ArrayPromise for array-like fun with YUI promises

gistfile1.js

function ArrayPromise() {
  ArrayPromise.superclass.constructor.apply(this, arguments);
}
Y.extend(ArrayPromise, Y.Promise);

Y.Array.each(['each', 'map', 'filter', 'some', 'every', 'reject'], function (method) {
  ArrayPromise.prototype[method] = function () {
    var args = Array.prototype.slice.call(arguments);
    return this.then(function (results) {
      return Y.Array[method].apply(Y.Array, [results].concat(args));
    });
  };
});

var __batch = Y.batch;
Y.batch = function () {
  var promise = __batch.apply(Y, arguments);
  return new ArrayPromise(function (resolve, reject) {
    promise.then(resolve, reject);
  });
};

function async(args, fn) {
  return Y.batch.apply(Y, Y.Array.map(args, function (arg) {
    return new Y.Promise(function (resolve, reject) {
      fn(arg, function (err, result) {
        if (err) {
          reject(err);
        } else {
          resolve(result);
        }
      });
    });
  });
}

async(['foo.php', 'bar.php', 'baz.php'], Y.io).filter(function (result) {
  return result.indexOf('foo') > 1;
}).each(function (result) {
  console.log(result);
});