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 // <optional> 12 13 // template <class T> constexpr bool operator==(const optional<T>& x, const optional<T>& y); 14 15 #include <optional> 16 #include <type_traits> 17 #include <cassert> 18 19 using std::optional; 20 21 struct X 22 { 23 int i_; 24 25 constexpr X(int i) : i_(i) {} 26 }; 27 28 constexpr bool operator == ( const X &lhs, const X &rhs ) 29 { return lhs.i_ == rhs.i_ ; } 30 31 int main() 32 { 33 { 34 typedef X T; 35 typedef optional<T> O; 36 37 constexpr O o1; // disengaged 38 constexpr O o2; // disengaged 39 constexpr O o3{1}; // engaged 40 constexpr O o4{2}; // engaged 41 constexpr O o5{1}; // engaged 42 43 static_assert ( o1 == o1 , "" ); 44 static_assert ( o1 == o2 , "" ); 45 static_assert ( !(o1 == o3), "" ); 46 static_assert ( !(o1 == o4), "" ); 47 static_assert ( !(o1 == o5), "" ); 48 49 static_assert ( o2 == o1 , "" ); 50 static_assert ( o2 == o2 , "" ); 51 static_assert ( !(o2 == o3), "" ); 52 static_assert ( !(o2 == o4), "" ); 53 static_assert ( !(o2 == o5), "" ); 54 55 static_assert ( !(o3 == o1), "" ); 56 static_assert ( !(o3 == o2), "" ); 57 static_assert ( o3 == o3 , "" ); 58 static_assert ( !(o3 == o4), "" ); 59 static_assert ( o3 == o5 , "" ); 60 61 static_assert ( !(o4 == o1), "" ); 62 static_assert ( !(o4 == o2), "" ); 63 static_assert ( !(o4 == o3), "" ); 64 static_assert ( o4 == o4 , "" ); 65 static_assert ( !(o4 == o5), "" ); 66 67 static_assert ( !(o5 == o1), "" ); 68 static_assert ( !(o5 == o2), "" ); 69 static_assert ( o5 == o3 , "" ); 70 static_assert ( !(o5 == o4), "" ); 71 static_assert ( o5 == o5 , "" ); 72 73 } 74 } 75