issues about exercise 13.49

[LvXinTao]

Hi.In the given answer, I see that you use
String::String(String &&s) NOEXCEPT : elements(s.elements), end(s.end) { s.elements = s.end = nullptr; }
instead of
String::String(String&&s)NOEXCEPT :elements(std::move(s.elements)),end(std::move(s.end)) { ... }
in the initialized list of move constructor "String(String&&)", and so as in StrVec.
My question is that: would that do the COPY instead of MOVE?