How to Use an Implementation of the PHP Observer Pattern to Get Notifications about User Activity in a Chat Room Learning from the Package Chat Observe: Observe the activity of a chat room

This package can observe the activity of a chat room.

It provides interface definitions for observers and subjects with functions that observer and subject classes.

The package also provides a user class that implements the observer classes and a chat room class that implements the subject class, which outputs a message when a user sends a message to the chat room.