Stage 1 · Lesson 8 of 9
Errors in sync and async code
Wrap awaited calls, the ones built on , in try and catch. Use finally for clean-up such as hiding a spinner, whatever happened. Throw Error objects rather than strings, so you keep a showing where it failed.
In the caught value has the type unknown until you check it. Know which failures do not throw at all. fetch finishes normally for a 404 or 500 error from the server, so you must check response.ok yourself.
Catch errors where the app can react, such as showing a retry button, not inside every helper.
Common trapan empty catch that swallows the error, leaving a blank screen and nothing in the logs.
A question to check yourself, an AI practice session and 2 cheat sheet entries come with the full roadmap. Unlock
Resources for this stage
Start with· follow one of these
- CoursePaidGrokking JavaScript Fundamentals
Design Gurus · Beginner · $50
Beginner JavaScript with an exercise after most lessons
- GuideFreeJavaScript.info
Ilya Kantor
Free and thorough: Part 1 is the language, skip the browser chapters in Part 2