README

remark-stringify

remark plugin to add support for serializing markdown.

What is this?
When should I use this?
Install
Use
API
- unified().use(remarkStringify[, options])
Syntax
Syntax tree
Types
Security
Contribute
Sponsor
License

What is this?

This package is a unified (remark) plugin that defines how to take a syntax tree as input and turn it into serialized markdown.

This plugin is built on mdast-util-to-markdown, which turns mdast syntax trees into a string. remark focusses on making it easier to transform content by abstracting such internals away.

unified is a project that transforms content with abstract syntax trees (ASTs). remark adds support for markdown to unified. mdast is the markdown AST that remark uses. This is a remark plugin that defines how mdast is turned into markdown.

When should I use this?

This plugin adds support to unified for serializing markdown. You can alternatively use remark instead, which combines unified, remark-parse, and this plugin.

You can combine this plugin with other plugins to add syntax extensions. Notable examples that deeply integrate with it are remark-gfm, remark-mdx, remark-frontmatter, remark-math, and remark-directive. You can also use any other remark plugin before remark-stringify.

If you want to handle syntax trees manually, you can use mdast-util-to-markdown.

Install

This package is ESM only. In Node.js (version 12.20+, 14.14+, or 16.0+), install with npm:

npm install remark-stringify

In Deno with Skypack:

import remarkStringify from 'https://cdn.skypack.dev/remark-stringify@10?dts'

In browsers with Skypack:

<script type="module">
  import remarkStringify from 'https://cdn.skypack.dev/remark-stringify@10?min'
</script>

Use

Say we have the following module example.js:

import {unified} from 'unified'
import rehypeParse from 'rehype-parse'
import rehypeRemark from 'rehype-remark'
import remarkStringify from 'remark-stringify'

main()

async function main() {
  const file = await unified()
    .use(rehypeParse)
    .use(rehypeRemark)
    .use(remarkStringify, {
      bullet: '*',
      fence: '~',
      fences: true,
      incrementListMarker: false
    })
    .process('<h1>Hello, world!</h1>')

  console.log(String(file))
}

Running that with node example.js yields:

# Hello, world!

API

This package exports no identifiers. The default export is remarkStringify.

`unified().use(remarkStringify[, options])`

Add support for serializing markdown. Options are passed to mdast-util-to-markdown: all formatting options are supported.

`options`

Configuration (optional).

`options.bullet`

Marker to use for bullets of items in unordered lists ('*', '+', or '-', default: '*').

`options.bulletOther`

Marker to use in certain cases where the primary bullet doesn’t work ('*', '+', or '-', default: depends). See mdast-util-to-markdown for more information.

`options.bulletOrdered`

Marker to use for bullets of items in ordered lists ('.' or ')', default: '.').

`options.bulletOrderedOther`

Marker to use in certain cases where the primary bullet for ordered items doesn’t work ('.' or ')', default: none). See mdast-util-to-markdown for more information.

`options.closeAtx`

Whether to add the same number of number signs (#) at the end of an ATX heading as the opening sequence (boolean, default: false).

`options.emphasis`

Marker to use for emphasis ('*' or '_', default: '*').

`options.fence`

Marker to use for fenced code ('`' or '~', default: '`').

`options.fences`

Whether to use fenced code always (boolean, default: false). The default is to use fenced code if there is a language defined, if the code is empty, or if it starts or ends in blank lines.

`options.incrementListMarker`

Whether to increment the counter of ordered lists items (boolean, default: true).

`options.listItemIndent`

How to indent the content of list items ('one', 'tab', or 'mixed', default: 'tab'). Either with the size of the bullet plus one space (when 'one'), a tab stop ('tab'), or depending on the item and its parent list ('mixed', uses 'one' if the item and list are tight and 'tab' otherwise).

`options.quote`

Marker to use for titles ('"' or "'", default: '"').

`options.resourceLink`

Whether to always use resource links (boolean, default: false). The default is to use autolinks (<https://example.com>) when possible and resource links ([text](url)) otherwise.

`options.rule`

Marker to use for thematic breaks ('*', '-', or '_', default: '*').

`options.ruleRepetition`

Number of markers to use for thematic breaks (number, default: 3, min: 3).

`options.ruleSpaces`

Whether to add spaces between markers in thematic breaks (boolean, default: false).

`options.setext`

Whether to use setext headings when possible (boolean, default: false). The default is to always use ATX headings (# heading) instead of setext headings (heading\n=======). Setext headings can’t be used for empty headings or headings with a rank of three or more.

`options.strong`

Marker to use for strong ('*' or '_', default: '*').

`options.tightDefinitions`

Whether to join definitions without a blank line (boolean, default: false). The default is to add blank lines between any flow (“block”) construct.

`options.handlers`

This option is a bit advanced as it requires knowledge of ASTs, so we defer to the documentation available in mdast-util-to-markdown.

`options.join`

This option is a bit advanced as it requires knowledge of ASTs, so we defer to the documentation available in mdast-util-to-markdown.

`options.unsafe`

This option is a bit advanced as it requires deep knowledge of markdown, so we defer to the documentation available in mdast-util-to-markdown.

Syntax

Markdown is serialized according to CommonMark but care is taken to format in such a way that the resulting markdown should work with most markdown parsers. Other plugins can add support for syntax extensions.

Syntax tree

The syntax tree format used in remark is mdast.

Types

This package is fully typed with TypeScript. An Options type is exported, which models the interface of accepted options.

Security

As markdown can be turned into HTML and improper use of HTML can open you up to cross-site scripting (XSS) attacks, use of remark can be unsafe. When going to HTML, you will likely combine remark with rehype, in which case you should use rehype-sanitize.

Use of remark plugins could also open you up to other attacks. Carefully assess each plugin and the risks involved in using them.

For info on how to submit a report, see our security policy.

Contribute

See contributing.md in remarkjs/.github for ways to get started. See support.md for ways to get help. Join us in Discussions to chat with the community and contributors.

This project has a code of conduct. By interacting with this repository, organization, or community you agree to abide by its terms.