Book Image

C++20 STL Cookbook

By : Bill Weinman
Book Image

C++20 STL Cookbook

By: Bill Weinman

Overview of this book

Fast, efficient, and flexible, the C++ programming language has come a long way and is used in every area of the industry to solve many problems. The latest version C++20 will see programmers change the way they code as it brings a whole array of features enabling the quick deployment of applications. This book will get you up and running with using the STL in the best way possible. Beginning with new language features in C++20, this book will help you understand the language's mechanics and library features and offer insights into how they work. Unlike other books, the C++20 STL Cookbook takes an implementation-specific, problem-solution approach that will help you overcome hurdles quickly. You'll learn core STL concepts, such as containers, algorithms, utility classes, lambda expressions, iterators, and more, while working on real-world recipes. This book is a reference guide for using the C++ STL with its latest capabilities and exploring the cutting-edge features in functional programming and lambda expressions. By the end of the book C++20 book, you'll be able to leverage the latest C++ features and save time and effort while solving tasks elegantly using the STL.
Table of Contents (13 chapters)

Use the "spaceship" operator <=> for three-way comparisons

The three-way comparison operator (<=>), commonly called the spaceship operator because it looks like a flying saucer in profile, is new in C++20. You may wonder, what's wrong with the existing six comparison operators? Nothing at all, and you will continue using them. The purpose of the spaceship is to provide a unified comparison operator for objects.

The common two-way comparison operators return one of two states, true or false, according to the result of the comparison. For example:

const int a = 7;
const int b = 42;
static_assert(a < b);

The a < b expression uses the less-than comparison operator (<) to test if a is less than b. The comparison operator returns true if the condition is satisfied, or false if not. In this case it returns true because 7 is less than 42.

The three-way comparison works differently. It returns one of three states. The spaceship operator will return...