1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // <utility> 11 12 // template<ValueType T, size_t N> 13 // requires Swappable<T> 14 // void 15 // swap(T (&a)[N], T (&b)[N]); 16 17 #include <utility> 18 #include <cassert> 19 #include <memory> 20 21 #include "test_macros.h" 22 23 24 #if TEST_STD_VER >= 11 25 struct CopyOnly { 26 CopyOnly() {} 27 CopyOnly(CopyOnly const&) noexcept {} 28 CopyOnly& operator=(CopyOnly const&) { return *this; } 29 }; 30 31 32 struct NoexceptMoveOnly { 33 NoexceptMoveOnly() {} 34 NoexceptMoveOnly(NoexceptMoveOnly&&) noexcept {} 35 NoexceptMoveOnly& operator=(NoexceptMoveOnly&&) noexcept { return *this; } 36 }; 37 38 struct NotMoveConstructible { 39 NotMoveConstructible() {} 40 NotMoveConstructible& operator=(NotMoveConstructible&&) { return *this; } 41 private: 42 NotMoveConstructible(NotMoveConstructible&&); 43 }; 44 45 template <class Tp> 46 auto can_swap_test(int) -> decltype(std::swap(std::declval<Tp>(), std::declval<Tp>())); 47 48 template <class Tp> 49 auto can_swap_test(...) -> std::false_type; 50 51 template <class Tp> 52 constexpr bool can_swap() { 53 return std::is_same<decltype(can_swap_test<Tp>(0)), void>::value; 54 } 55 #endif 56 57 58 int main() 59 { 60 { 61 int i[3] = {1, 2, 3}; 62 int j[3] = {4, 5, 6}; 63 std::swap(i, j); 64 assert(i[0] == 4); 65 assert(i[1] == 5); 66 assert(i[2] == 6); 67 assert(j[0] == 1); 68 assert(j[1] == 2); 69 assert(j[2] == 3); 70 } 71 #if TEST_STD_VER >= 11 72 { 73 std::unique_ptr<int> i[3]; 74 for (int k = 0; k < 3; ++k) 75 i[k].reset(new int(k+1)); 76 std::unique_ptr<int> j[3]; 77 for (int k = 0; k < 3; ++k) 78 j[k].reset(new int(k+4)); 79 std::swap(i, j); 80 assert(*i[0] == 4); 81 assert(*i[1] == 5); 82 assert(*i[2] == 6); 83 assert(*j[0] == 1); 84 assert(*j[1] == 2); 85 assert(*j[2] == 3); 86 } 87 { 88 using CA = CopyOnly[42]; 89 using MA = NoexceptMoveOnly[42]; 90 using NA = NotMoveConstructible[42]; 91 static_assert(can_swap<CA&>(), ""); 92 static_assert(can_swap<MA&>(), ""); 93 static_assert(!can_swap<NA&>(), ""); 94 95 CA ca; 96 MA ma; 97 static_assert(!noexcept(std::swap(ca, ca)), ""); 98 static_assert(noexcept(std::swap(ma, ma)), ""); 99 } 100 #endif 101 } 102
