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

Context manager as a factory

We can create a context manager class, which is a factory for an application object. This gives us a pleasant separation of design considerations without cluttering up an application class with context management features.

Let's say we want a deterministic Deck for dealing in Blackjack. This isn't as useful as it might sound. For unit testing, we'll need a complete mock deck with specific sequences of cards. This has the advantage that the context manager works with the classes we already saw.

We'll extend the simple context manager shown earlier to create a Deck that can be used within the with statement context.

The following is a class that is a factory for Deck and also tweaks the random module:

class Deterministic_Deck:

def __init__(self, *args, **kw) -> None:
self.args = args
self.kw = kw

def __enter__...