Step 2

regex-html-2.js

function parse_content(cursor) {
	let run = true;
	while (run && input.length > 0) {
		// Parse an open tag
		const success = pull(/^<([a-zA-Z][a-zA-Z0-9\-]*)>/, tag => {
			const new_tag = { tag, attributes: {}, children: [] };
			cursor.children.push(new_tag);
			parse_content(new_tag);
		}) ||
		// Parse close tag
		pull(/^<\/([a-zA-Z][a-zA-Z0-9\-]*)>/, tag => {
			if (cursor.tag !== tag) {
				throw new Error("Unmatched close tag");
			}
			run = false;
		});
		if (!success) {
			throw new Error("Parse error");
		}
	}
}