Snobol4【1】 语言文本清洗【2】最佳实践
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 设计。尽管它已经不再广泛使用，但在某些领域，如文本处理和数据处理，Snobol4 仍然有其独特的优势。本文将围绕 Snobol4 语言，探讨文本清洗的最佳实践，并分步骤展示如何处理这一主题。
文本清洗概述
文本清洗是指对原始文本数据进行预处理，以去除噪声、纠正错误、提取有用信息等。在 Snobol4 中，文本清洗通常涉及以下步骤：
1. 去除空白字符【3】
2. 去除特殊字符【4】
3. 转换大小写
4. 去除重复字符【5】
5. 提取关键词
6. 格式化输出【6】
步骤一：去除空白字符
在 Snobol4 中，可以使用 `+` 运算符去除空白字符。以下是一个简单的示例：
snobol
input: " Hello, World! "
output: "Hello,World!"
```snobol
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Comments NOTHING