remark
unified processor with support for parsing markdown input and serializing markdown as output.
Contents
- What is this?
- When should I use this?
- Install
- Use
- API
- Examples
- Syntax
- Syntax tree
- Types
- Compatibility
- Security
- Contribute
- Sponsor
- License
What is this?
This package is a unified processor with support for parsing markdown input and serializing markdown as output by using unified with remark-parse
and remark-stringify
.
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. Please see the monorepo readme for what the remark ecosystem is.
When should I use this?
You can use this package when you want to use unified, have markdown as input, and want markdown as output. This package is a shortcut for unified().use(remarkParse).use(remarkStringify)
. When the input isn’t markdown (meaning you don’t need remark-parse
) or the output is not markdown (you don’t need remark-stringify
), it’s recommended to use unified directly.
When you want to inspect and format markdown files in a project on the command line, you can use remark-cli
.
Install
This package is ESM only. In Node.js (version 12.20+, 14.14+, or 16.0+), install with npm:
npm install remark
In Deno with esm.sh
:
import {remark} from 'https://esm.sh/remark@14'
In browsers with esm.sh
:
<script type="module">
import {remark} from 'https://esm.sh/remark@14?bundle'
</script>
Use
Say we have the following module example.js
:
import {remark} from 'remark'
import remarkGfm from 'remark-gfm'
import remarkToc from 'remark-toc'
main()
async function main() {
const file = await remark()
.use(remarkGfm)
.use(remarkToc)
.process('# Hi\n\n## Table of contents\n\n## Hello\n\n*Some* ~more~ _things_.')
console.error(String(file))
}
Running that with node example.js
yields:
# Hi
## Table of contents
* [Hello](#hello)
## Hello
*Some* ~~more~~ *things*.
API
This package exports the following identifier: remark
. There is no default export.
remark()
Create a new (unfrozen) unified processor that already uses remark-parse
and remark-stringify
and you can add more plugins to. See unified
for more information.
Examples
Example: checking markdown
The following example checks that markdown code style is consistent and follows some best practices:
import {reporter} from 'vfile-reporter'
import {remark} from 'remark'
import remarkPresetLintConsistent from 'remark-preset-lint-consistent'
import remarkPresetLintRecommended from 'remark-preset-lint-recommended'
main()
async function main() {
const file = await remark()
.use(remarkPresetLintConsistent)
.use(remarkPresetLintRecommended)
.process('1) Hello, _Jupiter_ and *Neptune*!')
console.error(reporter(file))
}
Yields:
1:1 warning Missing newline character at end of file final-newline remark-lint
1:1-1:35 warning Marker style should be `.` ordered-list-marker-style remark-lint
1:4 warning Incorrect list-item indent: add 1 space list-item-indent remark-lint
1:25-1:34 warning Emphasis should use `_` as a marker emphasis-marker remark-lint
⚠ 4 warnings
Example: passing options to remark-stringify
When you use remark-stringify
manually you can pass options to use
. Because remark-stringify
is already used in remark
, that’s not possible. To define options for remark-stringify
, you can instead pass options to data
:
import {remark} from 'remark'
main()
async function main() {
const file = await remark()
.data('settings', {bullet: '*', setext: true, listItemIndent: 'one'})
.process('# Moons of Neptune\n\n- Naiad\n- Thalassa\n- Despine\n- …')
console.log(String(file))
}
Yields:
Moons of Neptune
================
* Naiad
* Thalassa
* Despine
* …
Syntax
Markdown is parsed and serialized according to CommonMark. 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. There are no extra exported types.
Compatibility
Projects maintained by the unified collective are compatible with all maintained versions of Node.js. As of now, that is Node.js 12.20+, 14.14+, and 16.0+. Our projects sometimes work with older versions, but this is not guaranteed.
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.
Sponsor
Support this effort and give back by sponsoring on OpenCollective!
Vercel | Motif | HashiCorp | GitBook | Gatsby | |||||
Netlify![]() | Coinbase | ThemeIsle | Expo | Boost Note![]() | Markdown Space![]() | Holloway | |||
You? |