Class NotCopyable

01.24-optional0/main.cpp:40–43

#A A struct with delete copy operations

// #A A struct with delete copy operations
struct NotCopyable {
  NotCopyable(const NotCopyable&) = delete;
  NotCopyable& operator=(const NotCopyable&) = delete;
};

optional<NotCopyable> a{};
optional<NotCopyable> b = a;  // #B This should fail