Friday, June 11, 2021

Understanding the Magic behind Utility Types in TypeScript

This post will be the conlcuding post in the Introduction to Advanced Types in TypeScript series. It looks at some of the utility Types in TypeScript, explain how it works while pointing out the features within the TypeScript type system that makes it possible.

Why TypeScript?

TypeScript comes with a powerful and expressive type system. Its expressiveness makes it a joy to work with while its powerful features makes it possible to build, and scale large codebases by providing type safety.

One of the ways TypeScript brings about type safety is by providing developers the tool to manipulate types in ways that encode constraints within the type system. This then ensures that code that could lead to runtime exception do not compile, making it possible to catch errors during development time and not in production. One of such tools TypeScript provides for this are Utility Types.

Utility Types are a set of Generic Types that come natively within TypeScript that makes it possible to transform one type into another. This sort of type transformation is useful because it makes it possible to take exiting types, and apply modifications to it which would ensure the enforcement of certain constraints.

In this post, we would look at 2 of such Utility type and how they could be used to provide more type safety. After that, we would take a step back to understand some of the other TypeScript features that come together to make Utility Types possible. Armed with this knowledge, we will then demystify Utility types by taking a peek under the hood of the 2 Utility types in focus to see how they are implemented.

Monday, June 07, 2021

First impressions with Deno from building is a content aggregator for all things TypeScript. It regularly polls RSS feeds for TypeScript related content, which it then list on the site, send out as a tweet via @planetypescript, and also as a weekly digest to subscribers.

Back when I used to write a lot of Java-related content on this blog, I found out that my blog ended up on, which is a site that aggregates Java contents. So when I decided to play around with Deno, I thought a nice little idea would be to build something similar to, but for TypeScript. And that is how was born.

In this post, I will share some of my first impressions with Deno. The things I enjoyed and the bits I found inconvenient. Let's start with the cool stuff.