Return a Default Value with Promises Using catch
Last week I tweeted all of you looking for your best JavaScript Array and Promise tricks, and as always, it didn't disappoint -- I learned quite a bit!
Today's JavaScript Promise trick is brought to you by Claudio Semeraro: how to use catch to set a default value instead of a try/catch:
// Instead of wrapping this block in a try/catch...
const result = await new Promise(
(resolve, reject) => reject("Because Stone Cold said so")
)
// ...use catch to set the default value (100)
.catch(() => 100);
As a trick I really like what's this brings; as far as readability and maintenance, if you don't know the trick, you might get confused. What do you think?
![CSS Gradients]()
With CSS border-radius, I showed you how CSS can bridge the gap between design and development by adding rounded corners to elements. CSS gradients are another step in that direction. Now that CSS gradients are supported in Internet Explorer 8+, Firefox, Safari, and Chrome...
![9 More Mind-Blowing WebGL Demos]()
With Firefox OS, asm.js, and the push for browser performance improvements, canvas and WebGL technologies are opening a world of possibilities. I featured 9 Mind-Blowing Canvas Demos and then took it up a level with 9 Mind-Blowing WebGL Demos, but I want to outdo...
![WebSocket and Socket.IO]()
My favorite web technology is quickly becoming the WebSocket API. WebSocket provides a welcomed alternative to the AJAX technologies we've been making use of over the past few years. This new API provides a method to push messages from client to server efficiently...
![Create a Simple Dojo Accordion]()
Let's be honest: even though we all giggle about how cheap of a thrill JavaScript accordions have become on the web, they remain an effective, useful widget. Lots of content, small amount of space. Dojo's Dijit library provides an incredibly simply method by which you can...