# remark-directive

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[**remark**][remark] plugin to support the [generic directives proposal][prop]
(`:cite[smith04]`, `::youtube[Video of a cat in a box]{v=01ab2cd3efg}`, and
such).

## Important!

This plugin is made for the new parser in remark
([`micromark`](https://github.com/micromark/micromark),
see [`remarkjs/remark#536`](https://github.com/remarkjs/remark/pull/536)).
Use this plugin for remark 13+.

## Install

This package is [ESM only](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c):
Node 12+ is needed to use it and it must be `import`ed instead of `require`d.

[npm][]:

```sh
npm install remark-directive
```

## Use

Say we have the following file, `example.md`:

```markdown
:::main{#readme}

Lorem:br
ipsum.

::hr{.red}

A :i[lovely] language know as :abbr[HTML]{title="HyperText Markup Language"}.

:::
```

And our module, `example.js`, looks as follows:

```js
import {readSync} from 'to-vfile'
import {reporter} from 'vfile-reporter'
import {unified} from 'unified'
import remarkParse from 'remark-parse'
import remarkDirective from 'remark-directive'
import remarkRehype from 'remark-rehype'
import rehypeFormat from 'rehype-format'
import rehypeStringify from 'rehype-stringify'
import {visit} from 'unist-util-visit'
import {h} from 'hastscript'

const file = readSync('example.md')

unified()
  .use(remarkParse)
  .use(remarkDirective)
  .use(customPlugin)
  .use(remarkRehype)
  .use(rehypeFormat)
  .use(rehypeStringify)
  .process(file)
  .then((file) => {
    console.error(reporter(file))
    console.log(String(file))
  })

// This plugin is just an example! You can handle directives however you please!
function customPlugin() {
  return (tree) => {
    visit(tree, (node) => {
      if (
        node.type === 'textDirective' ||
        node.type === 'leafDirective' ||
        node.type === 'containerDirective'
      ) {
        const data = node.data || (node.data = {})
        const hast = h(node.name, node.attributes)

        data.hName = hast.tagName
        data.hProperties = hast.properties
      }
    })
  }
}
```

Now, running `node example` yields:

```txt
example.md: no issues found
```

```html
example.md: no issues found
<main id="readme">
  <p>Lorem<br>ipsum.</p>
  <hr class="red">
  <p>A <i>lovely</i> language know as <abbr title="HyperText Markup Language">HTML</abbr>.</p>
</main>
```

## API

This package exports no identifiers.
The default export is `remarkDirective`.

### `unified().use(remarkDirective)`

Configures remark so that it can parse and serialize directives.
Doesn’t handle the directives: [create your own plugin][create-plugin] to do
that.
See the [micromark extension for the syntax][syntax] and the
[mdast utility for the syntax tree][syntax-tree].

## Security

Use of `remark-directive` does not involve [**rehype**][rehype]
([**hast**][hast]) or user content so there are no openings for [cross-site
scripting (XSS)][xss] attacks.

## Related

*   [`remark-gfm`](https://github.com/remarkjs/remark-gfm)
    — GFM
*   [`remark-github`](https://github.com/remarkjs/remark-github)
    — Autolink references like in GitHub issues, PRs, and comments
*   [`remark-footnotes`](https://github.com/remarkjs/remark-footnotes)
    — Footnotes
*   [`remark-frontmatter`](https://github.com/remarkjs/remark-frontmatter)
    — Frontmatter (YAML, TOML, and more)
*   [`remark-math`](https://github.com/remarkjs/remark-math)
    — Math

## Contribute

See [`contributing.md`][contributing] in [`remarkjs/.github`][health] for ways
to get started.
See [`support.md`][support] for ways to get help.

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

## License

[MIT][license] © [Titus Wormer][author]

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[chat]: https://github.com/remarkjs/remark/discussions

[npm]: https://docs.npmjs.com/cli/install

[health]: https://github.com/remarkjs/.github

[contributing]: https://github.com/remarkjs/.github/blob/HEAD/contributing.md

[support]: https://github.com/remarkjs/.github/blob/HEAD/support.md

[coc]: https://github.com/remarkjs/.github/blob/HEAD/code-of-conduct.md

[license]: license

[author]: https://wooorm.com

[remark]: https://github.com/remarkjs/remark

[xss]: https://en.wikipedia.org/wiki/Cross-site_scripting

[rehype]: https://github.com/rehypejs/rehype

[hast]: https://github.com/syntax-tree/hast

[prop]: https://talk.commonmark.org/t/generic-directives-plugins-syntax/444

[create-plugin]: https://unifiedjs.com/learn/guide/create-a-plugin/

[syntax]: https://github.com/micromark/micromark-extension-directive#syntax

[syntax-tree]: https://github.com/syntax-tree/mdast-util-directive#syntax-tree