Step 1: Harness for a regex based recursive descent HTML parser.

regex-html-1.js

export default function parse_html(input) {
	const root = { children: [] };
	function pull(regex, handler = () => {}) {
		const match = regex.exec(input);
		if (match !== null) {
			const [full_match, ...captures] = match;
			input = input.substr(full_match.length);
			handler(...captures);
			return true;
		} else {
			return false;
		}
	}
	function parse_content(cursor) {
		
	}
	parse_content(root);
	return root.children;
}