let template = "\<div id='div'\>This is <%this.msg.one%>, say <%this.words%>\<\/div\>";
        template+= "<%for(var i = 0; i<this.last.length; i++){%>"
        template+= "<%this.last[i]%> !"
        template+= "<%}%>"

    function render(tpl, data){
      let pattern = /<%([^%>]+)?%>/g,
          keyRegx = /(^( )?(if|for|else|switch|case|break|{|}))(.*)?/g,
          code = "var r = [];\n", cursor = 0
      /* var r = [];
       * r.push(prevString);
       * r.push(matchWord);
       * r.push(lastString);
       * return r.join("");
       */
      let add = (line, isJs) => {
        code += isJs ?
            line.match(keyRegx) ? line+"\n" : 'r.push('+line+');\n'
            : 'r.push("'+line.replace(/"/g, '\\"')+'");\n';
      }

      while(match = pattern.exec(tpl)){
        add(tpl.slice(cursor, match.index))
        add(match[1], true)
        cursor = match.index + match[0].length
        // tpl = tpl.replace(match[0], data[match[1]])
      }
      add(tpl.substr(cursor, tpl.length - cursor))
      code += 'return r.join("");'
      console.log(code)
      return (new Function(code.replace(/[\r\n\t]/g, ''))).call(data)
    }

    document.body.innerHTML = render(template, {
      msg: { one: "div"},
      words: "hi",
      last: ["bye", "bye"]
    })