C++ Primer, Fifth Edition

Move Constructors and std::move

We can avoid copying the strings by using two facilities introduced by the new library. First, several of the library classes, including string, define so-called “move constructors.” The details of how the string move constructor works—like any other detail about the implementation—are not disclosed. However, we do know that move constructors typically operate by “moving” resources from the given object to the object being constructed. We also know that the library guarantees that the “moved-from” string remains in a valid, destructible state. For string, we can imagine that each string has a pointer to an array ...