While循环与承诺

我会用一个对象包装值。这样，您可以拥有一个

done

// fn should return an object like// {//   done: false,//   value: foo// }function loop(promise, fn) {  return promise.then(fn).then(function (wrapper) {    return !wrapper.done ? loop(Q(wrapper.value), fn) : wrapper.value;  });}loop(Q.resolve(1), function (i) {  console.log(i);  return {    done: i > 10,    value: i++  };}).done(function () {  console.log('done');});