Introduction:
TypeScript, built upon the foundation of ES6 and beyond, marries the power of modern JavaScript with the benefits of a static type system. This duo enables developers to write clean, expressive, and error-free code. Whether you're a seasoned pro or new to TypeScript, adopting best practices will help you harness the full potential of this dynamic blend. 🎉
In this guide, we'll delve into best practices for TypeScript, exploring how to seamlessly integrate ES6 and its successors to write elegant and maintainable code.
✅ Utilize ES6 Features for TypeScript Advancements 🛠️
TypeScript embraces ES6 features and more. Leverage these features to make your code more concise and maintainable:
// Good
const calculateTotal = (price, quantity) => price * quantity;
❌ Avoid: Using outdated function syntax without utilizing the power of arrow functions:
// Bad
function calculateTotal(price, quantity) {
return price * quantity;
}
✅ Embrace ES6 Modules for Organized Code 📦
ES6 module syntax improves code organization, encapsulation, and clarity:
// Good
import { User } from './models/user';
import { calculateTotal } from './utils/math';
❌ Avoid: Mixing old-style module patterns without reaping the benefits of modern import/export:
// Bad
const User = require('./models/user');
✅ Explicit Types, ES6 Syntax 📜
Combine explicit TypeScript types with ES6 syntax for enhanced readability and type safety:
// Good
const greetUser = (name: string) => `Hello, ${name}!`;
❌ Avoid: Using vague or untyped parameters with ES5 syntax:
// Bad
function greetUser(name) {
return 'Hello, ' + name + '!';
}
✅ Use ES6 Set and Map for Complex Data Structures 🗺️
Leverage ES6 Set and Map with TypeScript's type safety for managing complex data:
// Good
const uniqueIds = new Set<number>();
const userMap = new Map<number, User>();
❌ Avoid: Using arrays or objects for the same purpose, missing out on the benefits of specialized data structures:
// Bad
const uniqueIds = [];
const userMap = {};
✅ Promises and Async/Await: ES6 Elegance with TypeScript Types ⏱️
Take advantage of TypeScript's type inference combined with ES6 Promises and async/await for asynchronous operations:
// Good
const fetchData = async(): Promise<Data> => {
const response = await fetch('https://api.example.com/data');
const data = await response.json();
return data;
}
❌ Avoid: Using callback-based asynchronous patterns, which are less readable and error-prone:
// Bad
function fetchData(callback) {
fetch('https://api.example.com/data')
.then(response => response.json())
.then(data => callback(data))
.catch(error => console.error(error));
}
✅ Leverage Default Parameters for Function Flexibility 🔄
Utilize ES6 default parameters to provide fallback values and enhance the flexibility of your functions:
// Good
const greetUser = (name = 'Guest') => {
return `Hello, ${name}!`;
}
❌ Avoid: Manually checking and assigning default values within your function body:
// Bad
const greetUser = (name) => {
if (!name) {
name = 'Guest';
}
return 'Hello, ' + name + '!';
}
✅ Simplify Object Creation with Object Shorthand and Destructuring 🏗️
Use object shorthand and destructuring for cleaner and more concise object property assignments:
// Good
const name = 'Alice';
const age = 30;
const user = { name, age };
❌ Avoid: Verbose and repetitive property assignments using traditional syntax:
// Bad
const user = { name: name, age: age };
Conclusion:
Combining TypeScript with ES6 features empowers developers to write more expressive, maintainable, and error-resistant code. By adhering to these best practices, you'll create a codebase that's robust, efficient, and easier to work with. The synergy between TypeScript and ES6 is where the true magic happens, enabling us to create software that's not just functional, but elegant too.
So, as you embark on your TypeScript journey, remember that embracing the best of both worlds unlocks limitless possibilities. Happy coding! 👨💻👩💻
Top comments (11)
Great article!
I would include "stop using the I prefix at interfaces", which is a very common pattern for TS developers. I don't know how that C# convention invaded TypeScript world. (Microsoft behind both of them probably is a coincidence since they discourage it)
Some developers make the case that not using it cause weird code like
class Dog implements Dog, but that actually shows issues with the code design (in this case, is the Dog class really necessary? If it is, than the interface Dog probably isn't).You're right that the "I" prefix convention has been a common pattern in the TypeScript world, and it's valuable to discuss its implications. I agree that avoiding it can lead to cleaner code and better alignment with TypeScript's idioms. Your example of the class Dog implementing Dog is a thought-provoking one that highlights potential code design issues.
You've given me an idea for an insightful follow-up discussion on this topic. Thank you for sharing your perspective!
Outdated function syntax? 🤨
That is what you must avoid.
Named function is not outdated at all. developer.mozilla.org/en-US/docs/W...
Alas, the function keyword is the base in all programming languages.
Using anonymous functions is a personal preference and you lose hoisting and can be harder to debug.
Thank you for taking the time to share your thoughts. You're absolutely right that the choice between arrow functions and traditional named functions is indeed a matter of preference and context. Arrow functions offer concise syntax and lexical scoping, while traditional named functions provide hoisting and possibly clearer stack traces. Both have their merits, and it's wonderful that developers have the flexibility to choose the style that best suits their needs and the project's requirements.
I think a better advise would be to not mix them in the same project/module. Sometimes I see code that has both types of declaration used in similar ways and in the same scope, probably because of different developers acting on the project. It makes the code look ugly and a bit confusing.
If you're going to use traditional named funtions, stick to it, maybe with the exception of callbacks.
Functions and Arrow Function serve their own purpose. They are not contradicting each other. Example this binding
@brunomonteiro1 @emil
I strongly agree
Amazing, good cheat sheet, thanks!
thanks