diff options
Diffstat (limited to 'libcxx/include/__tuple_dir/sfinae_helpers.h')
| -rw-r--r-- | libcxx/include/__tuple_dir/sfinae_helpers.h | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/libcxx/include/__tuple_dir/sfinae_helpers.h b/libcxx/include/__tuple_dir/sfinae_helpers.h new file mode 100644 index 000000000000..fcd65a0817be --- /dev/null +++ b/libcxx/include/__tuple_dir/sfinae_helpers.h @@ -0,0 +1,196 @@ +//===----------------------------------------------------------------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#ifndef _LIBCPP___TUPLE_SFINAE_HELPERS_H +#define _LIBCPP___TUPLE_SFINAE_HELPERS_H + +#include <__config> +#include <__fwd/tuple.h> +#include <__tuple_dir/make_tuple_types.h> +#include <__tuple_dir/tuple_element.h> +#include <__tuple_dir/tuple_like_ext.h> +#include <__tuple_dir/tuple_size.h> +#include <__tuple_dir/tuple_types.h> +#include <__type_traits/enable_if.h> +#include <__type_traits/integral_constant.h> +#include <__type_traits/is_assignable.h> +#include <__type_traits/is_constructible.h> +#include <__type_traits/is_convertible.h> +#include <__type_traits/is_same.h> +#include <__type_traits/remove_cvref.h> +#include <__type_traits/remove_reference.h> +#include <cstddef> + +#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) +# pragma GCC system_header +#endif + +_LIBCPP_BEGIN_NAMESPACE_STD + +#ifndef _LIBCPP_CXX03_LANG + +template <bool ..._Preds> +struct __all_dummy; + +template <bool ..._Pred> +struct __all : _IsSame<__all_dummy<_Pred...>, __all_dummy<((void)_Pred, true)...>> {}; + +struct __tuple_sfinae_base { + template <template <class, class...> class _Trait, + class ..._LArgs, class ..._RArgs> + static auto __do_test(__tuple_types<_LArgs...>, __tuple_types<_RArgs...>) + -> __all<__enable_if_t<_Trait<_LArgs, _RArgs>::value, bool>{true}...>; + template <template <class...> class> + static auto __do_test(...) -> false_type; + + template <class _FromArgs, class _ToArgs> + using __constructible = decltype(__do_test<is_constructible>(_ToArgs{}, _FromArgs{})); + template <class _FromArgs, class _ToArgs> + using __convertible = decltype(__do_test<is_convertible>(_FromArgs{}, _ToArgs{})); + template <class _FromArgs, class _ToArgs> + using __assignable = decltype(__do_test<is_assignable>(_ToArgs{}, _FromArgs{})); +}; + +// __tuple_convertible + +template <class _Tp, class _Up, bool = __tuple_like_ext<__libcpp_remove_reference_t<_Tp> >::value, + bool = __tuple_like_ext<_Up>::value> +struct __tuple_convertible + : public false_type {}; + +template <class _Tp, class _Up> +struct __tuple_convertible<_Tp, _Up, true, true> + : public __tuple_sfinae_base::__convertible< + typename __make_tuple_types<_Tp>::type + , typename __make_tuple_types<_Up>::type + > +{}; + +// __tuple_constructible + +template <class _Tp, class _Up, bool = __tuple_like_ext<__libcpp_remove_reference_t<_Tp> >::value, + bool = __tuple_like_ext<_Up>::value> +struct __tuple_constructible + : public false_type {}; + +template <class _Tp, class _Up> +struct __tuple_constructible<_Tp, _Up, true, true> + : public __tuple_sfinae_base::__constructible< + typename __make_tuple_types<_Tp>::type + , typename __make_tuple_types<_Up>::type + > +{}; + +// __tuple_assignable + +template <class _Tp, class _Up, bool = __tuple_like_ext<__libcpp_remove_reference_t<_Tp> >::value, + bool = __tuple_like_ext<_Up>::value> +struct __tuple_assignable + : public false_type {}; + +template <class _Tp, class _Up> +struct __tuple_assignable<_Tp, _Up, true, true> + : public __tuple_sfinae_base::__assignable< + typename __make_tuple_types<_Tp>::type + , typename __make_tuple_types<_Up&>::type + > +{}; + + +template <size_t _Ip, class ..._Tp> +struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, tuple<_Tp...