Using cmd for creating command-line applications

There are several ways of creating interactive applications. The Using input() and getpass() for user input recipe looked at functions such as input() and getpass.getpass(). The Using argparse to get command-line input recipe showed how to use argparse to create applications with which a user can interact from the OS command line.

We have a third way to create interactive applications using the cmd module. This module will prompt the user for input, and then invoke a specific method of the class we provide.

This is related to material in Chapter 7, More Advanced Class Design . We'll add features to a class definition to create a unique subclass.

Here's how the interaction will look, we've marked user input like this: "help":

Starting with 100

Roulette> help
Documented commands (type help <topic>):

======================================== 
bet  help 
 
Undocumented commands: 
======================...