special_members.pass.cpp (2270B)
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 // UNSUPPORTED: c++98, c++03, c++11, c++14 11 12 // <optional> 13 14 // Make sure we properly generate special member functions for optional<T> 15 // based on the properties of T itself. 16 17 #include <optional> 18 #include <type_traits> 19 20 #include "archetypes.hpp" 21 22 23 template <class T> 24 struct SpecialMemberTest { 25 using O = std::optional<T>; 26 27 static_assert(std::is_default_constructible_v<O>, 28 "optional is always default constructible."); 29 30 static_assert(std::is_copy_constructible_v<O> == std::is_copy_constructible_v<T>, 31 "optional<T> is copy constructible if and only if T is copy constructible."); 32 33 static_assert(std::is_move_constructible_v<O> == 34 (std::is_copy_constructible_v<T> || std::is_move_constructible_v<T>), 35 "optional<T> is move constructible if and only if T is copy or move constructible."); 36 37 static_assert(std::is_copy_assignable_v<O> == 38 (std::is_copy_constructible_v<T> && std::is_copy_assignable_v<T>), 39 "optional<T> is copy assignable if and only if T is both copy " 40 "constructible and copy assignable."); 41 42 static_assert(std::is_move_assignable_v<O> == 43 ((std::is_move_constructible_v<T> && std::is_move_assignable_v<T>) || 44 (std::is_copy_constructible_v<T> && std::is_copy_assignable_v<T>)), 45 "optional<T> is move assignable if and only if T is both move constructible and " 46 "move assignable, or both copy constructible and copy assignable."); 47 }; 48 49 template <class ...Args> static void sink(Args&&...) {} 50 51 template <class ...TestTypes> 52 struct DoTestsMetafunction { 53 DoTestsMetafunction() { sink(SpecialMemberTest<TestTypes>{}...); } 54 }; 55 56 int main() { 57 sink( 58 ImplicitTypes::ApplyTypes<DoTestsMetafunction>{}, 59 ExplicitTypes::ApplyTypes<DoTestsMetafunction>{}, 60 NonLiteralTypes::ApplyTypes<DoTestsMetafunction>{}, 61 NonTrivialTypes::ApplyTypes<DoTestsMetafunction>{} 62 ); 63 }