Snobol4 语言 代码复用 封装公共子例程的原则

Snobol4阿木 发布于 19 天前 5 次阅读

阿木博主一句话概括：Snobol4【1】 语言中的代码复用【2】：封装公共子例程【3】的原则与实践

阿木博主为你简单介绍：
Snobol4 是一种古老的编程语言，以其简洁和强大的文本处理能力而闻名。在 Snobol4 编程中，代码复用是一个重要的概念，它有助于提高代码的可维护性和可读性。本文将探讨 Snobol4 语言中封装公共子例程的原则，并通过实际代码示例展示如何实现代码复用。

一、
代码复用是软件工程中的一个核心概念，它允许开发者将已有的代码块重用于不同的程序中，从而减少重复工作，提高开发效率。在 Snobol4 语言中，封装公共子例程是实现代码复用的有效途径。本文将深入探讨 Snobol4 中封装公共子例程的原则，并提供一些实践案例。

二、Snobol4 语言简介
Snobol4 是一种高级编程语言，最初设计用于文本处理。它具有以下特点：
- 强大的字符串处理能力
- 简洁的语法
- 支持模式匹配【4】和字符串替换【5】

三、封装公共子例程的原则
1. 单一职责原则【6】
每个子例程应该只负责一个功能，这样可以提高代码的可读性和可维护性。

2. 开放封闭原则【7】
子例程应该对扩展开放，对修改封闭。这意味着子例程应该能够适应新的需求，而不需要修改现有的代码。

3. 依赖倒置原则【8】
高层模块不应该依赖于低层模块，两者都应该依赖于抽象。在 Snobol4 中，这意味着子例程应该接受参数，而不是直接操作数据。

4. 接口隔离原则【9】
客户端不应该依赖于它不需要的接口。这意味着子例程应该提供清晰、简洁的接口。

四、实践案例
以下是一个 Snobol4 语言的示例，展示了如何封装一个用于查找字符串中所有单词的公共子例程。

```snobol
:findword
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
' ' get =w
|w| =w
'