markdown⁠-⁠it⁠-⁠v

A custom markdown⁠-⁠it renderer that outputs virtual DOM.

Motivation

Why prefer virtual DOM to innerHTML?

• Better integration with modern JavaScript frameworks like Vue and React.
• Better performance for real-time preview of large Markdown document. Thanks to the diff algorithm of virtual DOM, the real DOM modification can be minimized.

Why markdown⁠-⁠it⁠-⁠v

• markdown⁠-⁠it itself has great performance.

• markdown⁠-⁠it⁠-⁠v is a markdown⁠-⁠it plugin and can be integrated seamlessly.

• markdown⁠-⁠it⁠-⁠v supports four schemes of output:

  • Vue virtual DOM
  • React virtual DOM
  • Browser’s real DOM
  • HTML string

Installation

$ npm install markdown-it markdown-it-v@npm:@ruihe774/markdown-it-v@3 --save

Usage

Setup

markdown⁠-⁠it⁠-⁠v is a plugin of markdown⁠-⁠it:

import MarkdownIt from 'markdown-it'
import MarkdownItVPlugin from 'markdown-it-v'

const md = MarkdownIt().use(MarkdownItVPlugin)

If you're using TypeScript, you can convert the enhanced markdown⁠-⁠it instance to the modified interface:

import MarkdownIt from 'markdown-it'
import MarkdownItVPlugin from 'markdown-it-v'
import type { MarkdownItV } from 'markdown-it-v'

const md = MarkdownIt().use(MarkdownItVPlugin) as unknown as MarkdownItV

Render

After setup, the render() method will return a StreamDom object — a kind of virtual DOM implemented by markdown⁠-⁠it⁠-⁠v itself:

let sdom = md.render('The *quick* brown fox _jumps_ over the **lazy** dog.')

Convert

Unfortunately you cannot use StreamDom in other places and it doesn’t implement a diff algorithm. You must convert it to final output:

let vueVDom   = sdom.toVue(Vue.h)
let reactVDom = sdom.toReact(React.createElement)
let realDom   = sdom.toNative(document.createElement.bind(document))    // `.bind()` is necessary
let htmlStr   = sdom.toHTML()

Integrate with JS Frameworks

Vue component (e.g. without JSX):

Vue.defineComponent({
    // in a Vue component
    props: ['source'],
    computed: {
        sDom() {
            return md.render(this.source)
        }
    },
    render() {
        const { h } = Vue
        return h('div', null, this.sDom.toVue(h))
    }
})

React component (e.g. with JSX):

function Markdown({ source }) {
    // in a React component
    const h = React.createElement
    const sdom = useMemo(() => md.render(source), [source])
    return <div>{sdom.toReact(h)}</div>
}

Vanilla:

const container = document.createElement('div')
container.append(...sdom.toNative(document.createElement.bind(document)))

Changelog

• 3.0.1

  • Fix highlight fence
  • Fix React refs

• 3.0.0

  • Return (string | HTMLElement)[] in sdom.toNative; do not require whole document object

• 2.0.0

  • Major refactor
  • Migrate to TypeScript
  • Upgrade all packages

• 1.2.0

  • Drop css-tree

• 1.1.1

  • Add ES6 module output

• 1.1.0

  • Adds highlightNoWrappingEls (#1) by @laosb

• 1.0.0-beta.1

  • No change

• 1.0.0-alpha.2

  • Use _.fromPairs in lodash

• 1.0.0-alpha.1

  • Initial release