Implementation
There are many ways to implement Chain of Responsibility in Python, but my favorite implementation is the one by Vespe Savikko [j.mp/savviko]. Vespe's implementation uses dynamic dispatching in a Pythonic style to handle requests [j.mp/ddispatch].
Let's implement a simple event-based system using Vespe's implementation as a guide. The following is the UML class diagram of the system:
The Event
class describes an event. We'll keep it simple, so in our case an event has only name
:
class Event: def __init__(self, name): self.name = name def __str__(self): return self.name
The Widget
class is the core class of the application. The parent ...
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