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)
13
Bibliography
14
Other Books You May Enjoy
15
Index

Using std::conditional to choose between types

In the previous recipes, we looked at some of the features from the type support library, and type traits in particular. Related topics have been discussed in other parts of this book, such as using std::enable_if to hide function overloads, in Chapter 4, Preprocessing and Compilation, and std::decay to remove const and volatile qualifiers, when we discussed visiting variants, also in this chapter. Another type transformation feature worth discussing to a larger extent is std::conditional, which enables us to choose between two types at compile time, based on a compile-time Boolean expression. From this recipe, you will learn how it works and how to use it through several examples.

Getting ready

It is recommended that you first read the Using type traits to query properties of types recipe, earlier in this chapter.

How to do it...

The following is a list of examples that show you how to use std::conditional (and std...