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

  • By
    6 Things You Didn’t Know About Firefox OS

    Firefox OS is all over the tech news and for good reason:  Mozilla's finally given web developers the platform that they need to create apps the way they've been creating them for years -- with CSS, HTML, and JavaScript.  Firefox OS has been rapidly improving...

  • By
    5 Awesome New Mozilla Technologies You’ve Never Heard Of

    My trip to Mozilla Summit 2013 was incredible.  I've spent so much time focusing on my project that I had lost sight of all of the great work Mozillians were putting out.  MozSummit provided the perfect reminder of how brilliant my colleagues are and how much...

Incredible Demos

Discussion

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