Return a Default Value with Promises Using catch

By  on  

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?

Recent Features

Incredible Demos

  • By
    Introducing MooTools ScrollSide

    This post is a proof of concept post -- the functionality is yet to be perfected. Picture this: you've found yourself on a website that uses horizontal scrolling instead of vertical scrolling. It's an artistic site so you accept that the site scrolls left to right.

  • By
    Printing MooTools Accordion Items

    Sometimes we're presented with unforeseen problems when it comes to our JavaScript effects. In this case, I'm talking about printing jQuery and MooTools accordions. Each "closed" accordion content element has its height set to 0 which means it will be hidden when the...

Discussion

    Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!