| //===----------------------------------------------------------------------===// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| |
| // UNSUPPORTED: c++03, c++11, c++14, c++17 |
| |
| // template<class LHS, class RHS> |
| // concept assignable_from = |
| // std::is_lvalue_reference_v<LHS> && |
| // std::common_reference_with< |
| // const std::remove_reference_t<LHS>&, |
| // const std::remove_reference_t<RHS>&> && |
| // requires (LHS lhs, RHS&& rhs) { |
| // { lhs = std::forward<RHS>(rhs) } -> std::same_as<LHS>; |
| // }; |
| |
| #include <concepts> |
| #include <type_traits> |
| |
| #include "MoveOnly.h" |
| |
| struct NoCommonRef { |
| NoCommonRef& operator=(const int&); |
| }; |
| static_assert(std::is_assignable_v<NoCommonRef&, const int&>); |
| static_assert(!std::assignable_from<NoCommonRef&, const int&>); // no common reference type |
| |
| struct Base {}; |
| struct Derived : Base {}; |
| static_assert(!std::assignable_from<Base*, Derived*>); |
| static_assert( std::assignable_from<Base*&, Derived*>); |
| static_assert( std::assignable_from<Base*&, Derived*&>); |
| static_assert( std::assignable_from<Base*&, Derived*&&>); |
| static_assert( std::assignable_from<Base*&, Derived* const>); |
| static_assert( std::assignable_from<Base*&, Derived* const&>); |
| static_assert( std::assignable_from<Base*&, Derived* const&&>); |
| static_assert(!std::assignable_from<Base*&, const Derived*>); |
| static_assert(!std::assignable_from<Base*&, const Derived*&>); |
| static_assert(!std::assignable_from<Base*&, const Derived*&&>); |
| static_assert(!std::assignable_from<Base*&, const Derived* const>); |
| static_assert(!std::assignable_from<Base*&, const Derived* const&>); |
| static_assert(!std::assignable_from<Base*&, const Derived* const&&>); |
| static_assert( std::assignable_from<const Base*&, Derived*>); |
| static_assert( std::assignable_from<const Base*&, Derived*&>); |
| static_assert( std::assignable_from<const Base*&, Derived*&&>); |
| static_assert( std::assignable_from<const Base*&, Derived* const>); |
| static_assert( std::assignable_from<const Base*&, Derived* const&>); |
| static_assert( std::assignable_from<const Base*&, Derived* const&&>); |
| static_assert( std::assignable_from<const Base*&, const Derived*>); |
| static_assert( std::assignable_from<const Base*&, const Derived*&>); |
| static_assert( std::assignable_from<const Base*&, const Derived*&&>); |
| static_assert( std::assignable_from<const Base*&, const Derived* const>); |
| static_assert( std::assignable_from<const Base*&, const Derived* const&>); |
| static_assert( std::assignable_from<const Base*&, const Derived* const&&>); |
| |
| struct VoidResultType { |
| void operator=(const VoidResultType&); |
| }; |
| static_assert(std::is_assignable_v<VoidResultType&, const VoidResultType&>); |
| static_assert(!std::assignable_from<VoidResultType&, const VoidResultType&>); |
| |
| struct ValueResultType { |
| ValueResultType operator=(const ValueResultType&); |
| }; |
| static_assert(std::is_assignable_v<ValueResultType&, const ValueResultType&>); |
| static_assert(!std::assignable_from<ValueResultType&, const ValueResultType&>); |
| |
| struct Locale { |
| const Locale& operator=(const Locale&); |
| }; |
| static_assert(std::is_assignable_v<Locale&, const Locale&>); |
| static_assert(!std::assignable_from<Locale&, const Locale&>); |
| |
| struct Tuple { |
| Tuple& operator=(const Tuple&); |
| const Tuple& operator=(const Tuple&) const; |
| }; |
| static_assert(!std::assignable_from<Tuple, const Tuple&>); |
| static_assert( std::assignable_from<Tuple&, const Tuple&>); |
| static_assert(!std::assignable_from<Tuple&&, const Tuple&>); |
| static_assert(!std::assignable_from<const Tuple, const Tuple&>); |
| static_assert( std::assignable_from<const Tuple&, const Tuple&>); |
| static_assert(!std::assignable_from<const Tuple&&, const Tuple&>); |
| |
| // Finally, check a few simple cases. |
| static_assert( std::assignable_from<int&, int>); |
| static_assert( std::assignable_from<int&, int&>); |
| static_assert( std::assignable_from<int&, int&&>); |
| static_assert(!std::assignable_from<const int&, int>); |
| static_assert(!std::assignable_from<const int&, int&>); |
| static_assert(!std::assignable_from<const int&, int&&>); |
| static_assert( std::assignable_from<volatile int&, int>); |
| static_assert( std::assignable_from<volatile int&, int&>); |
| static_assert( std::assignable_from<volatile int&, int&&>); |
| static_assert(!std::assignable_from<int(&)[10], int>); |
| static_assert(!std::assignable_from<int(&)[10], int(&)[10]>); |
| static_assert( std::assignable_from<MoveOnly&, MoveOnly>); |
| static_assert(!std::assignable_from<MoveOnly&, MoveOnly&>); |
| static_assert( std::assignable_from<MoveOnly&, MoveOnly&&>); |
| static_assert(!std::assignable_from<void, int>); |
| static_assert(!std::assignable_from<void, void>); |