Snobol4【1】 语言实战：实现文本索引系统【2】工具
Snobol4 是一种古老的编程语言，由 Stephen C. Johnson 在1962年设计。它以其简洁的语法和强大的字符串处理【3】能力而闻名。尽管 Snobol4 在现代编程语言中并不常见，但它在文本处理领域仍然有其独特的应用价值。本文将探讨如何使用 Snobol4 语言实现一个简单的文本索引系统工具。
Snobol4 简介
Snobol4 是一种高级编程语言，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
- 简洁的语法
- 高效的运行速度
- 支持模式匹配【4】和正则表达式【5】
文本索引系统工具需求分析
在实现文本索引系统工具之前，我们需要明确以下需求：
1. 索引生成【6】：能够从给定的文本文件中提取关键词，并生成索引。
2. 索引查询【7】：能够根据关键词查询索引，并返回相关文本的引用。
3. 索引存储【8】：能够将生成的索引存储在文件中，以便后续查询。
Snobol4 实现文本索引系统工具
1. 索引生成
以下是一个简单的 Snobol4 程序，用于从文本文件中提取关键词并生成索引：
```snobol
:INDEX
'INDEX' !> "INDEX FILE: "
!> "KEYWORD: "
!> "REFERENCE: "
!> "-----------------------"
!> "END"
!> "-----------------------"
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