> > +{ + typedef _LIBCPP_NODEBUG typename tuple_element<_Ip, __tuple_types<_Tp...> >::type type; +}; + +template <bool _IsTuple, class _SizeTrait, size_t _Expected> +struct __tuple_like_with_size_imp : false_type {}; + +template <class _SizeTrait, size_t _Expected> +struct __tuple_like_with_size_imp<true, _SizeTrait, _Expected> + : integral_constant<bool, _SizeTrait::value == _Expected> {}; + +template <class _Tuple, size_t _ExpectedSize, class _RawTuple = __libcpp_remove_reference_t<_Tuple> > +using __tuple_like_with_size _LIBCPP_NODEBUG = __tuple_like_with_size_imp< + __tuple_like_ext<_RawTuple>::value, + tuple_size<_RawTuple>, _ExpectedSize + >; + +struct _LIBCPP_TYPE_VIS __check_tuple_constructor_fail { + + static constexpr bool __enable_explicit_default() { return false; } + static constexpr bool __enable_implicit_default() { return false; } + template <class ...> + static constexpr bool __enable_explicit() { return false; } + template <class ...> + static constexpr bool __enable_implicit() { return false; } + template <class ...> + static constexpr bool __enable_assign() { return false; } +}; +#endif // !defined(_LIBCPP_CXX03_LANG) + +#if _LIBCPP_STD_VER > 14 + +template <bool _CanCopy, bool _CanMove> +struct __sfinae_ctor_base {}; +template <> +struct __sfinae_ctor_base<false, false> { + __sfinae_ctor_base() = default; + __sfinae_ctor_base(__sfinae_ctor_base const&) = delete; + __sfinae_ctor_base(__sfinae_ctor_base &&) = delete; + __sfinae_ctor_base& operator=(__sfinae_ctor_base const&) = default; + __sfinae_ctor_base& operator=(__sfinae_ctor_base&&) = default; +}; +template <> +struct __sfinae_ctor_base<true, false> { + __sfinae_ctor_base() = default; + __sfinae_ctor_base(__sfinae_ctor_base const&) = default; + __sfinae_ctor_base(__sfinae_ctor_base &&) = delete; + __sfinae_ctor_base& operator=(__sfinae_ctor_base const&) = default; + __sfinae_ctor_base& operator=(__sfinae_ctor_base&&) = default; +}; +template <> +struct __sfinae_ctor_base<false, true> { + __sfinae_ctor_base() = default; + __sfinae_ctor_base(__sfinae_ctor_base const&) = delete; + __sfinae_ctor_base(__sfinae_ctor_base &&) = default; + __sfinae_ctor_base& operator=(__sfinae_ctor_base const&) = default; + __sfinae_ctor_base& operator=(__sfinae_ctor_base&&) = default; +}; + +template <bool _CanCopy, bool _CanMove> +struct __sfinae_assign_base {}; +template <> +struct __sfinae_assign_base<false, false> { + __sfinae_assign_base() = default; + __sfinae_assign_base(__sfinae_assign_base const&) = default; + __sfinae_assign_base(__sfinae_assign_base &&) = default; + __sfinae_assign_base& operator=(__sfinae_assign_base const&) = delete; + __sfinae_assign_base& operator=(__sfinae_assign_base&&) = delete; +}; +template <> +struct __sfinae_assign_base<true, false> { + __sfinae_assign_base() = default; + __sfinae_assign_base(__sfinae_assign_base const&) = default; + __sfinae_assign_base(__sfinae_assign_base &&) = default; + __sfinae_assign_base& operator=(__sfinae_assign_base const&) = default; + __sfinae_assign_base& operator=(__sfinae_assign_base&&) = delete; +}; +template <> +struct __sfinae_assign_base<false, true> { + __sfinae_assign_base() = default; + __sfinae_assign_base(__sfinae_assign_base const&) = default; + __sfinae_assign_base(__sfinae_assign_base &&) = default; + __sfinae_assign_base& operator=(__sfinae_assign_base const&) = delete; + __sfinae_assign_base& operator=(__sfinae_assign_base&&) = default; +}; +#endif // _LIBCPP_STD_VER > 14 + +_LIBCPP_END_NAMESPACE_STD + +#endif // _LIBCPP___TUPLE_SFINAE_HELPERS_H |