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_EMPTY_H 11 #define _LIBCPP___ITERATOR_EMPTY_H 12 13 #include <__config> 14 #include <cstddef> 15 #include <initializer_list> 16 17 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 18 #pragma GCC system_header 19 #endif 20 21 _LIBCPP_PUSH_MACROS 22 #include <__undef_macros> 23 24 _LIBCPP_BEGIN_NAMESPACE_STD 25 26 #if _LIBCPP_STD_VER > 14 27 28 template <class _Cont> 29 _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY 30 constexpr auto empty(const _Cont& __c) 31 _NOEXCEPT_(noexcept(__c.empty())) 32 -> decltype (__c.empty()) 33 { return __c.empty(); } 34 35 template <class _Tp, size_t _Sz> 36 _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY 37 constexpr bool empty(const _Tp (&)[_Sz]) noexcept { return false; } 38 39 template <class _Ep> 40 _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY 41 constexpr bool empty(initializer_list<_Ep> __il) noexcept { return __il.size() == 0; } 42 43 #endif // _LIBCPP_STD_VER > 14 44 45 _LIBCPP_END_NAMESPACE_STD 46 47 _LIBCPP_POP_MACROS 48 49 #endif // _LIBCPP___ITERATOR_EMPTY_H 50