Hands-On Reactive Programming with Python

A reactive echo application

After this short introduction to ReactiveX and RxPY, the time has come to see some concrete code and write a first example. This first RxPY application is a command line interface (CLI) program that echoes the parameters that are provided as input. Save the following code in a file called echo1.py, or use the echo1.py script from the Git repository of this book, as shown in the following code:

import sysfrom rx import Observableargv = Observable.from_(sys.argv[1:])argv.subscribe(    on_next=lambda i: print("on_next: {}".format(i)),    on_error=lambda e: print("on_error: {}".format(e)),    on_completed=lambda: print("on_completed"))

Ensure that you are running in virutalenv, as shown in the following code:

$ source venv-rx/bin/activate ...