Book Image

Modern C++ Programming Cookbook - Second Edition

By : Marius Bancila
Book Image

Modern C++ Programming Cookbook - Second Edition

By: Marius Bancila

Overview of this book

C++ has come a long way to be one of the most widely used general-purpose languages that is fast, efficient, and high-performance at its core. The updated second edition of Modern C++ Programming Cookbook addresses the latest features of C++20, such as modules, concepts, coroutines, and the many additions to the standard library, including ranges and text formatting. The book is organized in the form of practical recipes covering a wide range of problems faced by modern developers. The book also delves into the details of all the core concepts in modern C++ programming, such as functions and classes, iterators and algorithms, streams and the file system, threading and concurrency, smart pointers and move semantics, and many others. It goes into the performance aspects of programming in depth, teaching developers how to write fast and lean code with the help of best practices. Furthermore, the book explores useful patterns and delves into the implementation of many idioms, including pimpl, named parameter, and attorney-client, teaching techniques such as avoiding repetition with the factory pattern. There is also a chapter dedicated to unit testing, where you are introduced to three of the most widely used libraries for C++: Boost.Test, Google Test, and Catch2. By the end of the book, you will be able to effectively leverage the features and techniques of C++11/14/17/20 programming to enhance the performance, scalability, and efficiency of your applications.
Table of Contents (16 chapters)
13
Bibliography
14
Other Books You May Enjoy
15
Index

Implementing move semantics

Move semantics is a key feature that drives the performance improvements of modern C++. They enable moving, rather than copying, resources or, in general, objects that are expensive to copy. However, it requires that classes implement a move constructor and assignment operator. These are provided by the compiler in some circumstances, but in practice, it is often the case that you have to explicitly write them. In this recipe, we will see how to implement the move constructor and the move assignment operator.

Getting ready

You are expected to have basic knowledge of rvalue references and the special class functions (constructors, assignment operators, and destructor). We will demonstrate how to implement a move constructor and assignment operator using the following Buffer class:

class Buffer
{
  unsigned char* ptr;
  size_t length;
public:
  Buffer(): ptr(nullptr), length(0)
  {}
  explicit Buffer(size_t const size):
    ptr(new unsigned...