xref: /freebsd-src/contrib/llvm-project/libcxx/include/__iterator/size.h (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
1fe6060f1SDimitry Andric // -*- C++ -*-
2fe6060f1SDimitry Andric //===----------------------------------------------------------------------===//
3fe6060f1SDimitry Andric //
4fe6060f1SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5fe6060f1SDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
6fe6060f1SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7fe6060f1SDimitry Andric //
8fe6060f1SDimitry Andric //===----------------------------------------------------------------------===//
9fe6060f1SDimitry Andric 
10fe6060f1SDimitry Andric #ifndef _LIBCPP___ITERATOR_SIZE_H
11fe6060f1SDimitry Andric #define _LIBCPP___ITERATOR_SIZE_H
12fe6060f1SDimitry Andric 
13fe6060f1SDimitry Andric #include <__config>
14bdd1243dSDimitry Andric #include <__type_traits/common_type.h>
15bdd1243dSDimitry Andric #include <__type_traits/make_signed.h>
16fe6060f1SDimitry Andric #include <cstddef>
17fe6060f1SDimitry Andric 
18fe6060f1SDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
19fe6060f1SDimitry Andric #  pragma GCC system_header
20fe6060f1SDimitry Andric #endif
21fe6060f1SDimitry Andric 
22fe6060f1SDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD
23fe6060f1SDimitry Andric 
2406c3fb27SDimitry Andric #if _LIBCPP_STD_VER >= 17
25fe6060f1SDimitry Andric 
26fe6060f1SDimitry Andric template <class _Cont>
27*0fca6ea1SDimitry Andric _LIBCPP_HIDE_FROM_ABI constexpr auto size(const _Cont& __c) noexcept(noexcept(__c.size())) -> decltype(__c.size()) {
28cb14a3feSDimitry Andric   return __c.size();
29cb14a3feSDimitry Andric }
30fe6060f1SDimitry Andric 
31fe6060f1SDimitry Andric template <class _Tp, size_t _Sz>
32cb14a3feSDimitry Andric _LIBCPP_HIDE_FROM_ABI constexpr size_t size(const _Tp (&)[_Sz]) noexcept {
33cb14a3feSDimitry Andric   return _Sz;
34cb14a3feSDimitry Andric }
35fe6060f1SDimitry Andric 
3606c3fb27SDimitry Andric #  if _LIBCPP_STD_VER >= 20
37fe6060f1SDimitry Andric template <class _Cont>
38*0fca6ea1SDimitry Andric _LIBCPP_HIDE_FROM_ABI constexpr auto
39*0fca6ea1SDimitry Andric ssize(const _Cont& __c) noexcept(noexcept(static_cast<common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>>>(
40*0fca6ea1SDimitry Andric     __c.size()))) -> common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>> {
41cb14a3feSDimitry Andric   return static_cast<common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>>>(__c.size());
42cb14a3feSDimitry Andric }
43fe6060f1SDimitry Andric 
4481ad6265SDimitry Andric // GCC complains about the implicit conversion from ptrdiff_t to size_t in
4581ad6265SDimitry Andric // the array bound.
4681ad6265SDimitry Andric _LIBCPP_DIAGNOSTIC_PUSH
4781ad6265SDimitry Andric _LIBCPP_GCC_DIAGNOSTIC_IGNORED("-Wsign-conversion")
48fe6060f1SDimitry Andric template <class _Tp, ptrdiff_t _Sz>
49cb14a3feSDimitry Andric _LIBCPP_HIDE_FROM_ABI constexpr ptrdiff_t ssize(const _Tp (&)[_Sz]) noexcept {
50cb14a3feSDimitry Andric   return _Sz;
51cb14a3feSDimitry Andric }
5281ad6265SDimitry Andric _LIBCPP_DIAGNOSTIC_POP
53fe6060f1SDimitry Andric #  endif
54fe6060f1SDimitry Andric 
5506c3fb27SDimitry Andric #endif // _LIBCPP_STD_VER >= 17
56fe6060f1SDimitry Andric 
57fe6060f1SDimitry Andric _LIBCPP_END_NAMESPACE_STD
58fe6060f1SDimitry Andric 
59fe6060f1SDimitry Andric #endif // _LIBCPP___ITERATOR_SIZE_H
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