Sprint Challenge: JavaScript Fundamentals

This challenge allows you to practice the concepts and techniques learned over the past week and apply them in a survey of problems. This Sprint explored JavaScript Fundamentals. During this Sprint, you studied variables, functions, object literals, arrays, this keyword, prototypes, and class syntax. In your challenge this week, you will demonstrate proficiency by completing a survey of JavaScript problems.

Read these instructions carefully. Understand exactly what is expected before starting this Sprint Challenge.

This is an individual assessment. All work must be your own. Your challenge score is a measure of your ability to work independently using the material covered through this sprint. You need to demonstrate proficiency in the concepts and objectives introduced and practiced in preceding days.

You are not allowed to collaborate during the Sprint Challenge. However, you are encouraged to follow the twenty-minute rule and seek support from your PM and Instructor in your cohort help channel on Slack. Your work reflects your proficiency in JavaScript fundamentals.

You have three hours to complete this challenge. Plan your time accordingly.

Commit your code regularly and meaningfully. This helps both you (in case you ever need to return to old code for any number of reasons) and your project manager.

You will notice there are several JavaScript files being brought into the index.html file. Each of those files contain JavaScript problems you need to solve. If you get stuck on something, skip over it and come back to it later.

In meeting the minimum viable product (MVP) specifications listed below, you should have a console full of correct responses to the problems given.

Demonstrate your understanding of this week's concepts by answering the following free-form questions.

Edit this document to include your answers after each question. Make sure to leave a blank line above and below your answer so it is clear and easy to read by your project manager

1. Describe the biggest difference between .forEach & .map.

forEach() it’s a method made for applying a function to every element in a array. Map() is similar to it, but has the great difference that will return a new array, leaving the original array unchanged.

2. What is the difference between a function and a method?

A function is a piece of code that act like a small program: it could (or not) take some arguments, then it “do something” and then return some values (or have some kind of “side effects”). A method is a specific kind of function, that is associated with an object. For this reason it cannot “exists” without the object itself. For this reason is also scoped inside the object (it can’t access outside data)

3. What is closure?

Closure is an important concept in JavaScript. Basically a function nested inside another function can access all the variables inside the parent(s) and inside itself (has a bigger scope).
Instead the parent function can’t access the children(s) variables. This permit us to have huge advantages scoping our variables properly.

4. Describe the four rules of the 'this' keyword.

The four rules of “this” are: Global binding: when “this” is applied to a function in the global scope, it’s bound to the global object/window object. Implicit binding: when “this” is used as a method, it’s bound to the object itself. New binding: when an object is instantiated with the word “new”, “this” is bound with the newly instantiated object . Explicit binding: when .apply, .call or .bind are used “this” is explicitly bound with the object you are applying the method to.

5. Why do we need super() in an extended class?

super() is a method that needs to be used inside our subclass constructor and permits us to inherit all the properties from the parent class. We use them to create subclasses without the need of using .call().

• Fork the project into your GitHub user account
• Clone the forked project into a directory on your machine
• Create a pull request before you start working on the project requirements. You will continuously push your updates throughout the project.
• You are now ready to build this project with your preferred IDE

Your finished project must include all of the following requirements:

Pro tip for this challenge: If something seems like it isn't working locally, copy and paste your code up to codepen and take another look at the console.

Test your knowledge of objects and arrays.

• Use the objects-arrays.js link to get started. Read the instructions carefully!

This challenge takes a look at callbacks and closures as well as scope.

• Use the functions.js link to get started. Read the instructions carefully!

Create constructors, bind methods, and create cuboids in this prototypes challenge.

• Use the prototypes.js link to get started. Read the instructions carefully!

Once you have completed the prototypes challenge, it's time to convert all your hard work into classes.

• Use the classes.js link to get started. Read the instructions carefully!

In your solutions, it is essential that you follow best practices and produce clean and professional results. Schedule time to review, refine, and assess your work and perform basic professional polishing including spell-checking and grammar-checking on your work. It is better to submit a challenge that meets MVP than one that attempts too much and does not.

There are a few stretch problems found throughout the files, don't work on them until you are finished with MVP requirements!