``js server
/ START - Rocket auto generated - do not touch /
export const sourceRelativeFilePath = '30--tools/20--markdown-javascript/10--overview.rocket.md';
// prettier-ignore
import { html, layout, setupUnifiedPlugins, components, openGraphLayout } from '../../recursive.data.js';
export { html, layout, setupUnifiedPlugins, components, openGraphLayout };
export async function registerCustomElements() {
// server-only components
// prettier-ignore
customElements.define('rocket-social-link', await import('@rocket/components/social-link.js').then(m => m.RocketSocialLink));
// prettier-ignore
customElements.define('rocket-header', await import('@rocket/components/header.js').then(m => m.RocketHeader));
// prettier-ignore
customElements.define('rocket-main-docs', await import('@rocket/components/main-docs.js').then(m => m.RocketMainDocs));
// prettier-ignore
customElements.define('rocket-content-area', await import('@rocket/components/content-area.js').then(m => m.RocketContentArea));
// hydrate-able components
// prettier-ignore
customElements.define('rocket-search', await import('@rocket/search/search.js').then(m => m.RocketSearch));
// prettier-ignore
customElements.define('rocket-drawer', await import('@rocket/components/drawer.js').then(m => m.RocketDrawer));
}
export const needsLoader = true;
/ END - Rocket auto generated - do not touch /

export const title = 'Markdown JavaScript';
export const subTitle = 'Executable JavaScript in markdown by annotating code blocks';
`

Overview

`js client
import '@mdjs/mdjs-story/define';
import '@mdjs/mdjs-preview/define';
import { html } from '@mdjs/mdjs-story';
`

Markdown JavaScript (mdjs) is a format that allows you to use JavaScript with Markdown, to create interactive demos. It does so by "annotating" JavaScript that should be executed in Markdown.

To annotate we use a code block with js client.

``md
`js client
// execute me
`
``

Web Components

One very good use case for that can be web components.
HTML already works in Markdown so all you need is to load a web components definition file.

You could even do so within the same Markdown file.

``md


This is my-card

Here's an example of the component:

`html preview-story



Hello world!


Click me!

`
``

You can even execute some JavaScript:

``md


This is my-el

`js client
import { LitElement, html } from 'https://unpkg.com/lit-element?module';

class MyEl extends LitElement {
render() {
this.innerHTML = '

I am alive

';
}
}

customElements.define('my-el', MyEl);
`
``

Demo Support (Story)

mdjs comes with some additional helpers you can choose to import:

``md
`js client
import '@mdjs/mdjs-story/define';
import '@mdjs/mdjs-preview/define';
`
``

Once loaded you can use them like so:

$3

The code snippet will actually get executed at that place and you will have a live demo

``md
`js story
export const JsStory = () => html JS Story ;
`
``

``md
`html story
HTML Story
`
``

#### Full Code Support

``md
`js story
export const JsStory = () => {
const calculateSomething = 12;
return html
Something: \\${calculateSomething}}">JS Story
;
};
`
``

$3

Will become a live demo wrapped in a container with a show code button.

``md
`js preview-story
export const JsPreviewStory = () => html JS Preview Story ;
`
``

``md
`html preview-story
HTML Preview Story
`
``

Here is a live example from demo-wc-card.

`js preview-story
import 'demo-wc-card/demo-wc-card.js';
export const header = () => {
return html ;
};
`

`js story-code
// not defined for android
`

`js story-code
// not defined for ios
`

#### Story Code

If your preview is followed by a code blocks marked as story-code then those will be shown when switching between multiple platforms

``md
`js preview-story
// will be visible when platform web is selected
export const JsPreviewStory = () => html JS Preview Story ;
`

`xml story-code

android:id="@+id/demoWcCard"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Android Code"
style="@style/Widget.FooComponents.Demo.Wc.Card"
/>
`

`swift story-code
// will be visible when platform ios is selected
import DemoWc.Card

let card = DemoWcButton()
`
``

See it in action by opening up the code block and switching platforms

`js preview-story
// will be visible when platform web is selected
export const JsPreviewStory = () => html JS Preview Story ;
`

`xml story-code

android:id="@+id/demoWcCard"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Android Code"
style="@style/Widget.FooComponents.Demo.Wc.Card"
/>
`

`swift story-code
// will be visible when platform ios is selected
import DemoWc.Card

let card = DemoWcButton()
`

Supported Systems

$3

Please check out @open-wc/demoing-storybook for a fully integrated setup.

It includes storybook-addon-markdown-docs which uses mdjs under the hood.

$3

See live demos directly inside GitHub pages, Markdown files, issues, pull requests...

Please check out mdjs-viewer.

Build mdjs

$3

mdjs offers two more "basic" integrations

#### mdjsDocPage

Creates a full blown HTML page by passing in the Markdown.

`js
const { mdjsDocPage } = require('@mdjs/core');

const page = await mdjsDocPage(markdownString);
/*

... // load styles/components for mdjs, start stories



Some Markdown




*/
`

#### mdjsProcess

Pass in multiple Markdown documents and you get back all the JavaScript code and rendered HTML.

`js
const { mdjsProcess } = require('@mdjs/core');

const data = await mdjsProcess(markdownString);
console.log(data);
/*
{
jsCode: "
import '@mdjs/mdjs-story/mdjs-story.js';
...
",
html: '

Markdown One

',
}
*/
`

$3

mdjs is build to be integrated within the unifiedjs system.

`js
const unified = require('unified');
const markdown = require('remark-parse');
const htmlStringify = require('remark-html');
const mdjsParse = require('@mdjs/core');

const parser = unified().use(markdown).use(mdjsParse).use(htmlStringify);
const result = await parser.process(body);
const { jsCode } = result.data;
console.log(result.contents);
//

This is my-el>


//
console.log(jsCode);
// customElements.define('my-el', class extends HTMLElement {
// ...
``