js template engine

gistfile1.txt

const REGEX_REPLACE_PATTERN = /<%([^%>]+)?%>/g 
const REGEX_EXECUTION_KEYWORDS = /(^( )?(if|for|else|switch|case|break|{|}))(.*)?/g

const TemplateEngine = function(html, options) {
	let code = 'var r=[];\n';
	let cursor = 0;
	let match;

	var add = function(line, js) {
		if (js) {
			code += line.match(REGEX_EXECUTION_KEYWORDS) ? line + '\n' : 'r.push(' + line + ');\n';
		} else {
			code += line !== '' ? 'r.push("' + line.replace(/"/g, '\\"') + '");\n' : '';
		}

		return add;
	}

	while(match = REGEX_REPLACE_PATTERN.exec(html)) {
		const part = html.slice(cursor, match.index);
		add(part)(match[1], true);
		cursor = match.index + match[0].length;
	}

	add(html.substr(cursor, html.length - cursor))
	code += 'return r.join("");';
	return new Function(code).apply(options)
}

var template =
'My skills:' +
'<%if(this.showSkills) {%>' +
    '<%for(var index in this.skills) {%>' +
    '<a href="#"><%this.skills[index]%></a>' +
    '<%}%>' +
'<%} else {%>' +
    '<p>none</p>' +
'<%}%>';

console.log(TemplateEngine(template, {
    skills: ["js", "html", "css"],
    showSkills: true
}));