6. Text Processing Services
***************************

The modules described in this chapter provide a wide range of string
manipulation operations and other text processing services.

The "codecs" module described under Binary Data Services is also
highly relevant to text processing. In addition, see the documentation
for Python's built-in string type in Text Sequence Type --- str.

* 6.1. "string" --- 常见的字符串操作

  * 6.1.1. 字符串常量

  * 6.1.2. Custom String Formatting

  * 6.1.3. Format String Syntax

    * 6.1.3.1. Format Specification Mini-Language

    * 6.1.3.2. Format examples

  * 6.1.4. Template strings

  * 6.1.5. Helper functions

* 6.2. "re" — 正则表达式操作

  * 6.2.1. 正则表达式语法

  * 6.2.2. 模块内容

  * 6.2.3. 正则表达式对象 （正则对象）

  * 6.2.4. 匹配对象

  * 6.2.5. 正则表达式例子

    * 6.2.5.1. 检查对子

    * 6.2.5.2. 模拟 scanf()

    * 6.2.5.3. search() vs. match()

    * 6.2.5.4. 建立一个电话本

    * 6.2.5.5. 文字整理

    * 6.2.5.6. 找到所有副词

    * 6.2.5.7. 找到所有副词和位置

    * 6.2.5.8. 原始字符记法

    * 6.2.5.9. 写一个词法分析器

* 6.3. "difflib" --- Helpers for computing deltas

  * 6.3.1. SequenceMatcher Objects

  * 6.3.2. SequenceMatcher Examples

  * 6.3.3. Differ Objects

  * 6.3.4. Differ Example

  * 6.3.5. A command-line interface to difflib

* 6.4. "textwrap" --- Text wrapping and filling

* 6.5. "unicodedata" --- Unicode Database

* 6.6. "stringprep" --- Internet String Preparation

* 6.7. "readline" --- GNU readline interface

  * 6.7.1. Init file

  * 6.7.2. Line buffer

  * 6.7.3. History file

  * 6.7.4. History list

  * 6.7.5. Startup hooks

  * 6.7.6. Completion

  * 6.7.7. 示例

* 6.8. "rlcompleter" --- Completion function for GNU readline

  * 6.8.1. Completer Objects
