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

Event-based Stream handling – some examples


Before we conclude this chapter, let's discuss a few examples, to work with an event-based system using the RxCpp library. In this section, we'll discuss two examples to understand how effective the RxCpp library can be in meeting real-world scenarios. We will discuss an example that demonstrates the aggregation of data in a Stream and application event handling, using the RxCpp library.

Aggregation based on Stream data

In this section, the Stream item is a user-defined type to represent an employee, and the code is intended to group the input Stream based on the roles and salaries of employees:

#include "rxcpp/rx.hpp" 
 
namespace Rx { 
    using namespace rxcpp; 
    using namespace rxcpp::sources; 
    using namespace rxcpp::subjects; 
    using namespace rxcpp::util; 
} 
 
using namespace std; 
 
struct Employee { 
    string name; 
    string role; 
    int salary; 
}; 

The libraries and namespaces required in the code are included, and the data...