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README.md

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+# lezer-markdown-obsidian
+
+This package is a set of extensions for [@lezer/markdown](https://github.com/lezer-parser/markdown) to add support for the Obsidian's added markdown syntax.
+
+**Warning: This is not the parser that Obsidian itself uses. All parsing is a best attempt to match the way Obsidian parses markdown, and will not guarantee a 1-for-1 replication.**
+
+If you recognize a difference in parsing, please open an issue.
+
+## `parser`
+
+The simplest was to use the library if you want full obsidian parsing is to import the parser:
+
+```typescript
+import { parser } from "lezer-markdown-obsidian";
+
+const tree = parser.parse("# Some Markdown");
+```
+
+This parser includes all the extensions below, as well as the `Strikethrough` and `Table` extensions from `@lezer/markdown`.
+
+## Extensions
+
+You can configure your own parser with specific extensions:
+
+```typescript
+import { parser as mdParser } from "@lezer/markdown";
+import { Comment, InternalLink } from "lezer-markdown-obsidian";
+
+const parser = mdParser.configure([Comment, InternalLink]);
+```
+
+### `ObsidianMDExtensions`
+
+An array of all the extensions for Obsidian's markdown syntax.
+
+### `Comment`
+
+This adds support for parsing comments in the form of: `%%comment%%`.
+
+Comments that begin at the start of a line can span multiple lines, and will go to the end of the document unless terminated.
+
+Comments that are inline must be completed on the same line.
+
+### `Footnote`
+
+This adds support for detecting footnotes and footnote references.
+
+Footnotes are in the form of:
+`This has a footnote.[^1]`
+
+References are in the form of:
+`[^1]: Here is some additional info.`
+
+References can span multiple lines as long as they are not interrupted by another block.
+
+### `Hashtag`
+
+This adds support for hashtags. Hashtags are pretty flexible in what can be tagged, only forbidding certain special characters.
+
+`#this-is-a-tag`
+
+`#nested/tag`
+
+### `InternalLink`
+
+This adds support for internal links and embeds.
+
+Internal links are structured like:
+`[[File#heading|display]]`
+
+Internal embeds are structured like:
+`![[File#heading]]`
+
+The `#heading` and `|display` parts are optional. Heading can be a `#^blockid` instead, and multiple headings can be chained together.
+
+### `TaskList`
+
+This adds support for Obsidian's task lists, which allow support for arbitrary characters for tasks. This makes it different from GFM task lists.
+
+Open tasks are in the form of:
+`- [ ] This is an uncompleted task`
+
+Completed tasks are in the form of:
+`- [x] This is a completed task`
+
+Special tasks can replace `x` with any character in the completed form.
+
+### `Tex`
+
+This adds support for LaTex style formulas, both inline and block level. In Obsidian, these are rendered with MathJax.
+
+Inline is in the form of:
+`Here is some math: $1 + 2 = 3$`
+
+Block level is in the form of:
+
+```
+$$
+\vec v = \vec a t
+$$
+```
+
+**Warning: Obsidian can also parse blocks as inline elements, which is currently not supported.**
+
+### `YAMLFrontmatter`
+
+This adds support for a frontmatter block of YAML. The frontmatter must be the first block in the document, otherwise it is treated as markdown. The YAML must be surrounded by lines with `---`.
+
+For example:
+
+```
+---
+author: Eric
+---
+```
+
+**If you are parsing subselections of a document, you will want to configure a parser that does not include `YAMLFrontmatter`, since it will be unable to distinguise horizontal rules from frontmatter.**