Book Image

C++ Reactive Programming

By : Praseed Pai, Peter Abraham
Book Image

C++ Reactive Programming

By: Praseed Pai, Peter Abraham

Overview of this book

Reactive programming is an effective way to build highly responsive applications with an easy-to-maintain code base. This book covers the essential functional reactive concepts that will help you build highly concurrent, event-driven, and asynchronous applications in a simpler and less error-prone way. C++ Reactive Programming begins with a discussion on how event processing was undertaken by different programming systems earlier. After a brisk introduction to modern C++ (C++17), you’ll be taken through language-level concurrency and the lock-free programming model to set the stage for our foray into the Functional Programming model. Following this, you’ll be introduced to RxCpp and its programming model. You’ll be able to gain deep insights into the RxCpp library, which facilitates reactive programming. You’ll learn how to deal with reactive programming using Qt/C++ (for the desktop) and C++ microservices for the Web. By the end of the book, you will be well versed with advanced reactive programming concepts in modern C++ (C++17).
Table of Contents (20 chapters)
Title Page
Copyright and Credits
Packt Upsell
Contributors
Preface
Index

The Active object pattern


An Active object is a class that decouples method invocations and method executions, and is well suited for fire and forget asynchronous calls. A scheduler attached to the class handles the execution requests. The pattern consists of six elements, which are as follows:

  • A proxy, which provides an interface for clients with publicly accessible methods
  • An interface that defines the method request on an Active object
  • A list of pending requests from clients
  • A Scheduler, which decides which request to execute next
  • The implementation of the Active object method
  • A callback or variable, for the client to receive the result

We will dissect an implementation of the Active object pattern. This program is written for elucidation; for production use, we need to use a bit more sophistication. Attempting a production quality implementation would make the code considerably longer. Let's take a look at the code:

#include <rxcpp/rx.hpp> 
#include <memory> 
#include <map&gt...