Book Image

Modern C++ Programming Cookbook

By : Marius Bancila
Book Image

Modern C++ Programming Cookbook

By: Marius Bancila

Overview of this book

C++ is one of the most widely used programming languages. Fast, efficient, and flexible, it is used to solve many problems. The latest versions of C++ have seen programmers change the way they code, giving up on the old-fashioned C-style programming and adopting modern C++ instead. Beginning with the modern language features, each recipe addresses a specific problem, with a discussion that explains the solution and offers insight into how it works. You will learn major concepts about the core programming language as well as common tasks faced while building a wide variety of software. You will learn about concepts such as concurrency, performance, meta-programming, lambda expressions, regular expressions, testing, and many more in the form of recipes. These recipes will ensure you can make your applications robust and fast. By the end of the book, you will understand the newer aspects of C++11/14/17 and will be able to overcome tasks that are time-consuming or would break your stride while developing.
Table of Contents (19 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Conditionally compiling classes and functions with enable_if


Template metaprogramming is a powerful feature of C++ that enables us to write generic classes and functions that work with any type. That is actually a problem sometimes because the language does not define any mechanism for specifying constraints on the types that can be substituted for the template parameters. However, we can still achieve that using metaprogramming tricks and leveraging a rule called substitution failure is not an error, known shortly as SFINAE. This recipe will focus on implementing type constraints for templates.

Getting ready

Developers have used a class template usually called enable_if for many years in conjunction with SFINAE to implement constraints on template types. The enable_if family of templates has become part of the C++11 standard and is implemented as follows:

    template<bool Test, class T = void> 
    struct enable_if 
    {}; 

    template<class T> 
    struct enable_if<true...