Snobol4 语言 实战 Markdown 列表嵌套解析实战

Snobol4^【1】 语言实战：Markdown^【3】 列表嵌套解析实战

Markdown 是一种轻量级标记语言，常用于格式化文本。它广泛应用于博客、论坛和文档中。Markdown 支持多种列表格式，包括无序列表^【4】和有序列表^【5】。在复杂的文档中，列表可能会嵌套使用，形成多层嵌套的列表结构。本文将使用 Snobol4 语言，一种古老的编程语言，来解析 Markdown 列表，并处理嵌套列表^【6】的情况。

Snobol4 简介

Snobol4 是一种高级编程语言，由 Calvin Mooers^【7】 在 1962 年发明。它以其强大的字符串处理^【8】能力而闻名，特别适合于文本处理^【9】任务。Snobol4 的语法简洁，易于理解，但它的执行效率相对较低。

Markdown 列表格式

Markdown 列表的基本格式如下：

- 无序列表：使用 `-`、`` 或 `+` 开头，例如：

- 项目 1
- 项目 2
- 项目 3


- 有序列表：使用数字和句点开头，例如：

1. 项目 1
2. 项目 2
3. 项目 3


- 嵌套列表：使用缩进来表示列表的层级，例如：

1. 项目 1
- 子项目 1.1
- 子项目 1.2
2. 项目 2
- 子项目 2.1


snobol^【2】4 解析 Markdown 列表

以下是一个使用 Snobol4 语言编写的示例程序，用于解析 Markdown 列表：

```snobol
:parse-list<sup>【10】</sup>
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