//===----------------------------------------------------------------------===// // // The LLVM Compiler Infrastructure // // This file is dual licensed under the MIT and the University of Illinois Open // Source Licenses. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // <optional> // class bad_optional_access; // bad_optional_access& operator=(const bad_optional_access&); #include <experimental/optional> #include <string> #include <cstring> #include <type_traits> #include <cassert> int main() { #if _LIBCPP_STD_VER > 11 using std::experimental::bad_optional_access; static_assert(std::is_nothrow_copy_assignable<bad_optional_access>::value, ""); const std::string s1("one message"); const std::string s2("another message"); bad_optional_access e1(s1); bad_optional_access e2(s2); assert(std::strcmp(e1.what(), e2.what()) != 0); e1 = e2; assert(std::strcmp(e1.what(), e2.what()) == 0); #endif // _LIBCPP_STD_VER > 11 }