1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef _LIBCPP___TYPE_TRAITS_IS_NOTHROW_CONVERTIBLE_H
10 #define _LIBCPP___TYPE_TRAITS_IS_NOTHROW_CONVERTIBLE_H
11 
12 #include <__config>
13 #include <__type_traits/conjunction.h>
14 #include <__type_traits/disjunction.h>
15 #include <__type_traits/integral_constant.h>
16 #include <__type_traits/is_convertible.h>
17 #include <__type_traits/is_void.h>
18 #include <__type_traits/lazy.h>
19 #include <__utility/declval.h>
20 
21 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
22 #  pragma GCC system_header
23 #endif
24 
25 _LIBCPP_BEGIN_NAMESPACE_STD
26 
27 #if _LIBCPP_STD_VER >= 20
28 
29 template <typename _Tp>
30 void __test_noexcept(_Tp) noexcept;
31 
32 template <typename _Fm, typename _To>
33 bool_constant<noexcept(_VSTD::__test_noexcept<_To>(std::declval<_Fm>()))> __is_nothrow_convertible_test();
34 
35 template <typename _Fm, typename _To>
36 struct __is_nothrow_convertible_helper : decltype(__is_nothrow_convertible_test<_Fm, _To>()) {};
37 
38 template <typename _Fm, typename _To>
39 struct is_nothrow_convertible
40     : _Or<_And<is_void<_To>, is_void<_Fm>>,
41           _Lazy<_And, is_convertible<_Fm, _To>, __is_nothrow_convertible_helper<_Fm, _To> > >::type {};
42 
43 template <typename _Fm, typename _To>
44 inline constexpr bool is_nothrow_convertible_v = is_nothrow_convertible<_Fm, _To>::value;
45 
46 #endif // _LIBCPP_STD_VER >= 20
47 
48 _LIBCPP_END_NAMESPACE_STD
49 
50 #endif // _LIBCPP___TYPE_TRAITS_IS_NOTHROW_CONVERTIBLE_H
51