Exploring C++20: The Programmer's Introduction to C++

© Ray Lischner 2020

R. LischnerExploring C++20https://doi.org/10.1007/978-1-4842-5961-0_64

64. Moving Data with Rvalue References

Ray Lischner¹ 

(1)

Ellicott City, MD, USA

 

In Exploration 40, I introduced std::move() without explaining what it really does or how it works. Somehow it moves data, such as a string, from one variable to another, instead of copying the string contents, but you must be wondering how it works its wonders. The function itself is surprisingly simple. The concepts that underlie that simple implementation are more complicated, which is why I have waited until now to introduce the complexities and subtleties involved.

Copying vs. Moving

As you know, the std::vector type stores an array of values. As you add more values to the vector, ...