This has instance contains a certain number of instructions that will happened before, with other fields in Computer Science. They receive control There are still people, for instance, that call Artificial from an inference processor, a procedural program that Intelligence to any program that is written in Prolog or decides in every moment the order in which the sentences Lisp. In the same way, there are those who maintain that of the program should receive control should be fired.
As in the AI example, this is not always the case. In both the procedural and the non-procedural cases, the basic unit of execution is the program. The data only Another source of confusion comes from the fact that provide values that will be used to perform computations Object-Oriented Programming has been frequently used to or to decide the order of execution.
A given application is build complicated user interfaces, with window systems, a hierarchical set of programs modules each of which is icons and so forth, and this has produced the unexpected capable of invoking other programs in the hierarchy.
The result that many people believe that any program including data may be global accessible from every program in the these interfaces is OOP. Again, this is obviously wrong.
Here it is the dura that are organized in a structure and is a part of an organization. It embodies basic control hierarchy. One piece of data may be linked three different concepts: to another through a relation of descendancy, and this fact l A set of relations to other objects usually represented gives rise to a network usually a tree similar to the by pointers.
There are also programs in OOP, but they are appendages to the l A set of properties which have values. It is possible to build global code. What other programming systems call functions, Permission to copy without fee all or part of this material is granted provided that the copies an not made or dlstributsd for direct commercial advantage, the ACM programs or procedures, Object-Oriented Programming copyright notice and the title of the publication and its date appear, and notice calls methods.
There is no essential difference between is given that copying Is by permission of the Association for Computing programs in any language and methods, except for the fact Machinery. By the end of the book, you will have thoroughly learned object-oriented principles using Python syntax and be able to create robust and reliable programs confidently.
What you will learn Implement objects in Python by creating classes and defining methods Grasp common concurrency techniques and pitfalls in Python 3 Extend class functionality using inheritance Understand when to use object-oriented features, and more importantly when not to use them Discover what design patterns are and why they are different in Python Uncover the simplicity of unit testing and why it's so important in Python Explore concurrent object-oriented programming Who this book is for If you're new to object-oriented programming techniques, or if you have basic Python skills and wish to learn in depth how and when to correctly apply OOP in Python, this is the book for you.
If you are an object-oriented programmer for other languages or seeking a leg up in the new world of Python 3. Previous experience with Python 3 is not necessary. It runs on all major platforms in a huge array of use cases. Coding in Python minimizes development time and increases productivity in comparison to other languages. Clean, maintainable code is easy to both read and write using Python's clear, concise syntax.
Object-oriented programming is a popular design paradigm in which data and behaviors are encapsulated in such a way that they can be manipulated together. Many modern programming languages utilize the powerful concepts behind object-oriented programming and Python is no exception. Starting with a detailed analysis of object-oriented analysis and design, you will use the Python programming language to clearly grasp key concepts from the object-oriented paradigm. This book fully explains classes, data encapsulation, inheritance, polymorphism, abstraction, and exceptions with an emphasis on when you can use each principle to develop well-designed software.
You'll get an in-depth analysis of many common object-oriented design patterns that are more suitable to Python's unique style. This book will not just teach Python syntax, but will also build your confidence in how to program. You will also learn how to create maintainable applications by studying higher level design patterns.
Following this, 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 in the book. After you discover the joy of unit testing and just how easy it can be, you'll study higher level libraries such as database connectors and GUI toolkits and learn how they uniquely apply object-oriented principles.
You'll learn how these principles will allow you to make greater use of key members of the Python eco-system such as Django and Kivy. This new edition includes all the topics that made Python 3 Object-oriented Programming an instant Packt classic. It's also packed with updated content to reflect recent changes in the core Python library and covers modern third-party packages that were not available on the Python 3 platform when the book was first published.
Style and approachThroughout the book you will learn key object-oriented programming techniques demonstrated by comprehensive case studies in the context of a larger project. Downloading the example code for this book You can d What You Will Learn Implement objects in Python by creating classes and defining methods Separate related objects into a taxonomy of classes and describe the properties and behaviors of those objects via the class interface Extend class functionality using inheritance Understand when to use object-oriented features, and more importantly when not to use them Discover what design patterns are and why they are different in Python Uncover the simplicity of unit testing and why it's so important in Python Grasp common concurrency techniques and pitfalls in Python 3 Exploit object-oriented programming in key Python technologies such as Kivy and Django.
Object-oriented programming concurrently with asyncio In Detail Python 3 is more versatile and easier to use than ever. Style and approach Throughout the book you will learn key object-oriented programming techniques demonstrated by comprehensive case studies in the context of a larger project. Lott Publisher: ISBN: Category: Computers Page: View: Gain comprehensive insights into programming practices, and code portability and reuse to build flexible and maintainable apps using object-oriented principles Key Features Extend core OOP techniques to increase integration of classes created with Python Explore various Python libraries for handling persistence and object serialization Learn alternative approaches for solving programming problems, with different attributes to address your problem domain Book Description 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.
Typically you refer to this as "overriding the base class implementation". The virtual keyword specifies that derived classes may override the behavior.
You can also declare abstract methods where derived classes must override the behavior. The base class does not provide an implementation for an abstract method.
Next, you need to define the implementation for two of the new classes you've created. Start with the InterestEarningAccount :. Add the following code to the LineOfCreditAccount. The code negates the balance to compute a positive interest charge that is withdrawn from the account:. The GiftCardAccount class needs two changes to implement its month-end functionality.
First, modify the constructor to include an optional amount to add each month:. The constructor provides a default value for the monthlyDeposit value so callers can omit a 0 for no monthly deposit. Next, override the PerformMonthEndTransactions method to add the monthly deposit, if it was set to a non-zero value in the constructor:. The override applies the monthly deposit set in the constructor. Verify the results. Now, add a similar set of test code for the LineOfCreditAccount :.
When you add the preceding code and run the program, you'll see something like the following error:. The actual output includes the full path to the folder with the project. The folder names were omitted for brevity. Also, depending on your code format, the line numbers may be slightly different.
This code fails because the BankAccount assumes that the initial balance must be greater than 0. Another assumption baked into the BankAccount class is that the balance can't go negative.
Instead, any withdrawal that overdraws the account is rejected. Both of those assumptions need to change. The line of credit account starts at 0, and generally will have a negative balance.
Also, if a customer borrows too much money, they incur a fee. The transaction is accepted, it just costs more. The first rule can be implemented by adding an optional argument to the BankAccount constructor that specifies the minimum balance. The default is 0. The second rule requires a mechanism that enables derived classes to modify the default algorithm.
In a sense, the base class "asks" the derived type what should happen when there's an overdraft. The default behavior is to reject the transaction by throwing an exception. Let's start by adding a second constructor that includes an optional minimumBalance parameter. This new constructor does all the actions done by the existing constructor.
Also, it sets the minimum balance property. You could copy the body of the existing constructor. Instead, you can use constructor chaining to have one constructor call another. The following code shows the two constructors and the new additional field:. The preceding code shows two new techniques.
First, the minimumBalance field is marked as readonly. That means the value cannot be changed after the object is constructed.
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