13 cutting-edge JavaScript features that will accelerate your development
JavaScript best practices!
Among all the programming languages, JavaScript is by far the most popular. It is a lightweight programming language with first-class functions. You can advance your career in web development by mastering it. Additionally, learning its best practices will advance your career. In this brief story, you’ll learn about some incredibly helpful JavaScript features that will enhance your ability as a JavaScript programmer.
So let’s get started!
1. Use strict mode
To impose strict coding standards and identify any issues early, useuse strictkeywords at the beginning of your JavaScript code. Using it allows you to avoid undeclared variables, which improves code quality.
"use strict";
x = 5; // this will cause an error in strict mode
2. Use ‘let’ and `const`
When declaring variables, useletandconst instead of var. Use let ifyou know the value of a variable and const if you don’t.
let greetings = "Hello World!";
const pi = 3.14;
3. Use `===` instead of `==`
Double equal converts type and checks for only value equality. However, triple equal does not convert type but checks both type and value. In the example below, the (===) operator returns false since x and y are of different types.
Generally, if you use (===) with different types of values, you won’t get unexpected results. Using (===) is recommended.
const x = 10;
const y = "10";
// Using == operator (type coercion allowed)
console.log(x == y); // true
// Using === operator (type coercion not allowed)
console.log(x === y); // false
4. Write modular code
It will be simpler to test and maintain your code if you divide it into manageable, and reusable functions.
function add(a, b) {
return a + b;
}
function subtract(a, b) {
return a - b;
}
console.log(add(1, 2)); // 3console.log(subtract(1, 2)); // -1
5. Built-in functions
Use the features that are already there. There are numerous built-in JavaScript functions, such as Math.floor() and Array.sort(), which can simplify and enhance your code.
let number = Math.floor(3.14);
console.log(number); // 3
let numbers = [1, 2, 3, 4, 5];
numbers.sort((a, b) => a - b);
console.log(numbers); // [1, 2, 3, 4, 5]
6. Use arrow functions
Arrow functions were added to JavaScript in ES6. Use the arrow functions, ‘() =>’, for comprehensible and readable JavaScript functions.
const add = (a, b) => a + b;
const subtract = (a, b) => a - b;
console.log(add(1, 2)); // 3
console.log(subtract(1, 2)); // -1
7. Template literals
Template literals are enclosed in backtick (`` ) characters rather than double or single quotes. Through the use of template literals, variables and expressions can be easily interpolated into strings***.*** The method is called “string interpolation.”
let name = "John Doe";
console.log(`Hello ${name}!`); // Hello John Doe!
8. Object destructuring
Object destructuring is a technique for removing values from objects and optimizing your code. Using the JavaScript Object Destructuring expression, you can access the information contained in objects such as arrays, objects, and maps and assign it to new variables. This object destructuring allows for the quick creation of variables from the object’s properties.
let person = { name: "John Doe", age: 30 };
let { name, age } = person;
console.log(name, age); // John Doe 30
9. Global variables
Variables declared outside of the function have global scope. In a JavaScript program, you can access global variables from anywhere. Handle global variables with care and use them wisely in JavaScript, as they can cause naming collisions and are considered poor coding practices.
// global variable
var message = "Hello World!";
function showMessage() {
console.log(message); // Hello World!}
10. Use ‘null’ and ‘undefined’ appropriately
Null is a primitive type in JavaScript that represents an empty value. When you set a variable to null, it has no value. Contrarily, undefined means that a variable has been declared but has not yet been assigned a value.
Know the difference between null and undefined, and use them correctly to avoid unexpected results in your code.
let message;
console.log(message === undefined); // true
message = null;
console.log(message === null); // true
11. Use promises
Promises are a powerful tool for handling asynchronous operations in JavaScript. Having a solid understanding of promises will help you write code more effectively.
let promise = new Promise((resolve, reject) => {
setTimeout(() => resolve("Hello World!"), 1000);
});
promise.then(message => console.log(message)); // Hello World!
12. Use modern JavaScript features
For more effective and elegant code, use modern JavaScript features like async/await. The W3Schools states, “async and await make promises easier to write."
async function getData() {
let response = await fetch("https://api.example.com");
let data = await response.json();return data;
}
getData().then(data => console.log(data));
13. JavaScript libraries and frameworks
Using JavaScript libraries and frameworks like jQuery and React to organize and clean up your code will save you time and effort.
// jQuery
$("button").click(event => {
console.log("Clicked!");
});
// React
function Button({ onClick }) {
return <button onClick={onClick}>Click me!</button>;
}
ReactDOM.render(
<Button onClick={() => console.log("Clicked!")} />,
document.getElementById("root")
);
Conclusion
That’s it for today! I really hope you find it useful; if so, be sure to clap and share it with others. Ask me anything on Twitter if you have any queries.
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Happy learning!