remark

What is remark?

The remark npm package is a powerful, extensible Markdown processor built on the unified collective ecosystem. It allows for parsing, transforming, and compiling Markdown content with a focus on syntax trees. Remark can be used for a variety of tasks such as linting Markdown, transforming the syntax for different purposes, or extracting metadata from documents.

What are remark's main functionalities?

Parsing Markdown to Syntax Trees

This feature allows users to parse Markdown content into an abstract syntax tree (AST), enabling programmatic analysis and manipulation of the content.

const remark = require('remark');
const markdown = 'Some **Markdown** text.';
remark().parse(markdown);

Transforming Syntax Trees

With this feature, users can transform the syntax tree generated from Markdown content. For example, converting the tree to HTML by using the remark-html plugin.

const remark = require('remark');
const html = require('remark-html');
const markdown = 'Some **Markdown** text.';
remark().use(html).processSync(markdown).toString();

Linting Markdown

This feature enables users to lint their Markdown content for style and syntax issues, ensuring consistency and quality in their Markdown files.

const remark = require('remark');
const recommended = require('remark-preset-lint-recommended');
const report = require('vfile-reporter');

remark().use(recommended).process('_Emphasis_ and **importance**', (err, file) => {
  console.error(report(err || file));
});

Other packages similar to remark

markdown-it

markdown-it is a fast and extensible Markdown parser that can render HTML. It is similar to remark in its extensibility but focuses more on speed and adherence to the CommonMark specification without an emphasis on abstract syntax trees.

showdown

showdown is another Markdown to HTML converter that can run both in the browser and on the server. Unlike remark, which is built around a plugin ecosystem and AST manipulation, showdown focuses on configurability and extension through a different type of extension mechanism.

marked

marked is a low-level Markdown compiler for parsing Markdown without caching or blocking for files. It is designed for speed and is simpler in scope compared to remark, which offers a broader range of processing capabilities through its plugins and unified ecosystem.

README

remark

unified processor to parse and compile Markdown. Powered by plugins. Part of the unified collective.

• API by unified
• Parses Markdown to a syntax tree with remark-parse
• mdast syntax tree
• Plugins transform the tree
• Stringifies syntax trees to Markdown with remark-stringify

Don’t need the parser? Or compiler? That’s OK: use unified directly.

Sponsors

🥇 ZEIT

🥇 Gatsby

🥇 Netlify

Holloway

You?

Read more about the unified collective on Medium »

Install

npm:

npm install remark

Use

See unified for more examples »

Common example

This example lints Markdown and turns it into HTML.

var remark = require('remark')
var recommended = require('remark-preset-lint-recommended')
var html = require('remark-html')
var report = require('vfile-reporter')

remark()
  .use(recommended)
  .use(html)
  .process('## Hello world!', function(err, file) {
    console.error(report(err || file))
    console.log(String(file))
  })

Yields:

1:1  warning  Missing newline character at end of file  final-newline  remark-lint

⚠ 1 warning

<h2>Hello world!</h2>

Settings through data

This example prettifies Markdown and configures remark-parse and remark-stringify through data.

var remark = require('remark')

remark()
  .data('settings', {commonmark: true, emphasis: '*', strong: '*'})
  .process('_Emphasis_ and __importance__', function(err, file) {
    if (err) throw err
    console.log(String(file))
  })

Yields:

*Emphasis* and **importance**

Settings through a preset

This example prettifies Markdown and configures remark-parse and remark-stringify through a preset.

var remark = require('remark')

remark()
  .use({
    settings: {commonmark: true, emphasis: '*', strong: '*'}
  })
  .process('_Emphasis_ and __importance__', function(err, file) {
    if (err) throw err
    console.log(String(file))
  })

Yields:

*Emphasis* and **importance**

API

See unified for API docs »

Security

As Markdown is sometimes used for HTML, and improper use of HTML can open you up to a cross-site scripting (XSS) attack, use of remark can also be unsafe. When going to HTML, use remark in combination with the rehype ecosystem, and use rehype-sanitize to make the tree safe.

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

Contribute

See contributing.md in remarkjs/.github for ways to get started. See support.md for ways to get help. Ideas for new plugins and tools can be posted in remarkjs/ideas.

A curated list of awesome remark resources can be found in awesome remark.

This project has a Code of Conduct. By interacting with this repository, organisation, or community you agree to abide by its terms.

License

MIT © Titus Wormer