| //===----------------------------------------------------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is dual licensed under the MIT and the University of Illinois Open |
| // Source Licenses. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| // UNSUPPORTED: c++98, c++03, c++11, c++14 |
| |
| // type_traits |
| |
| // is_swappable |
| |
| #include <type_traits> |
| #include <utility> |
| #include <vector> |
| #include "test_macros.h" |
| |
| namespace MyNS { |
| |
| // Make the test types non-copyable so that generic std::swap is not valid. |
| struct A { |
| A(A const&) = delete; |
| A& operator=(A const&) = delete; |
| }; |
| |
| struct B { |
| B(B const&) = delete; |
| B& operator=(B const&) = delete; |
| }; |
| |
| struct C {}; |
| struct D {}; |
| |
| void swap(A&, A&) {} |
| |
| void swap(A&, B&) {} |
| void swap(B&, A&) {} |
| |
| void swap(A&, C&) {} // missing swap(C, A) |
| void swap(D&, C&) {} |
| |
| struct M { |
| M(M const&) = delete; |
| M& operator=(M const&) = delete; |
| }; |
| |
| void swap(M&&, M&&) {} |
| |
| } // namespace MyNS |
| |
| int main() |
| { |
| using namespace MyNS; |
| { |
| // Test that is_swappable applies an lvalue reference to the type. |
| static_assert(std::is_swappable<A>::value, ""); |
| static_assert(std::is_swappable<A&>::value, ""); |
| static_assert(!std::is_swappable<M>::value, ""); |
| static_assert(!std::is_swappable<M&&>::value, ""); |
| } |
| static_assert(!std::is_swappable<B>::value, ""); |
| static_assert(std::is_swappable<C>::value, ""); |
| { |
| // test non-referencable types |
| static_assert(!std::is_swappable<void>::value, ""); |
| static_assert(!std::is_swappable<int() const>::value, ""); |
| static_assert(!std::is_swappable<int() &>::value, ""); |
| } |
| { |
| // test for presense of is_swappable_v |
| static_assert(std::is_swappable_v<int>); |
| static_assert(!std::is_swappable_v<M>); |
| } |
| } |