For a web developer, choosing the right programming language or tool for a specific project is paramount. The lately going-on increase in TypeScript's popularity has now pitted it head-to-head with JavaScript, and there are many valid reasons for this. In this blog, I will show you why you might choose to use TypeScript instead of JavaScript, with the help of some examples that expose its advantages.
Type Safety
Type safety is just one reason why you might want to consider TypeScript. The types of variables, function parameters, and return values can all be defined when JavaScript fails in this regard. This helps to catch errors during compile time rather than run time.
//JavaScript
function add(a, b) {
return a + b;
}
add(10, '20'); // This will return '1020', Not 30
/* TypeScript */
function add(a:number, b:number):number {
return a + b;
}
add(10, 20); // This will return 30
// add(10, '20'); // This will give a compile time error
Improved IDE Integration
TypeScript provides better tooling and IDE support than JavaScript. Modern IDEs, e.g., Visual Studio Code, come with features like IntelliSense, providing intelligent code completion, parameter info, and more.
// With TypeScript
interface User {
id: number;
name: string;
email: string;
}
const getUser = (userId: number): User => {
// get user logic
return { id: userId, name: 'John Doe', email: 'john.doe@example.com' };
}
const user = getUser(1);
console.log(user.email); // IntelliSense helps here
Better Refactoring
With TypeScript, refactoring is simplified and safer. For example, if you change a type or an interface, TypeScript notifies you where something broke in your code because of these changes. Large-scale refactoring thus becomes quite manageable when using TypeScript.
//TypeScript
interface User {
id: number;
fullName: string; // Changed from 'name' to 'fullName'
email: string;
}
const getUser = (userId: number): User => {
return { id: userId, fullName: 'John Doe', email: 'john.doe@example.com' };
}
const user = getUser(1);
console.log(user.fullName); // TypeScript will flag any issues with this change
Conclusion
While JavaScript is a great and highly flexible language, there are certain advantages in TypeScript that help bring much stronger and maintainable logic into the codebase. These major features give great value to modern web development because of its type safety, better IDE support, and refactoring capabilities. In your next project, consider using TypeScript if you haven't already tried it.
Top comments (11)
I agree that Better Refactoring is true for interface redefinition, that's a very good point.
I find that I don't really agree with "Improved IDE Integration" - I get highly accurate IntelliSense using JSDoc and the smarts of WebStorm, I never have to remember anything these days :)
Thanks for your input! You’re right—JSDoc with WebStorm offers great IntelliSense. TypeScript’s advantage, in my view, is in adding compile-time type checking, which can catch errors earlier. But it definitely depends on personal preference and project needs. Appreciate your perspective!
I don't think this is true? JSDoc is powerful but as I understand nowhere near as powerful as Typescript. It barely supports the idea of abstract classes from what I could tell when I tried it a few weeks ago and declaring re-usable types for objects in the way we make interfaces in TS was a pain at best. Those things give you better IDE integration as they tell your IDE better how things are supposed to work. Plus if you're already writing all that boiler plate, why not use TS anyways since its more powerful? The only issue I find with it is that compiling for frontend is still a pain in the ass and the fact that it doesn't work without build tools well or if it does there is a serious lack of easy to find documentation for it. Even then though, if you're doing most modern frontend web dev, you probably have a frontend build pipeline anyways so it seems like a moot point to point at that as the barrier too.
Abstract classes are just a construct used to structure something. I don't use them; I use interfaces because they are more handy. Interfaces work fine in JSDoc. I don't know about abstract classes.
Abstract classes and interfaces should be very different. A good class heirarchy should have both interfaces and abstract classes mixed. There are things that abstract classes denote and functionalities that they provide that can not be leveraged by an interface unless they are using the word interface as a misnomer.
Thanks for your detailed response, Sophie! You’re right—TypeScript does offer more powerful features like abstract classes and interfaces, which definitely enhance IDE support. I also get what you’re saying about the build process; it can be a bit of a pain. But as you mentioned, with most modern projects having a build pipeline, adding TypeScript might not be as tough. Appreciate you sharing your thoughts!
Typescript is more likely a IDE extension, and when used with React the code really becomes messy. And doesn’t provide a great developer experience.
I wish there was a more better way to write React with Typescript.
I wrote a two React state handling npm module. One of them is typescript:
react-state-factory
and the next one is jsDoc state handling without react-saga support. So that is much more lightweight.
jsdoc-duck
Each of these library just for one prupose: give state and actions type and get a useReducer result with typesafe actions.
Of course does not use this lib any one. ( expect me ) But lets take a look that is give a real lightweight midcomplex state handling for react and each code under 100 LOC.
Thanks for your input! I get what you mean—TypeScript can feel cumbersome with React. It’s all about balancing structure and simplicity. Hopefully, future tools will make this smoother. Appreciate your perspective!
Curious question:
What about typescript+ react is cumbersome ?
I find it to be a better interface than before with using react proptypes. It's much more expressive and also shareable.
You can write component types and extend them for higher level components.
Another note is that typescript propagates types from lower level to upper level..
Once used correctly the types propagate and get out of your way..it just provides intelligence for the consumers.
I also see a lot of code where types are imported when they are not needed.. retyping things when typescript can provide inferences.
This can indeed be cumbersome but taking advantage of inferring types can reduce this pain
Thanks for the thoughtful question! I agree—when used well, TypeScript can really enhance the React experience. It offers a more expressive, shareable interface compared to PropTypes, and the way it propagates types up the component tree is powerful.
I think the "cumbersome" feeling often comes from over-typing or not fully leveraging TypeScript’s type inference, which can lead to unnecessary complexity. But once you get the hang of it and let TypeScript do its thing, it really does streamline development and boosts productivity.
Appreciate your insights on this!