Book Image

Modern C++ Programming Cookbook - Second Edition

By : Marius Bancila
5 (1)
Book Image

Modern C++ Programming Cookbook - Second Edition

5 (1)
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)
Other Books You May Enjoy

Visiting an std::variant

std::variant is a new standard container that was added to C++17 based on the boost.variant library. A variant is a type-safe union that holds the value of one of its alternative types. Although in the previous recipe we have seen various operations with variants, the variants we used were rather simple, with POD types mostly, which is not the actual purpose for which std::variant was created. Variants are intended to be used for holding alternatives of similar non-polymorphic and non-POD types. In this recipe, we will see a more real-world example of using variants and will learn how to visit variants.

Getting ready

For this recipe, you should be familiar with the std::variant type. It is recommended that you first read the previous recipe, Using std::variant as a type-safe union.

To explain how variant visitation can be done, we will consider a variant for representing a media DVD. Let's suppose we want to model a store or library that has...