Asynchronous JavaScript

Promises

100

JavaScript objects that represent the eventual result of an asynchronous operation.

Promises

200

The two possible outcomes of a promise that has been settled.

resolved and rejected

300

Used with a success handler callback containing the logic for what should happen if a promise resolves.

.then()

400

Used with a failure handler callback containing the logic for what should happen if a promise rejects.

.catch()

500

Data type of the fulfilled value of Promise.all() ?

an Array

Callbacks & Functions

100

A function that is passed as an argument to another function.

A callback function

200

True or False: callback functions can handle both synchronous and asynchronous operations.

True

300

How we would pass callback into myFunction as a callback function.

const callback = () => {. . .};

const myFunction = callback => {. . .};

myFunction(callback);

400

The amount of time that would pass before the anonymous callback function would queue for execution.

setTimeout(()=>console.log("Hello learners!"), 11000);

11 seconds

500

A term for the situation a programmer finds themself in when they nest too many callback functions inside of one another like the following example:

_{firstRequest(function(response) {} 

   _{secondRequest(response,function(nextResponse) {}  

       _{thirdRequest(nextResponse, function(finalResponse) {}

           _{console.log('Final response: ' + finalResponse);}

       _{}, failureCallback);} 

   _{}, failureCallback);}

_{}, failureCallback);}

Callback Hell

Async Await

100

The keyword that indicates an asynchronous function?

async

200

An operator used only inside of an async function that halts the execution of a function until a given promise is no longer pending and returns the resolved value of the promise.

await

300

In order to use the await keyword, we have to wrap it within this kind of function.

Asynchronous

400

The result of the following code:

async function myFunction() {
  return 'hello world';
}
myFunction()
.then((resolvedValue) => {
  console.log(resolvedValue);
})

'hello world' is printed to the console

500

The two possible {} block statements that follow a try block statement (One of the two is required, but there are two possibilities)

Catch and finally

Requests

100

What API stands for.

Application Programming Interface

200

The modern API for making a request from our JavaScript.

The fetch() API

300

Type of HTTP method is used to read or retrieve a resource from an API.

GET

400

The type of data that the GET and POST requests send and receive.

Objects

500

The two possible parameters to a fetch statement (First one is required, second one is optional)

The URL, and options or init object

Potpourri

100

What the data-transfer format JSON stands for.

JavaScript Object Notation

200

A particular style of JavaScript (such as callbacks, promises, and async/await), that allows you to perform long network requests without blocking the main thread.

Asynchronous

300

What HTTP stands for

Hypertext Transfer Protocol

400

Built-in Node JavaScript function that sets a timer which queues a function or piece of code for execution when the timer expires

setTimeout()

500

What an async function returns

async function example() { }

A promise