jsonml2mithril.js

import type from 'type-of-is'

export default function parse( input ){
	if( type( input, String ) ){
		return input
	}
	else if( type( input[ 0 ], Array ) ){
		return input.map( parse )
	}

	return input.reduce( ( node, item, index ) => {
		switch ( type( item ) ){
			case String :
				if( index === 0 ){
					node.tag = item
				}
				else {
					node.children.push( item )
				}
				break
			case Array :
				node.children.push( parse( item ) )
				break
			case Object :
				node.attrs = item
		}

		return node
	}, {
		attrs    : {},
		children : []
	} )
}

markdown2jsonml.js

import md from 'markdown'

const API = md.markdown

export default input => API.toHTMLTree( input )

markdown2mithril.js

import jsonml2m  from './jsonml2mithril'
import md2jsonml from './markdown2jsonml'

export default markdown => jsonml2m( md2jsonml( markdown ) )

package.json

{
  "main": "markdown2mithril.js",
  "scripts": {
    "build": "browserify markdown2mithril.js -t babelify"
  },
  "devDependencies": {
    "babelify": "^6.0.1",
    "browserify": "^9.0.7"
  },
  "dependencies" : {
    "markdown": "^0.5.0",
    "mithril": "^0.1.34",
    "type-of-is": "^3.4.0"
  },
  "browserify": {
    "transform": [
      "babelify"
    ]
  }
}