Set was introduced in ES6 and is a collection of values without keys. It has one killer feature that you want to use - filtering duplicates owing to its feature of allowing only unique values. So.. set? People from other languages may be familiar with sets, maps and arrays.. and the confusion that comes with them.

There are many great improvements provided by ES6 (introduced in Y2015), but I think a couple of them are really cool. String includes includes checks whether a certain (sub) string exists in the provided string. Note that this operation is case sensitive. 1 2 3 let str1 = "Neo rocks the world"; console.

We define a class and its variables like so - 1 2 3 4 5 6 7 8 9 10 11 12 class UserData { name = ""; type = ""; internalUserFlag = false; constructor({ name, type }) { this.name = name; this.type = type; } } const student1 = new UserData({ name: "Neo" }); console.

Extend a class and create a sub class for easier maintainability. Sub class can make use of special super functions to extend the functionality of a class. Using sub classes you can build out a complex logic in steps rather than as one messy module. See how to start with a Javascript class and class prototypes if you are new to Javascript classes.

Prototypes enable us to define attributes and functions of a class that can be shared across its object instances. Let us look at how we could start using prototypes in our Javascript classes. See how to start with a Javascript class if you are new to Javascript classes. Class in Javascript is built internally using prototypes - in fact that was the way some of us were reaching OOP nirvana in Javascript back in the day.

Class in Javascript is syntactic sugar on top of prototypes. Class makes it easier to structure our code, and to read and maintain it. Let’s see a simple class. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 class QuizTracker { constructor() { this.

Arrays in Javascript can be sorted using a simple .sort command. But, don’t let that simplicity deceive you - it goes far more than that. 1 2 let arr = [4, 2, 1, 7, 3]; console.log(arr.sort()); // [ 1, 2, 3, 4, 7 ] Sort can be used against full strings -

Array is a collection of elements or objects, and is quite easy to use in Javascript. Here’s an example of array: 1 const fruits = ["apple", "orange"]; You can print out the entire array.. 1 2 const fruits = ["apple", "orange"]; console.log("fruits: ", fruits); //fruits: [ 'apple', 'orange' ] .

You can pass one or more values to a function, but that has been made much easier and streamlined with the advent of ES2015 - 2018 standards. Let’s start with a simple function. 1 2 3 4 5 6 function sum(x, y) { return x + y; } const summer = sum(3, 6); console.

A Javascript function returns one and only one value. 1 2 3 4 5 6 function sum(x, y) { return 3 + 39; } let life = sum(3, 39); console.log(life); // 42 I bet you already knew that not returning a value from a function, would return ‘undefined’.

AND (&&), Not (!), OR (||) are logical operators in Javascript. You will see that they are the only operators that make up for the entirety of one’s life experiences. Logical operators evaluate two values or expressions, and provide a true or false result. Let us see some examples to know the rules of the game.

Equals (==), not equals (!=), greater than (>), lesser than (<) - Javascript comparison operators cannot get more simple. Let’s dissect these operators a bit. Comparison operators are the ones that you use to.. well, compare. For example: 1 2 3 4 5 6 7 let numCoffee = 3; if (numCoffee < 2) console.

Know how you can use a Javascript object and its props. Javascript objects have properties or props. As you would have seen in the post about objects and primitives, object operations are quite easy. Though objects can mean more than a few things in Javascript, we will limit discussion of an object to the ** real real ** object.