C++ Reactive Programming

Subjects

A  Subject is an entity that is both an Observer and an Observable. It helps to relay notifications from one Observable (typically)  to a set of Observers. We can implement sophisticated techniques such as the caching and buffering of data using a Subject. We can also use a Subject to transform a hot Observable into a cold Observable. There are four variants of subjects implemented in RxCpp library. They are as follows:

• SimpleSubject
• BehaviorSubject
• ReplaySubject
• SynchronizeSubject

Let's write a simple program that will demonstrate the work of a Subject. The code listing will demonstrate how we can push data to a Subject and retrieve them using the Observer side of the Subject.

//------- SimpleSubject.cpp #include <rxcpp/rx.hpp> ...