[V3] Implement new Concept Exercise: classes-intro

[rishiosaur]

This issue describes how to implement the class concept exercise for the JavaScript track.

Getting started

Please please please read the docs before starting. Posting PRs without reading these docs will be a lot more frustrating for you during the review cycle, and exhaust Exercism's maintainers' time. So, before diving into the implementation, please read up on the following documents:

• The features of v3.
• Rationale for v3.
• What are concept exercise and how they are structured?

Please also watch the following video:

• The Anatomy of a Concept Exercise.

Goal

This exercise's goal is to teach the student about the function of classes in Javascript, why they exist, and how to implement them.

Learning objectives

• Understand the constructor function
• Understand how this works
• Know how to effectively create prototypal properties

Out of scope

• The new keyword
• Initializing classes (this exercise will only teach students how to implement classes in this exercise, not how to use them).
• Factory functions
• Class expressions (declaring a class with a var statement)
• Static properties & static methods
• extends keyword
• Class inheritance with super

Concepts

• Creating private properties in the constructor function
• Creating public functions that consume the properties defined in the constructor
• Using this to access class-wide properties

Prerequisites

• booleans
• strings
• functions
• objects

Resources to refer to

Hints

• [How to use this to access class properties][http://test.com]
• Using this in methods on the class prototype

After

• Function.prototype.bind
• Factory Functions
• Static Methods

Representer

No changes required

Analyzer

No changes required

Implementing

See the implementation guide for JavaScript for more detail.

Help

If you have any questions while implementing the exercise, please post the questions as comments in this issue.

[rishiosaur]

I'll be creating a new branch on my fork for this.

[SleeplessByte]

Nice! I'm excited about this.

I'm guessing you'll initialize classes in the tests, but not in the user code, so that they don't need to learn about new etc?

• Will you teach constructors?
• Inheritance / super?
• extends?

[rishiosaur]

All of those will be in the lessons to follow :) Lemme add them to the issue

[SleeplessByte]

@rishiosaur how's this going :) ? Need help?

[shubhsk88]

I would like to contribute to this issue or @SleeplessByte maybe you open some new issue related to it

[junedev]

A replacement issue for this one was created to fit the target learning curve: #1015 Please go there if you still want to contribute to the classes concept exercise.
This issue will be closed.