Snobol4 语言 实战 开发文本分析工具链实战

Snobol4 语言实战：开发文本分析工具链

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。尽管它已经不像其他现代编程语言那样流行，但Snobol4 在文本处理方面有着独特的优势。本文将围绕Snobol4 语言，实战开发一个文本分析工具链，以展示其在文本处理方面的潜力。

Snobol4 简介

Snobol4 是一种基于字符串的编程语言，特别适合于文本处理任务。它具有以下特点：

- 强大的字符串处理能力
- 简洁的表达式语法
- 高效的运行速度
- 支持多种文本处理操作，如搜索、替换、排序等

文本分析工具链设计

我们的文本分析工具链将包括以下功能：

1. 文本读取与预处理
2. 文本分词
3. 词频统计
4. 文本摘要
5. 文本分类

下面，我们将使用Snobol4 语言实现这些功能。

1. 文本读取与预处理

我们需要从文件中读取文本，并进行一些预处理操作，如去除空白字符、标点符号等。

```snobol
READ "input.txt"
PUTOUT "output.txt"
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