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?
![Vibration API]()
Many of the new APIs provided to us by browser vendors are more targeted toward the mobile user than the desktop user. One of those simple APIs the Vibration API. The Vibration API allows developers to direct the device, using JavaScript, to vibrate in...
![39 Shirts – Leaving Mozilla]()
In 2001 I had just graduated from a small town high school and headed off to a small town college. I found myself in the quaint computer lab where the substandard computers featured two browsers: Internet Explorer and Mozilla. It was this lab where I fell...
![MooTools Window Object Dumping]()
Ever want to see all of the information stored within the window property of your browser? Here's your chance.
The XHTML
We need a wrapper DIV that we'll consider a console.
The CSS
I like making this look like a command-line console.
The MooTools JavaScript
Depending on what you have loaded...
![Detect Vendor Prefix with JavaScript]()
Regardless of our position on vendor prefixes, we have to live with them and occasionally use them to make things work. These prefixes can be used in two formats: the CSS format (-moz-, as in -moz-element) and the JS format (navigator.mozApps). The awesome X-Tag project has...