At work, I have observed different ways of creating functions in the codebase — and that lead me to search for answers on when to use which (declaration versus expression). This articles aims to share why using function expressions is generally preferred over using function declarations.

Macbook opened showing code on IDE

JavaScript has two different…


In my current project, we’re using TypeScript (rather than pure Javascript) for a large-scale application with Node.JS on the server side. …


To handle asynchronous Javascript, callbacks were first used but it had major cons like callback hell. Then came about promises to try to improve things. However, .then chains can also get nested and confusing.
So now, we have async/await, which was introduced in NodeJS 7.6 …


ES6 introduced a number of significant improvements to the language, including de-structuring of Objects and Arrays.

Array Destructuring

Traditionally, to access elements in an Array, you would do so with their index number like so:

const array = [1, 2, 3];console.log(array[0])
// 1

Javascript ES6 allows you to assign the array…


Promises are widely used instead of callbacks. Promises are a great feature in Javascript that enable you to avoid callback hell, especially when you need to wait on a response from multiple API requests that are asynchronous.

A Promise is a special Javascript object that represents the eventual result of…


We will use a simple function called calculateSquare to demonstrate how to handle errors in asynchronous Javascript code.

In order to simulate an asynchronous function, we will use setTimeout:

function calculateSquare(number, callback) {  
setTimeout(() => {
const result = number * number;
callback(result);
}, 1000);
}
let callback = (result)…


If you use Node.js for your applications, you may want to use different versions of Node. Fortunately, there is a tool to manage them all using Node Version Manager.

Node.js


For a work project, I needed to include a wizard form with 2 questions on each page. To get the total page count, I divided the total number of questions by 2 and then rounded it off to the nearest integer. …


Javascript Templating

Javascript templating is a fast and efficient technique to render client-side view templates with Javascript by using a JSON data source. The template is HTML markup, with added templating tags that will either insert variables or run programming logic.

The template engine then replaces variables and instances declared in a…


My work projects rely heavily on the use of Redux Form (paired with React). A problem I struggled with was trying to figure out how to pre-populate my form with initial values. …

Sherlynn Tan

Software Developer at @thoughtworks | Marathon Runner | Ex-Pharmacist Writing on Coding, Technology and Running

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