精通Python：提升代码效率与可读性的实战指南

需积分: 9 84 浏览量更新于2024-07-19 收藏 12.32MB PDF 举报

"Fluent Python 是一本由 Luciano Ramalho 撰写的书籍，旨在帮助程序员更好地理解和利用Python语言的高级特性和库，从而写出更简洁、高效且易读的代码。书中针对那些在其他语言背景下的程序员，指导他们如何摆脱习惯性的编程思维，更加流畅地编写Python代码。作者通过实例探讨了Python中的实用特性，如生成器在数据库处理中的应用、Python上下文中的设计模式重思、属性描述符及其在ORM（对象关系映射）中的作用、Python对象的理解：协议与接口、抽象基类和多重继承等主题。这本书对中级到高级的Python开发者来说是一份宝贵的资源，不仅可以提升他们的技能，还能让经验丰富的开发者学到新的知识。" 在这本书中，读者可以深入理解以下知识点： 1. **生成器**：生成器是Python中一种强大的迭代器实现方式，它允许你在运行时动态生成值，而不必一次性创建所有数据。在处理大量数据或数据库操作时，使用生成器可以显著提高内存效率和性能。 2. **设计模式的Python化思考**：书中的这部分内容会引导读者重新审视在不同编程语言中常见的设计模式，并讨论如何在Python中以更自然的方式实现这些模式，避免不适应Python语法的尝试。 3. **属性描述符**：这是理解Python对象模型的关键部分，属性描述符可以控制对象的属性访问，使得ORM（对象关系映射）等高级功能得以实现。通过学习这部分，读者可以了解如何自定义属性的行为，以及何时应该使用它们。 4. **Python对象的理解**：书中会讨论Python对象的协议（如可迭代性、可调用性等）和接口的区别，以及如何使用抽象基类和多重继承来构建灵活的类结构。这些概念对于编写健壮且可扩展的Python代码至关重要。 5. **抽象基类和多重继承**：Python支持多重继承，这使得代码可以复用多个类的功能。抽象基类（ABCs）提供了一种标准的方式来定义接口，即使在没有具体实现的情况下也可以。了解这些知识可以帮助开发者更好地组织和设计复杂系统。 "Fluent Python"这本书不仅涵盖了Python的核心语言特性，还深入到一些高级话题，是Python开发者进一步提升技能的理想读物。通过阅读此书，你将能够掌握编写高质量Python代码的技巧，让你的代码更加符合Pythonic的风格。

Descriptor Usage Tips 648

Descriptor docstring and Overriding Deletion 650

Chapter Summary 651

Further Reading 679

Afterword. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 683

A. Support Scripts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 687

Python Jargon. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 715

Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 725

xiv | Table of Contents

Python package index now lists more than 60,000 libraries and many of them are in‐

credibly useful.

Who This Book Is For

This book was written for practicing Python programmers who want to become pro‐

ficient in Python 3. If you know Python 2 but are willing to migrate to Python 3.4 or

later, you should be fine. At the time of this writing, the majority of professional Python

programmers are using Python 2, so I took special care to highlight Python 3 features

that may be new to that audience.

However, Fluent Python is about making the most of Python 3.4, and I do not spell out

the fixes needed to make the code work in earlier versions. Most examples should run

in Python 2.7 with little or no changes, but in some cases, backporting would require

significant rewriting.

Having said that, I believe this book may be useful even if you must stick with Python

2.7, because the core concepts are still the same. Python 3 is not a new language, and

most differences can be learned in an afternoon. What’s New in Python 3.0 is a good

starting point. Of course, there have been changes since Python 3.0 was released in 2009,

but none as important as those in 3.0.

If you are not sure whether you know enough Python to follow along, review the topics

of the official Python Tutorial. Topics covered in the tutorial will not be explained here,

except for some features that are new in Python 3.

Who This Book Is Not For

If you are just learning Python, this book is going to be hard to follow. Not only that, if

you read it too early in your Python journey, it may give you the impression that every

Python script should leverage special methods and metaprogramming tricks. Premature

abstraction is as bad as premature optimization.

How This Book Is Organized

The core audience for this book should not have trouble jumping directly to any chapter

in this book. However, each of the six parts forms a book within the book. I conceived

the chapters within each part to be read in sequence.

I tried to emphasize using what is available before discussing how to build your own.

For example, in Part II, Chapter 2 covers sequence types that are ready to use, including

some that don’t get a lot of attention, like collections.deque. Building user-defined

sequences is only addressed in Part IV, where we also see how to leverage the abstract

base classes (ABCs) from collections.abc. Creating your own ABCs is discussed even

xvi | Preface

later in Part IV, because I believe it’s important to be comfortable using an ABC before

writing your own.

