Book Image

Python 3 Object Oriented Programming

By : Dusty Phillips
Book Image

Python 3 Object Oriented Programming

By: Dusty Phillips

Overview of this book

Object Oriented Programming is a very important aspect of modern programming languages. The basic principles of Object Oriented Programming are relatively easy to learn. Putting them together into working designs can be challenging.This book makes programming more of a pleasure than a chore using powerful Python 3 object-oriented features of Python 3. It clearly demonstrates the core OOP principles and how to correctly implement OOP in Python. Object Oriented Programming ranks high in importance among the many models Python supports. Yet, many programmers never bother learning the powerful features that make this language object oriented.The book teaches when and how OOP should be correctly applied. It emphasizes not only the simple syntax of OOP in Python, but also how to combine these objects into well-designed software.This book will introduce you to the terminology of the object-oriented paradigm, focusing on object-oriented design with step-by-step examples. It will take you from simple inheritance, one of the most useful tools in the object-oriented programmer's toolbox, all the way through to cooperative inheritance, one of the most complicated. You will be able to raise, handle, define, and manipulate exceptions.You will be able to integrate the object-oriented and the not-so-object-oriented aspects of Python. You will also be able to create maintainable applications by studying higher level design patterns. You'll learn the complexities of string and file manipulation, and how Python distinguishes between binary and textual data. Not one, but two very powerful automated testing systems will be introduced to you. You'll understand the joy of unit testing and just how easy they are to create. You'll even study higher level libraries such as database connectors and GUI toolkits and how they apply object-oriented principles.
Table of Contents (18 chapters)
Python 3 Object Oriented Programming
Credits
About the Author
About the Reviewers
Preface
Index

Using properties to add behavior to class data


Throughout this book, we've been focusing on the separation of behavior and data. This is very important in object-oriented programming, but we're about to see that, in Python, the distinction can be eerily blurry. Python is very good at blurring distinctions; it doesn't exactly help us to "think outside the box". Rather, it teaches us that the box is in our own head; "there is no box".

Before we get into the details, let's discuss some bad object-oriented theory. Many object-oriented languages (Java is the most guilty) teach us to never access attributes directly. They teach us to write attribute access like this:

class Color:
    def __init__(self, rgb_value, name):
        self._rgb_value = rgb_value
        self._name = name

    def set_name(self, name):
        self._name = name
    
    def get_name(self):
        return self._name

The variables are prefixed with an underscore to suggest that they are private (in other languages it would...