50 JavaScript Tips to help you learn faster and write better code

JavaScript has solidified its position as one of the core technologies of the web. Whether you’re a novice looking to grasp the basics or an intermediate coder aiming to level up, there’s always room for improvement. Refining your JavaScript skills not only helps in building sophisticated web applications but also plays a vital role in code maintainability, performance, and readability. This article is a treasure trove of tips to help you grasp the essentials faster and write more elegant and efficient code.

Learning Fundamentals Faster

Before you can harness the full power of JavaScript and its myriad of libraries and frameworks, understanding its core is vital. Let’s explore how to accelerate this foundational learning.

Start with basics

The foundational blocks of JavaScript are variables, data types, and operators.

Variables are used to store data values. In JavaScript, let, const, and var (less recommended nowadays) are used for variable declarations.
let name = 'codedamn';
Data types in JavaScript include primitives like String, Number, Boolean, null, undefined, and Symbol, and reference types such as Object.
Operators perform operations on variables and values. Examples include arithmetic operators (+, -, *, /), comparison operators (==, ===, !=, !==), and logical operators (&&, ||, !).

The key is not to rush. Master these basics, as they serve as the pillars for advanced topics.

Use interactive platforms

Platforms like codedamn are incredible tools for real-time JavaScript coding. They provide a javascript playground to test snippets, experiment with ideas, and see immediate results without setting up a full-blown development environment.

Dive into MDN Web Docs

The Mozilla Developer Network (MDN) Web Docs is a gold standard for JavaScript documentation. It offers in-depth articles, tutorials, and references. Whenever in doubt about a JavaScript function, method, or property, MDN should be your first stop.

Understand the DOM

The Document Object Model (DOM) is a programming interface for web documents. It represents the structure of a document as a tree of objects. Each object corresponds to a part of the document, like elements or attributes. Grasping the DOM is fundamental because it allows JavaScript to read or change the document content, structure, and style.

Practice regularly

The saying “practice makes perfect” holds in programming. Codedamn provides coding challenges that can significantly improve your problem-solving skills and JavaScript proficiency.

Clean Code Principles

Readable and maintainable code isn’t a luxury; it’s a necessity. Here are some principles to ensure your JavaScript remains pristine.

Use meaningful variable names

Instead of ambiguous names like x or temp, use descriptive names like username or initialTemperature. It makes the code self-explanatory and improves maintainability.

Stick to the DRY principle

“Don’t Repeat Yourself” is about reducing redundancy. If you find yourself writing the same code in multiple places, it might be time to create a function or module to encapsulate that logic.

Comment your code

Comments should explain the “why” and not the “what”. While it’s essential to avoid over-commenting, judicious use of comments can elucidate complex logic or remind you of pending tasks (// TODO: add error handling).

Keep functions short

A function should do one thing and do it well. Following the single responsibility principle makes functions easier to read, test, and debug.

Follow a consistent code style

Whether it’s spaces vs. tabs, single vs. double quotes, or how to structure your curly braces, sticking to a style makes your code predictable. Tools like ESLint combined with style guides like Airbnb’s JavaScript Style Guide can automate this process.

ES6 and Beyond

JavaScript has evolved significantly with the ES6 update and subsequent versions. Here’s a look at some standout features.

Arrow Functions

Introduced in ES6, arrow functions provide a concise way to write functions.

const greet = name => `Hello, ${name}!`;

Promises and async/await

Promises represent a value which might be available now, or in the future, or never. async/await makes asynchronous code look and behave like synchronous code, improving readability.

async function fetchData() {

let response = await fetch('https://api.codedamn.com/data');

let data = await response.json();

return data;

}

Template literals

Using backticks (“), template literals allow embedded expressions and multi-line strings.

let platform = 'codedamn';

let message = `Welcome to ${platform}!`;

Spread/rest operators

The spread operator (...) allows an iterable to expand in places where arguments or elements are expected. The rest parameter syntax allows representing an indefinite number of arguments as an array.

let arr1 = [1, 2, 3];

let arr2 = [...arr1, 4, 5]; // Spread

function displayNumbers(…nums) { // Rest
console.log(nums);
}

Destructuring

Destructuring allows binding properties of an array or object to variables.

let user = { name: 'Mehul', platform: 'codedamn' };

let { name, platform } = user;

console.log(name, platform); // Outputs: Mehul codedamn

Embracing these features and practices can propel your JavaScript journey, making you a more efficient and effective coder. Happy coding on codedamn!

Performance Tips

Strategies for writing efficient and optimized JavaScript.

Use const and let

In modern JavaScript, it’s considered best practice to use const and let over the traditional var for variable declarations. Both const and let provide block-level scoping, unlike var, which is function-scoped.

const: Use this when the variable’s value will not change. It creates a constant reference to a value.
let: This is used when the variable’s value will change over time.

Benefits:

Better readability and predictability.
Reduced risk of unintentional global variables due to block-level scope.
Helps in avoiding bugs by making sure that values that shouldn’t change remain constant.

== vs. ===

JavaScript provides two types of equality checks: loose equality (==) and strict equality (===).

==: Compares values for equality after performing type coercion if needed. For instance, "5" == 5 will return true.
===: Checks values for equality without type coercion. Hence, "5" === 5 returns false.

For more consistent and predictable code, prefer using === to avoid unintended type conversions.

