> You cannot assume anything about the state of a moved-from object. This is the right default assuption, but classes are allowed to have (and document) more s

> You cannot assume anything about the state of a moved-from object. This is the right default assuption, but classes are allowed to have (and document) more specific behaviour. For example, it is guaranteed that std::unique_ptr and std::shared_ptr are empty (nullptr) after they have been moved from, and std::vector is guaranteed to be empty after it is moved from so long as the destination allocator is the same. > AFAIK, the only valid operations are destruction and assigning something else to it. Even for classes whose move constructors have no guarantees, there are often other methods that don't have any preconditions, such as calling clear() or resize(0). In fact is it allowed to call other operations and they should behave consistently, it's just not guaranteed what exact value the object should have (e.g. if size() > 0 then .at(0) should not throw and a second call to it should return the same value as the first call to it).