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 // <optional> 11 12 // optional<T>& operator=(optional<T>&& rhs) 13 // noexcept(is_nothrow_move_assignable<T>::value && 14 // is_nothrow_move_constructible<T>::value); 15 16 #include <experimental/optional> 17 #include <type_traits> 18 #include <cassert> 19 20 #if _LIBCPP_STD_VER > 11 21 22 using std::experimental::optional; 23 24 struct X 25 { 26 static bool throw_now; 27 28 X() = default; 29 X(X&&) 30 { 31 if (throw_now) 32 throw 6; 33 } 34 X& operator=(X&&) noexcept 35 { 36 return *this; 37 } 38 }; 39 40 struct Y {}; 41 42 bool X::throw_now = false; 43 44 #endif // _LIBCPP_STD_VER > 11 45 46 int main() 47 { 48 #if _LIBCPP_STD_VER > 11 49 { 50 static_assert(std::is_nothrow_move_assignable<optional<int>>::value, ""); 51 optional<int> opt; 52 constexpr optional<int> opt2; 53 opt = std::move(opt2); 54 static_assert(static_cast<bool>(opt2) == false, ""); 55 assert(static_cast<bool>(opt) == static_cast<bool>(opt2)); 56 } 57 { 58 optional<int> opt; 59 constexpr optional<int> opt2(2); 60 opt = std::move(opt2); 61 static_assert(static_cast<bool>(opt2) == true, ""); 62 static_assert(*opt2 == 2, ""); 63 assert(static_cast<bool>(opt) == static_cast<bool>(opt2)); 64 assert(*opt == *opt2); 65 } 66 { 67 optional<int> opt(3); 68 constexpr optional<int> opt2; 69 opt = std::move(opt2); 70 static_assert(static_cast<bool>(opt2) == false, ""); 71 assert(static_cast<bool>(opt) == static_cast<bool>(opt2)); 72 } 73 { 74 optional<int> opt(3); 75 constexpr optional<int> opt2(2); 76 opt = std::move(opt2); 77 static_assert(static_cast<bool>(opt2) == true, ""); 78 static_assert(*opt2 == 2, ""); 79 assert(static_cast<bool>(opt) == static_cast<bool>(opt2)); 80 assert(*opt == *opt2); 81 } 82 { 83 static_assert(!std::is_nothrow_move_assignable<optional<X>>::value, ""); 84 optional<X> opt; 85 optional<X> opt2(X{}); 86 assert(static_cast<bool>(opt2) == true); 87 try 88 { 89 X::throw_now = true; 90 opt = std::move(opt2); 91 assert(false); 92 } 93 catch (int i) 94 { 95 assert(i == 6); 96 assert(static_cast<bool>(opt) == false); 97 } 98 } 99 { 100 static_assert(std::is_nothrow_move_assignable<optional<Y>>::value, ""); 101 } 102 #endif // _LIBCPP_STD_VER > 11 103 } 104