Browser developer tools

Modern browsers come equipped with developer tools that can be invaluable for JavaScript developers. Here are some ways to leverage them:

Debugger: Set breakpoints, inspect variables, and navigate the call stack.
Profiler: Assess runtime performance and find bottlenecks.
Console: Execute JS code in real-time and view logs.
Network: Monitor network requests and responses.

For an in-depth guide, check out Chrome DevTools official documentation.

Limit global scope

Global variables can potentially clash with other scripts and libraries. It’s a good practice to encapsulate your code within functions or modules to avoid unintentional global scope pollution.

Techniques:

Use Immediately Invoked Function Expressions (IIFE).
Utilize ES6 modules.

Memory leaks

Memory leaks can degrade your application’s performance over time. In JavaScript, they can arise from:

Unintentionally holding onto references.
Forgotten timers or callbacks.
DOM references after elements are removed.

To identify and prevent them:

Use browser profiling tools to monitor memory usage.
Regularly review and clean up callbacks, listeners, and global variables.

Working with Arrays and Objects

Deep dive into two of the fundamental constructs in JavaScript.

Array methods

JavaScript arrays come with powerful built-in methods:

map(): Create a new array by transforming every element of the original array.
filter(): Construct a new array containing only those elements that satisfy a certain condition.
reduce(): Reduce an array to a single value based on some accumulator function.

For a comprehensive list, visit the MDN Web Docs on Array.

Deep vs. shallow copy

When copying arrays or objects, understand whether you need a shallow or a deep copy:

Shallow copy: Only the top-level elements are copied, not nested ones. Modifying nested elements will affect the original.
Deep copy: All levels are recursively copied. Original remains unaffected by changes to the copy.

Use spread (...) or Object.assign() for shallow copying. For deep copying, methods like JSON.parse(JSON.stringify(obj)) can be used, but remember, this won’t handle functions or special objects.

Object prototypes

In JavaScript, inheritance is prototypal. Every object can have a prototype from which it inherits properties. It’s crucial to understand this chain and how properties are looked up.

JSON methods

JSON.stringify() and JSON.parse() are commonly used methods for working with JSON data in JavaScript:

JSON.stringify(): Convert a JavaScript object or value to a JSON string.
JSON.parse(): Convert a JSON string into a corresponding JavaScript object or value.

These methods are essential when communicating with APIs and storing structured data.

Object destructuring

Destructuring allows you to unpack properties from objects or elements from arrays. It provides a cleaner syntax and can be especially handy when working with function arguments or React components.

Example:

const person = { name: 'John', age: 30 };

const { name, age } = person;

Handling Events and Async Programming

Mastering asynchronous operations and event handling.

Event loop and callback queue

The JavaScript event loop is the heart of its single-threaded, non-blocking I/O model. Here’s a basic rundown:

Execute script: Run script code.
Event loop: Continually checks if there are messages (callbacks) in the queue. If there’s a message and the stack is empty, the message is dequeued and executed.

For a visual and in-depth guide, explore Loupe, an interactive tool by Philip Roberts.

Event delegation

Instead of adding event listeners to individual elements, add a single listener to a parent element. This leverages event bubbling in the DOM and can optimize performance for dynamic elements.

Benefits:

Less overhead by reducing the number of event listeners.
Automatically handles dynamically added child elements.

Error handling with try/catch

Errors are inevitable in coding. Use the try/catch statement to gracefully handle them:

try {

// code that might throw an error

} catch (error) {

// handle the error

}

Throttling vs. Debouncing

These techniques optimize the number of times certain code runs:

Throttling: Ensures a function only executes once in a specified time frame.
Debouncing: Delays the execution of a function until after a specified wait time since the last time the function was invoked.

For instance, they can be used to optimize scroll or resize event listeners.

Promise.all()

Use Promise.all() to wait for multiple promises to resolve:

Promise.all([promise1, promise2]).then((values) => {

console.log(values);

});

Functional Programming in JavaScript

Introduction to the functional paradigm in JS.

Ramda and Lodash

Ramda and Lodash are two popular JavaScript libraries that facilitate functional programming, providing utility functions for working with arrays, objects, and other data structures. Explore their official documentation (Ramda, Lodash) to get started.

Tips for Better Debugging

Strategies to efficiently find and fix bugs in JS.

“strict mode”

Activate strict mode in JavaScript using 'use strict'; at the beginning of a script or function. It helps catch common programming bugs by:

Preventing the use of implicitly declared variables.
Making assignments that would otherwise silently fail to throw an error.
And other safety measures.

Tools and Extensions

Boost productivity and maintain code quality with the right tools.

Webpack or Parcel

Both Webpack and Parcel are module bundlers and task runners. They process and bundle your JS, CSS, and other assets into optimized packages ready for deployment.

Webpack: Highly configurable and widely used in the industry. Check the official documentation.

Parcel: Touts itself as a zero-configuration bundler, offering faster builds out of the box. Visit the official site for more.

Conclusion

The journey of mastering JavaScript is continuous, shaped by regular practice, community engagement, and real-world challenges. At codedamn, we encourage constant learning and hope these tips will guide you towards writing better, efficient, and bug-free code.

Further Resources

Continue your JavaScript exploration:

MDN Web Docs – Comprehensive resource on JavaScript.
JavaScript.info – Deep dive into the nuances of the language.
ES6 Features – Get familiar with the modern features of JavaScript.

Stay curious and happy coding!