Ubuntu Unleashed 2013 Edition: Covering 12.10 and 13.04, Eighth Edition

Constructors and Destructors

To help you automate the creation and deletion of objects, you can easily override two default methods: __init__ and __del__. These are the methods called by Python when a class is being instantiated and freed, known as the constructor and destructor, respectively.

Having a custom constructor is great for when you need to accept a set of parameters for each object being created. For example, you might want each dog to have its own name on creation, and you could implement that with this code:

class Dog(object):    def __init__(self, name):        self.name = namefluffy = Dog("Fluffy")print fluffy.name

If you do not provide a name parameter when creating the Dog object, Python reports an error and stops. You can, of ...