wpcockroach

 1 std::string &&
 2 get_string()
 3 {
 4   return "hello world";
 5 }
 6 
 7 int main()
 8 {
 9   auto s1 = get_string();
10   auto const s2 = get_string();
11   auto const & s3 = get_string();
12 
13   std::cout << s1 << std::endl;
14   std::cout << s2 << std::endl;
15   std::cout << s3 << std::endl;
16 
17   return 0;
18 }

 1 template <typename T>
 2 T &&
 3 value(optional<T> && v)
 4 {
 5 #if defined TKAT_APPLE_CLANG && TKAT_APPLE_CLANG <= 9020039
 6   // https://stackoverflow.com/questions/44217316/how-do-i-use-stdoptional-in-c
 7   return std::move(*std::move(v));
 8 #else
 9 
10 # if !defined NDEBUG
11   try
12   {
13     return std::move(v).value();
14   }
15   catch (std::bad_optional_access const & eh)
16   {
17     TKAT_LOG_TEST_ENVIRONMENT(eh.what());
18     throw;
19   }
20 # else
21   return std::move(v).value();
22 # endif
23 
24 #endif
25 }