IT-блоги • Typealias vs Interface in TypeScript: Which to use in 2024.

TypeScript is JavaScript and more, it is a subset of JavaScript that allows you to define the data types used within the code.

There are two ways of defining types in TypeScript: type aliases and interfaces. Based on performance, there is no difference between the two, but questions on whether to use type aliases or interfaces often arise.

To answer this question, it often depends on personal preferences, as none of them affect performance, although based on simplicity and clarity, we could prefer one over the other.

In this blog post, I will discuss the advantages type aliases have over interfaces and use cases.

Using type aliases and interfaces.

Type aliases

Type aliases can be used to define primitives like strings or more complex types like objects and arrays.

Interfaces

Interfaces are similar to type aliases, except they are used to define object types.

Reasons why you should use type alias instead of interface all through your projects:

Simplicity.

• Interface can only describe objects, whereas a type alias can describe objects and everything.

• Type aliases can describe union types, while interfaces cannot.

• Extracting types from something else.

Clarity and improved readability.

• Type aliases can easily use utility types; interfaces can too, but only with ugly syntax.

• Type aliases can easily describe tuples; interfaces can, but with ugly syntax.

Conclusion

In this article, we've discussed type aliases and interfaces, and the advantages type aliases have over interfaces.
We've discussed up to six scenarios where type alias is preferred over interface, but it still depends on one's preference.
I like using types because of its incredible type system. So why not use it throughout your code?