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mdast utility that turns markdown into a syntax tree.

• What is this?
• When should I use this?
• Install
• Use
• API
  • fromMarkdown(value[, encoding][, options])
  • CompileContext
  • CompileData
  • Encoding
  • Extension
  • Handle
  • OnEnterError
  • OnExitError
  • Options
  • Token
  • Transform
  • Value
• List of extensions
• Syntax
• Syntax tree
• Types
• Compatibility
• Security
• Related
• Contribute
• License

This package is a utility that takes markdown input and turns it into anmdast syntax tree.

This utility usesmicromark,which turns markdown into tokens,and then turns those tokens into nodes.This package is used insideremark-parse,which focusses onmaking it easier to transform content by abstracting these internals away.

If you want to handle syntax trees manually, use this.When youjust want to turn markdown into HTML,usemicromark instead.For an easier time processing content,use theremark ecosystem instead.

You can combine this package with other packages to add syntax extensions tomarkdown.Notable examples that deeply integrate with this package aremdast-util-mdx,mdast-util-gfm,mdast-util-frontmatter,mdast-util-math, andmdast-util-directive.

This package isESM only.In Node.js (version 16+), install withnpm:

npm install mdast-util-from-markdown

In Deno withesm.sh:

import{fromMarkdown}from'https://esm.sh/mdast-util-from-markdown@2'

In browsers withesm.sh:

<scripttype="module">import{fromMarkdown}from'https://esm.sh/mdast-util-from-markdown@2?bundle'</script>

Say we have the following markdown fileexample.md:

##Hello,*World*!

…and our moduleexample.js looks as follows:

importfsfrom'node:fs/promises'import{fromMarkdown}from'mdast-util-from-markdown'constdoc=awaitfs.readFile('example.md')consttree=fromMarkdown(doc)console.log(tree)

…now runningnode example.js yields (positional info removed for brevity):

{type:'root',children:[{type:'heading',depth:2,children:[{type:'text',value:'Hello, '},{type:'emphasis',children:[{type:'text',value:'World'}]},{type:'text',value:'!'}]}]}

This package exports the identifierfromMarkdown.There is no default export.

The export map supports thedevelopment condition.Runnode --conditions development example.js to get instrumented dev code.Without this condition, production code is loaded.

Turn markdown into a syntax tree.

• (value: Value, encoding: Encoding, options?: Options) => Root
• (value: Value, options?: Options) => Root

• value (Value)— markdown to parse
• encoding (Encoding, default:'utf8')—character encoding for whenvalue isUint8Array
• options (Options, optional)— configuration

mdast tree (Root).

mdast compiler context (TypeScript type).

• stack (Array<Node>)— stack of nodes
• tokenStack (Array<[Token, OnEnterError | undefined]>)— stack of tokens
• data (CompileData)— info passed around; key/value store
• buffer (() => undefined)— capture some of the output data
• resume (() => string)— stop capturing and access the output data
• enter ((node: Node, token: Token, onError?: OnEnterError) => undefined)— enter a node
• exit ((token: Token, onError?: OnExitError) => undefined)— exit a node
• sliceSerialize ((token: Token, expandTabs?: boolean) => string)— get the string value of a token
• config (Required<Extension>)— configuration

Interface of tracked data (TypeScript type).

interfaceCompileData{/* see code */}

When working on extensions that use more data, extend the correspondinginterface to register their types:

declare module'mdast-util-from-markdown'{interfaceCompileData{// Register a new field.mathFlowInside?:boolean|undefined}}

Encodings supported by theUint8Array class(TypeScript type).

Seemicromark for more info.

typeEncoding='utf8'|/* … */

Change how markdown tokens from micromark are turned into mdast (TypeScripttype).

• canContainEols (Array<string>, optional)— token types where line endings are used
• enter (Record<string, Handle>, optional)— opening handles
• exit (Record<string, Handle>, optional)— closing handles
• transforms (Array<Transform>, optional)— tree transforms

Handle a token (TypeScript type).

• this (CompileContext)— context
• token (Token)— current token

Nothing (undefined).

Handle the case where theright token is open, but it is closed (by theleft token) or because we reached the end of the document (TypeScript type).

• this (CompileContext)— context
• left (Token orundefined)— left token
• right (Token)— right token

Nothing (undefined).

Handle the case where theright token is open but it is closed byexiting theleft token (TypeScript type).

• this (CompileContext)— context
• left (Token)— left token
• right (Token)— right token

Nothing (undefined).

Configuration (TypeScript type).

• extensions(Array<MicromarkExtension>, optional)— micromark extensions to change how markdown is parsed
• mdastExtensions(Array<Extension | Array<Extension>>,optional)— extensions for this utility to change how tokens are turned into a tree

Token from micromark (TypeScript type).

typeToken={/* … */}

Extra transform, to change the AST afterwards (TypeScript type).

• tree (Root)— tree to transform

New tree (Root) or nothing(in which case the current tree is used).

Contents of the file (TypeScript type).

Seemicromark for more info.

typeValue=Uint8Array|string

• syntax-tree/mdast-util-directive— directives
• syntax-tree/mdast-util-frontmatter— frontmatter (YAML, TOML, more)
• syntax-tree/mdast-util-gfm— GFM
• syntax-tree/mdast-util-gfm-autolink-literal— GFM autolink literals
• syntax-tree/mdast-util-gfm-footnote— GFM footnotes
• syntax-tree/mdast-util-gfm-strikethrough— GFM strikethrough
• syntax-tree/mdast-util-gfm-table— GFM tables
• syntax-tree/mdast-util-gfm-task-list-item— GFM task list items
• syntax-tree/mdast-util-math— math
• syntax-tree/mdast-util-mdx— MDX
• syntax-tree/mdast-util-mdx-expression— MDX expressions
• syntax-tree/mdast-util-mdx-jsx— MDX JSX
• syntax-tree/mdast-util-mdxjs-esm— MDX ESM

Markdown is parsed according to CommonMark.Extensions can add support for other syntax.If you’re interested in extending markdown,more information is available in micromark’sreadme.

The syntax tree ismdast.

This package is fully typed withTypeScript.It exports the additional typesCompileContext,CompileData,Encoding,Extension,Handle,OnEnterError,OnExitError,Options,Token,Transform, andValue.

Projects maintained by the unified collective are compatible with maintainedversions of Node.js.

When we cut a new major release, we drop support for unmaintained versions ofNode.This means we try to keep the current release line,mdast-util-from-markdown@^2, compatible with Node.js 16.

As markdown is sometimes used for HTML, and improper use of HTML can open you upto across-site scripting (XSS) attack, use ofmdast-util-from-markdowncan also be unsafe.When going to HTML, use this utility in combination withhast-util-sanitize to make the tree safe.

• syntax-tree/mdast-util-to-markdown— serialize mdast as markdown
• micromark/micromark— parse markdown
• remarkjs/remark— process markdown

Seecontributing.mdinsyntax-tree/.githubfor ways to get started.Seesupport.md for ways to get help.

This project has acode of conduct.By interacting with this repository, organization, or community you agree toabide by its terms.

MIT ©Titus Wormer