Book Image

Modern C++ Programming Cookbook - Third Edition

By : Marius Bancila
Book Image

Modern C++ Programming Cookbook - Third Edition

By: Marius Bancila

Overview of this book

The updated third edition of Modern C++ Programming Cookbook addresses the latest features of C++23, such as the stack library, the expected and mdspan types, span buffers, formatting library improvements, and updates to the ranges library. It also gets into more C++20 topics not previously covered, such as sync output streams and source_location. The book is organized in the form of practical recipes covering a wide range of real-world problems. It gets into the details of all the core concepts of 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. You will cover the performance aspects of programming in depth, and learning to write fast and lean code with the help of best practices. You will explore useful patterns and the implementation of many idioms, including pimpl, named parameter, attorney-client, and the factory pattern. A chapter dedicated to unit testing introduces you to three of the most widely used libraries for C++: Boost.Test, Google Test, and Catch2. By the end of this modern C++ programming book, you will be able to effectively leverage the features and techniques of C++11/14/17/20/23 programming to enhance the performance, scalability, and efficiency of your applications.
Table of Contents (15 chapters)
13
Other Books You May Enjoy
14
Index

Consistent comparison with the operator <=>

The C++ language defines six relational operators that perform comparison: ==, !=, <, <=, >, and >=. Although != can be implemented in terms of ==, and <=, >=, and > in terms of <, you still have to implement both == and != if you want your user-defined type to support equality comparison, and <, <=, >, and >= if you want it to support ordering.

That means 6 functions if you want objects of your type—let’s call it T—to be comparable, 12 if you want them to be comparable with another type, U, 18 if you also want values of a U type to be comparable with your T type, and so on. The new C++20 standard reduces this number to either one or two, or multiple of these (depending on the comparison with other types) by introducing a new comparison operator, called the three-way comparison, which is designated with the symbol <=>, for which reason it is popularly known as the spaceship...