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

Exploring abbreviated function templates

In Chapter 3, we learned about function templates as well as lambda expressions, including generic and template lambdas. A generic lambda is a lambda expression that uses auto specified for one of its parameters. The result is a function object with a templated call operator. The same is produced as a result of defining a lambda template that has the advantage, over generic lambdas, of allowing better control over the types of the parameters. In C++20, this idea of using the auto specifier for parameter types is generalized for all functions.

This introduces a simplified syntax of defining function templates, and functions that are defined in this way are called abbreviated function templates. We will see in this recipe how to use them.

How to do it…

You can define the following categories of abbreviated function templates in C++20:

  • Unconstrained abbreviated function templates that use the auto specifier to define...