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?
![Responsive Images: The Ultimate Guide]()
Chances are that any Web designers using our Ghostlab browser testing app, which allows seamless testing across all devices simultaneously, will have worked with responsive design in some shape or form. And as today's websites and devices become ever more varied, a plethora of responsive images...
![9 Mind-Blowing WebGL Demos]()
As much as developers now loathe Flash, we're still playing a bit of catch up to natively duplicate the animation capabilities that Adobe's old technology provided us. Of course we have canvas, an awesome technology, one which I highlighted 9 mind-blowing demos. Another technology available...
![Google-Style Element Fading Using MooTools or jQuery]()
Google recently introduced an interesting effect to their homepage: the top left and top right navigation items don't display until you move your mouse or leave the search term box. Why? I can only speculate that they want their homepage as...
![Page Visibility API]()
One event that's always been lacking within the document is a signal for when the user is looking at a given tab, or another tab. When does the user switch off our site to look at something else? When do they come back?