #endif // _LIBCPP___ITERATOR_SIZE_H 60