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Hey! You may have been asked this question in an interview or maybe not. Whatever the case is, it doesn’t hurt to always know more. So here I’ll be sharing how to create polyfill for the map, filter, and reduce array methods.

Let’s Code !

Pollyfill for

Let’s first see how

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This article is in continuation with the from the below series :

Again I’ll be sharing 10 questions from real ReactJS interviews for mid level software developer role.

Here we go 🐝 :

Q1: What are higher order components ?

Q2: Explain Error Boundaries.

Q3: How to perform routing in…

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What is Tableau?

Tableau is a visual analytics platform transforming the way we use data to solve problems — empowering people and organizations to make the most of their data. …

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In this article, I’ll be sharing how to add copy to clipboard functionality in your react app without the hassle of installing a library into your app. 😌

So we need to 3 things: ♻️

01: A button : you can take a div or copy icon, anything you would…

Well! Nobody likes a lot of chit-chat before coming to the real thing especially when it comes to the job, so here I’ll be sharing the 10 most common questions that you’ll get in your interview on ReactJS.

I won’t share the answers because it is good to search and…

What is an Array ?

An array is a data structure, which can store a collection of elements of the same data type and has a fixed-size.

We heard it already, right ? Let’s take an example for better understanding.

Consider you have some toy balls of different colours (pink…

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In this tutorial, I am going to explain how to deploy an app on Firebase.
So, if do not have a clear idea on what Firebase is ? I would suggest going through the below link.

Step 01: Create an account on Firebase

Go to

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In this tutorial, I will share how I created a Coronavirus Tracker using react.js and amcharts library.


Before moving on to the tutorial, I expect you have sound knowledge of the three basic pillars of Web Development — HTML, CSS, JAVASCRIPT as well as REACT.JS

In JavaScript, you must have heard of the term Lexical Environment several times.

So what is this Lexical Environment ?

Lexical Environment” is basically a specification object, which stores the association of identifiers to their functions and variables.

Every variable, function, and code block has its own Lexical Environment.


Tanya Singh

Software Engineer | (Java & JavaScript) | Lives in India |

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