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 11 // <optional> 12 13 // template <class T> constexpr bool operator<=(const optional<T>& x, nullopt_t) noexcept; 14 // template <class T> constexpr bool operator<=(nullopt_t, const optional<T>& x) noexcept; 15 16 #include <experimental/optional> 17 18 #include "test_macros.h" 19 20 int main() 21 { 22 #if TEST_STD_VER > 11 23 using std::experimental::optional; 24 using std::experimental::nullopt_t; 25 using std::experimental::nullopt; 26 27 { 28 typedef int T; 29 typedef optional<T> O; 30 31 constexpr O o1; // disengaged 32 constexpr O o2{1}; // engaged 33 34 static_assert ( (nullopt <= o1), "" ); 35 static_assert ( (nullopt <= o2), "" ); 36 static_assert ( (o1 <= nullopt), "" ); 37 static_assert ( !(o2 <= nullopt), "" ); 38 39 static_assert (noexcept(nullopt <= o1), ""); 40 static_assert (noexcept(o1 <= nullopt), ""); 41 } 42 #endif 43 } 44