This approach has a few advantages. First, knowing what is ready to use can save you

from reinventing the wheel. We use existing collection classes more often than we im‐

plement our own, and we can give more attention to the advanced usage of available

tools by deferring the discussion on how to create new ones. We are also more likely to

inherit from existing ABCs than to create a new ABC from scratch. And finally, I believe

it is easier to understand the abstractions after you’ve seen them in action.

The downside of this strategy are the forward references scattered throughout the

chapters. I hope these will be easier to tolerate now that you know why I chose this path.

Here are the main topics in each part of the book:

Part I

A single chapter about the Python data model explaining how the special methods

(e.g., __repr__) are the key to the consistent behavior of objects of all types—in a

language that is admired for its consistency. Understanding various facets of the

data model is the subject of most of the rest of the book, but Chapter 1 provides a

high-level overview.

Part II

The chapters in this part cover the use of collection types: sequences, mappings,

and sets, as well as the str versus bytes split—the cause of much celebration among

Python 3 users and much pain for Python 2 users who have not yet migrated their

code bases. The main goals are to recall what is already available and to explain

some behavior that is sometimes surprising, like the reordering of dict keys when

we are not looking, or the caveats of locale-dependent Unicode string sorting. To

achieve these goals, the coverage is sometimes high level and wide (e.g., when many

variations of sequences and mappings are presented) and sometimes deep (e.g.,

when we dive into the hash tables underneath the dict and set types).

Part III

Here we talk about functions as first-class objects in the language: what that means,

how it affects some popular design patterns, and how to implement function dec‐

orators by leveraging closures. Also covered here is the general concept of callables

in Python, function attributes, introspection, parameter annotations, and the new

nonlocal declaration in Python 3.

Part IV

Now the focus is on building classes. In Part II, the class declaration appears in

few examples; Part IV presents many classes. Like any object-oriented (OO) lan‐

guage, Python has its particular set of features that may or may not be present in

the language in which you and I learned class-based programming. The chapters

explain how references work, what mutability really means, the lifecycle of instan‐

Preface | xvii

ces, how to build your own collections and ABCs, how to cope with multiple in‐

heritance, and how to implement operator overloading—when that makes sense.

Part V

Covered in this part are the language constructs and libraries that go beyond se‐

quential control flow with conditionals, loops, and subroutines. We start with gen‐

erators, then visit context managers and coroutines, including the challenging but

powerful new yield from syntax. Part V closes with a high-level introduction to

modern concurrency in Python with collections.futures (using threads and

processes under the covers with the help of futures) and doing event-oriented I/O

with asyncio (leveraging futures on top of coroutines and yield from).

Part VI

This part starts with a review of techniques for building classes with attributes

created dynamically to handle semi-structured data such as JSON datasets. Next,

we cover the familiar properties mechanism, before diving into how object attribute

access works at a lower level in Python using descriptors. The relationship between

functions, methods, and descriptors is explained. Throughout Part VI, the step-by-

step implementation of a field validation library uncovers subtle issues that lead to

the use of the advanced tools of the final chapter: class decorators and metaclasses.

Hands-On Approach

Often we’ll use the interactive Python console to explore the language and libraries. I

feel it is important to emphasize the power of this learning tool, particularly for those

readers who’ve had more experience with static, compiled languages that don’t provide

a read-eval-print#loop (REPL).

One of the standard Python testing packages, doctest, works by simulating console

sessions and verifying that the expressions evaluate to the responses shown. I used

doctest to check most of the code in this book, including the console listings. You don’t

need to use or even know about doctest to follow along: the key feature of doctests is

that they look like transcripts of interactive Python console sessions, so you can easily

try out the demonstrations yourself.

Sometimes I will explain what we want to accomplish by showing a doctest before the

code that makes it pass. Firmly establishing what is to be done before thinking about

how to do it helps focus our coding effort. Writing tests first is the basis of test driven

development (TDD) and I’ve also found it helpful when teaching. If you are unfamiliar

with doctest, take a look at its documentation and this book’s source code repository.

You’ll find that you can verify the correctness of most of the code in the book by typing

python3 -m doctest example_script.py in the command shell of your OS.

xviii | Preface

剩余765页未读，继续阅读

哈北儿

粉丝: 7
资源: 8

精通Python：提升代码效率与可读性的实战指南

Fluent Python(最新版 原版 高清 带书签)

fluent python.zip

fluent python

fluentPython

fluent_python_exercises:Fluent Python上的IDinsight DSEM阅读小组练习

fluent python 中英合集

fluent python pdf

fluent python 2nd pdf

fluent python英文版

基于React框架的react-demo设计源码学习参考

最新资源

Fluent Python(最新版原版高清带书签)