2024-01-15
1954
#typescript
Oyinkansola Awosan
96803
Jan 15, 2024 ⋅ 6 min read

How to use type guards in TypeScript

Oyinkansola Awosan I'm a fun techie and passionate technical writer interested in data science, machine learning, cloud engineering, and blockchain technologies.

Recent posts:

Zoneless Change Detection In Angular 18

Zoneless change detection in Angular 18

Angular v18 introduced an experimental feature called zoneless change detection, eliminating the need for Zone.js.

Yan Sun
Jul 15, 2024 ⋅ 5 min read
Developing Cross Platform Apps With Bun Version 1.1

Developing cross-platform apps with Bun v1.1

For some years now, developers have faced many performance challenges while using traditional JavaScript runtimes like Node.js and Deno. Even […]

Clara Ekekenta
Jul 12, 2024 ⋅ 6 min read
Exploring The Magic Of Runes In Svelte 5

Exploring the magic of runes in Svelte 5

See how to use Svelte 5’s new runes system to declare reactive states and compare them to the existing approach to reactivity in Svelte 4.

Yashodhan Joshi
Jul 11, 2024 ⋅ 7 min read
Building UIs With Franken UI, A Shadcn Alternative

Building UIs with Franken UI, a Shadcn alternative

Explore Franken UI, an open source library of pre-built UI components that takes inspiration from Shadcn UI’s design principles.

Jude Miracle
Jul 10, 2024 ⋅ 11 min read
View all posts

6 Replies to "How to use type guards in TypeScript"

  1. The section on the typeof operator is somewhat incorrect. I can be string, number, boolean, or symbol ALONG WITH function, object, and bigint.

  2. The section “The typeof type guard” may mislead the readers unless the author corrects those type with the lowercased types.

  3. Crazy language… The only way to really check for union typed classInstance is to have some unique filed name in it and do “if (uniqueFieldName in classInstance)”… *blarghhhhh

Leave a Reply