Book Image

Mastering Object-Oriented Python - Second Edition

By : Steven F. Lott
Book Image

Mastering Object-Oriented Python - Second Edition

By: Steven F. Lott

Overview of this book

Object-oriented programming (OOP) is a relatively complex discipline to master, and it can be difficult to see how general principles apply to each language's unique features. With the help of the latest edition of Mastering Objected-Oriented Python, you'll be shown how to effectively implement OOP in Python, and even explore Python 3.x. Complete with practical examples, the book guides you through the advanced concepts of OOP in Python, and demonstrates how you can apply them to solve complex problems in OOP. You will learn how to create high-quality Python programs by exploring design alternatives and determining which design offers the best performance. Next, you'll work through special methods for handling simple object conversions and also learn about hashing and comparison of objects. As you cover later chapters, you'll discover how essential it is to locate the best algorithms and optimal data structures for developing robust solutions to programming problems with minimal computer processing. Finally, the book will assist you in leveraging various Python features by implementing object-oriented designs in your programs. By the end of this book, you will have learned a number of alternate approaches with different attributes to confidently solve programming problems in Python.
Table of Contents (25 chapters)
Free Chapter
1
Section 1: Tighter Integration Via Special Methods
11
Section 2: Object Serialization and Persistence
17
Section 3: Object-Oriented Testing and Debugging

Stateless objects without __init__()

The following is an example of a degenerate class that doesn't need an __init__() method. It's a common design pattern for Strategy objects. A Strategy object is plugged into some kind of master or owner object to implement an algorithm or decision. The Strategy object often depends on data in the master object; the Strategy object may not have any data of its own. We often design strategy classes to follow the Flyweight design pattern so we can avoid internal storage in the strategy instance. All values can be provided to a Strategy object as method argument values. In some cases, a strategy object can be stateless; in this instance, it is more a collection of method functions than anything else.

In the following examples, we'll show both stateless and stateful strategy class definitions. We'll start with the strategy for...