Chapter-14.md

Implement resolve and reject as static functions

Having some static functions can make our function handier.

Start with the resolve function. This function takes a value and returns a thenable object from the asyncController.

asyncController.resolve = function (value) {

  function borrowResolve(resolve) {
    resolve(value);
  }

  return asyncController(borrowResolve);
}

It's simple and we resolve the value straight away.

The implementation of the reject function is also the same, but this time we use the reject parameter of the borrowFunction.

asyncController.reject = function (err) {

  function borrowReject(resolve, reject) {
    reject(err);
  }

  return asyncController(borrowReject);
}

And to finish this tutorial, you can just change the name of the asyncController function to Promise.

Congratulations. You have implemented and also understood the promise pattern.