Mastering Python Regular Expressions电子书

Mastering Python Regular Expressions

Table of Contents

Mastering Python Regular Expressions

Credits

About the Authors

About the Reviewers

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Preface

What this book covers

What you need for this book

Who this book is for

Conventions

Reader feedback

Customer support

Downloading the example code

Errata

Piracy

Questions

1. Introducing Regular Expressions

History, relevance, and purpose

The regular expression syntax

Literals

Character classes

Predefined character classes

Alternation

Quantifiers

Greedy and reluctant quantifiers

Boundary Matchers

Summary

2. Regular Expressions with Python

A brief introduction

Backslash in string literals

String Python 2.x

Building blocks for Python regex

RegexObject

Searching

match(string[, pos[, endpos]])

search(string[, pos[, endpos]])

findall(string[, pos[, endpos]])

finditer(string[, pos[, endpos]])

Modifying a string

split(string, maxsplit=0)

sub(repl, string, count=0)

subn(repl, string, count=0)

MatchObject

group([group1, …])

groups([default])

groupdict([default])

start([group])

end([group])

span([group])

expand(template)

Module operations

escape()

purge()

Compilation flags

re.IGNORECASE or re.I

re.MULTILINE or re.M

re.DOTALL or re.S

re.LOCALE or re.L

re.UNICODE or re.U

re.VERBOSE or re.X

re.DEBUG

Python and regex special considerations

Differences between Python and other flavors

Unicode

What's new in Python 3

Summary

3. Grouping

Introduction

Backreferences

Named groups

Non-capturing groups

Atomic groups

Special cases with groups

Flags per group

yes-pattern|no-pattern

Overlapping groups

Summary

4. Look Around

Look ahead

Negative look ahead

Look around and substitutions

Look behind

Negative look behind

Look around and groups

Summary

5. Performance of Regular Expressions

Benchmarking regular expressions with Python

The RegexBuddy tool

Understanding the Python regex engine

Backtracking

Optimization recommendations

Reuse compiled patterns

Extract common parts in alternation

Shortcut to alternation

Use non-capturing groups when appropriate

Be specific

Don't be greedy

Summary

Index