Snobol4 语言 实战 实现文本格式化系统实战

Snobol4 语言实战：实现文本格式化系统

Snobol4 是一种古老的编程语言，最初在1962年由David J. Farber、Ralph E. Griswold 和 Ivan P. Polonsky 在贝尔实验室开发。它以其强大的字符串处理能力而闻名，特别适合于文本处理任务。本文将探讨如何使用 Snobol4 语言实现一个简单的文本格式化系统，包括文本缩进、行宽限制、标题格式化等功能。

Snobol4 简介

Snobol4 是一种高级编程语言，它结合了过程式和函数式编程的特点。它的语法简洁，易于理解，特别适合于文本处理。Snobol4 的主要特点包括：

- 强大的字符串处理能力
- 简洁的语法
- 高效的运行速度
- 支持模式匹配和正则表达式

文本格式化系统设计

功能需求

我们的文本格式化系统需要实现以下功能：

1. 自动缩进
2. 行宽限制
3. 标题格式化
4. 段落分隔

系统架构

系统将分为以下几个模块：

1. 输入处理模块：负责读取用户输入的文本。
2. 格式化模块：根据用户需求对文本进行格式化处理。
3. 输出模块：将格式化后的文本输出到屏幕或文件。

实现代码

以下是一个简单的 Snobol4 程序，实现了上述功能：

```snobol
:input
input line
:process
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