Back to Blog

TypeScript vs JavaScript

11
Jan
2023
Development
JavaScript vs TypeScript

JavaScript was first introduced as a client-side programming language. Today, it remains one of the most renowned languages worldwide. The community of developers thinks of it as one of the core technologies of modern Web Application Development, and for a good reason! JavaScript is a versatile, fast, potent, and dynamic language. Besides, 97.4% of websites, including Amazon, Google, and Facebook, use JavaScript.

But, like any other language, it has some downsides. For example, larger applications can take much work to maintain using JavaScript. This issue occurs because they didn't create JS to build complex applications. That's the reason why TypeScript, developed and maintained by Microsoft, was created.

TypeScript is a superset of JavaScript that adds additional features. It's an intuitive language that encloses first-class functions like static typing, dynamic typing, modules, Integrated Development Environment (IDE) support, an optional type system, and a class-based object-oriented programming concept. This approach allows you to write more maintainable code for software environments.

This post will examine some core differences between JavaScript and the modern-age language, TypeScript. Further, we'll discuss when it would be a good idea to use TypeScript in your next project. Let's go!

What is TypeScript?

TypeScript is a strong-typed and Object-Oriented programming language. One main advantage is that it provides typed access to JavaScript code. Due to this, you can use TypeScript to write your code and then run it through a compiler to render JavaScript. This feature helps ensure bug-free and reliable code quality or add features unavailable in JS.

This open-source programming language has an intuitive interface, static compilation, and increased code readability, enhancing developer productivity. That's why Microsoft calls it an "improved version of the simple language, JavaScript." TypeScript supports existing code from the scripting language JavaScript. It allows you to add its ecosystem of libraries to improve productivity quickly.

One of the key uses of TypeScript is its ability to help enforce type safety. This trait helps cut potential runtime errors caused by mismatches between variables and values. Imagine you have a variable called "name," and you try to assign it the value "Alice." But you accidentally give it a value of "12" instead.

In standard JS, this would cause no errors at runtime. Yet, with TypeScript, you'd see an error because the variable "name" expects a string value, and "12" does not. You can also see errors when trying to access the value of a property that doesn't exist inside an object.

TypeScript offers an optional static typing feature, which can provide further type safety benefits. Static typing allows you to declare the type of a variable when first defining it. Then, the compiler will check that all references to that variable are of the correct type. This typing avoids issues if code parts use different versions of variables or types.

interfaceUser {
id: number
firstName: string
lastName: string
role: string
}

function updateUser(id, number, update: Partial<user>)
const: user ﹦ getUser(id)
const: newUser ﹦ { ... user, ...update }
saveUser: (id, newUser)
}

Pros and Cons of TypeScript

Pros of TypeScript

● Its static type check helps you prevent runtime issues. Moreover, its readability is vital for early bug detection.
● Optional static typing makes it ideal for large-scale and complex projects. Therefore, it's a good option for building dynamic Web Applications.
● TypeScript types have a complete library set that makes it easy to work with complex data structures.
● Visual Studio Code editor offers features like Predictive Assistance and IntelliSense for TypeScript.
● The new features of this enhanced version of JavaScript include improved API documentation, type annotation, and an additional layer of security, making it a go-to tool for enterprise application development.
● TypeScript code will work on any platform that supports JavaScript.

Cons of TypeScript

●  Finding developers familiar with TypeScript and JavaScript can be challenging. Plus, TypeScript is fairly new and has a stiff learning curve.
● Its additional syntax and rules might be cumbersome and lead to more potential issues in the runtime.
● Code written in TypeScript will not run in browsers that only support JavaScript.
● TypeScript is a newer language. There may be fewer tools available compared with JavaScript.
● Files tend to be larger than their equal JS files due to the extra type of information included.
● Getting up to it can take some time if you're not used to this powerful Object-Oriented language.

Where To Start With TypeScript?

If you want to start with TypeScript, you only need to take a few steps! The first is to install Node.js, as TypeScript is a Node.js program. You can find the installation instructions on the Node.js website.

Once you have Node.js, you can install TypeScript by running the npm install -g typescript command. With TypeScript installed, you're ready to start coding! You can create a new project by running the following declaration: tsc –init. This command will create a new folder called "tsc-init." Inside it, you'll find a file named "tsconfig.json." This step is where you'll configure your project's settings.

The most important setting in this file is the "target" property. These tell TypeScript which version of your JavaScript code to use in compile time. By default, it's "es5", compiling your lines of code into a JavaScript web browser.

You can also specify which modules you want to include in your project. You'll have to add them to the "modules" property. For example, using the React library, you should add "react" to this property. You can configure many other settings in this file. For instance, the type of compiler warnings you want to enable. Also, you can set up whether you wish TypeScript to check for type errors while coding.

Comparing TypeScript vs JavaScript

JavaScript prototype-based language goes back to 1995, while TypeScript appeared in 2012. Yet, there are +2M Stack Overflow questions about "javascript" and approx 205K about "typescript."

JavaScript is a dynamically typed language, while TypeScript is a statically typed language. In JavaScript, you don't need to specify the data type of a variable until using it, while in TypeScript, you do. Static typing can help to catch errors earlier in the development process. Moreover, JavaScript is more flexible, with more advanced features, and is more forgiving. This component can make it easier to learn for beginners. However, it can also lead to more errors and make code harder to read and maintain.

In contrast, TypeScript supports modules and Object-Oriented Programming (OOP). Also, it has an excellent interface. As mentioned earlier, TypeScript offers some advantages over JavaScript. It has stricter rules, which can help to avoid errors. It also provides built-in types that make robust code more concise and readable.

When to use TypeScript instead of JavaScript?

There are a few cases where you might want to use TypeScript's prominent features instead of JavaScript:

1. Large-Scale Applications. TypeScript often focuses on large-level complex applications with a more structured codebase. It can help prevent errors and make code maintainability easier.

2. Focus on Speed. If you need reusable modules and speed is a priority, TypeScript can be a great option. Its error warnings feature will prevent teams from spending hours debugging code.

3. Static Typing. Some projects might need strong typing. Often, this procedure ensures performance without having to run too many tests. If a project is prone to need refactoring, it will be much easier to do due to the static typing of TypeScript.

It might seem that TypeScript is more helpful for any project. However, in some cases, you should stick to JavaScript. For example, if you're working on small-scale applications requiring only a small structure. If your codebase doesn't need a wide range of updates from many developers, Typescript may not be the best choice for developers. If your team is more comfortable with JavaScript, TypeScript may be optional. In fact, it might be counterintuitive to push a different language.

Conclusion

TypeScript and JavaScript are both popular programming languages for Front and Back-End Development. Even though there are a few key differences, they are almost identical. TypeScript offers static typing, object-oriented programming, and warning of errors at compilation time. JavaScript developers think it is less strict than TypeScript, making it a preferred choice for simple Web Applications. Both can provide magnificent key features for Cross-Platform and Web Development! But, it would be best to acknowledge your development project requirements before choosing.