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?
![LightFace: Facebook Lightbox for MooTools]()
One of the web components I've always loved has been Facebook's modal dialog. This "lightbox" isn't like others: no dark overlay, no obnoxious animating to size, and it doesn't try to do "too much." With Facebook's dialog in mind, I've created LightFace: a Facebook lightbox...
![Regular Expressions for the Rest of Us]()
Sooner or later you'll run across a regular expression. With their cryptic syntax, confusing documentation and massive learning curve, most developers settle for copying and pasting them from StackOverflow and hoping they work. But what if you could decode regular expressions and harness their power? In...
![Scrolling “Go To Top” Link Using Dojo]()
One of the most popular code snippets of posted on my blog has been the scrolling "Go To Top" link snippet. The premise of the snippet is simple: once the user scrolls an element (usually the BODY element) past a given threshold, a "Go...
![Checkbox Filtering Using MooTools ElementFilter]()
When I first wrote MooTools ElementFilter, I didn't think much of it. Fast forward eight months later and I've realized I've used the plugin a billion times. Hell, even one of the "big 3" search engines is using it for their maps application.