JavaScript Latest Best Practices 

Spread the love

JavaScript is the most flexible language which allows you to try unusual things in the code, which leads to bug. Here are few JavaScript  best practices which you should know before you write code.

  1. Stop using “var” and Consider Using “let” and “const”…

Declarations with “var” are also hoisted which makes var declarations accessible before where the declarations happened, which is non-obvious behaviour.

The “let” keyword allows us to create local variables that are scoped within their own block. The “const” keyword allows us to create local block-scoped variables whose value cannot be reassigned.


So, use the “let” and “const” keywords in appropriate situations while declaring your variables.


  1. Organize your declarations

Be consistent with the way you declare things. Put all your declarations on top starting with the constants down to the variables. Make constants all uppercase to indicate they are constants which will prevent devs from trying to change them.


  1. Comment Your Code

Add comments when you did something not common or require context to be understood. Also, add comments to things that are a hack or may require improvements/fixing later on so the next person knows why. Add comments in your third parties’ modules and modules in your codebase to explain the architecture and the intention behind things.


  1. Use === Instead of ==

JavaScript has two kinds of equality operators

  • strict operators ( ==== and !== )
  • non-strict operators ( == and != )

While using non-strict operator, you will get an issue when you have different data types. So, it is always best practice

To use strict operator.


  1. Use “destructuring”

Destructuring makes it more obvious what you need from arrays and objects. It also gives you the opportunity to rename things which gives more sense to your code.


  1. Use the Spread Operator

Have you ever been in a situation where you wanted to pass all the items of an array as individual elements to some other function or you wanted to insert all the values from one array into another? The spread operator (…) allows us to do exactly that.


  1. Prefer promises over callbacks

Promises are easy to use and anything with a callback can be “promisified”. Callbacks are the functions to call once something is done whether synchronous or not and with promises and async…await you get to do things asynchronous which may speed up your code, especially because JavaScript is single-threaded. You can’t get away with promises only sometimes but promises make it easy to read code as well.


  1. async and await

You can use the async keyword to create asynchronous functions, which always return a promise either explicitly or implicitly. Asynchronous functions that you create can take advantage of the await keyword by stopping execution until the resolution of returned promises. The code outside your async function will keep executing normally.


  1. Use Arrow Functions

Another essential feature added to JavaScript recently is arrow functions. They come with a slew of benefits. To begin with, they make the functional elements of JavaScript more appealing to the eye and easier to write.

Another notable benefit of arrow functions is that they do not define a scope, instead being within the parent scope. This prevents many of the issues that can occur when using the this keyword. There are no bindings for this in the arrow functions. this has the same value inside the arrow function as it does in the parent scope. However, this means arrow functions can’t be used as constructors or methods.


  1. For loops > .forEach sometimes

Don’t change things into an array just so you can “.forEach” it. You are adding an extra process to a slow alternative. Loops are faster and allow you to use the “continue” and “break” keywords to control the looping.


  1. Avoid nesting or chaining loops

When you chain iteration method or nest loops you are increasing the complexity of the code which may slow things down later on or as your data grows. Even though some operations may require it, always assess your looping strategy to ensure you don’t have unnecessary loops or loops that can be combined together.


  1. Always “try…catch” JSON methods

Don’t trust things passed to JSON methods “.stringify” and “.parse”. Try to catch them to make sure they don’t fail and break your code.

Add semicolons, always!

You may be surprised to find out that you can get away with not putting a semicolon in the JavaScript code. Know that the compiler adds them and tools like Babel may easily misread your code and cause a bug to make to production. Always add semicolons!

  1. Raw JavaScript Is Always Quicker Than Using a Library

JavaScript libraries, such as jQuery and lodash, can save you an enormous amount of time when coding—especially with AJAX operations. Having said that, always keep in mind that a library can never be as fast as raw JavaScript (assuming you code correctly).

jQuery’s each() method is great for looping, but using a native for statement will always be an ounce quicker.

  1. Put JavaScript in a Separate File

JavaScript can be written in a <script> tag in your HTML, or it can be kept in its own file and linked within your HTML. This helps keep different sorts of code isolated from one another this manner, and makes your code more understandable and well-organized.

Keeping your JavaScript in separate files outside of the HTML facilitates the reuse of code across multiple HTML files. It provides for easier code reading, and it saves loading time since web browsers can cache external JavaScript files.



Leave a Reply

Your email address will not be published. Required fields are marked *