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 // class bad_optional_access;
13 // bad_optional_access& operator=(const bad_optional_access&);
14 
15 #include <experimental/optional>
16 #include <string>
17 #include <cstring>
18 #include <type_traits>
19 #include <cassert>
20 
21 int main()
22 {
23 #if _LIBCPP_STD_VER > 11
24     using std::experimental::bad_optional_access;
25 
26     static_assert(std::is_nothrow_copy_assignable<bad_optional_access>::value, "");
27     const std::string s1("one message");
28     const std::string s2("another message");
29     bad_optional_access e1(s1);
30     bad_optional_access e2(s2);
31     assert(std::strcmp(e1.what(), e2.what()) != 0);
32     e1 = e2;
33     assert(std::strcmp(e1.what(), e2.what()) == 0);
34 #endif  // _LIBCPP_STD_VER > 11
35 }
36