Combaine promise with generator

gistfile1.js

//Combaine promise with generator

function *getUrl(url) {
  try {
    var response = yield getReq(url).then(function(fb) {
      console.log('feedback!!!');
      console.log(fb);
      return fb;
	},
    function(e) {
      console.log(e);
      return e;
    });
  } catch(e) {
    console.log(e);
  }

  return 'done';
}

function getReq(url) {
  return new Promise(function(res,rej) {
        xhr = new XMLHttpRequest();
        xhr.open('GET', url);
        xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
        xhr.onload = function() {
            if (xhr.status === 200) {
                res(xhr.responseText);
            }
            else if (xhr.status !== 200) {
                rej('error');
            }
        };
       xhr.send(null);
  });
}

var it = getUrl('www.google.com');
//it.next();
//it.next().value;