AggregateError

By  on  

One of the big themes of the web these days is concurrency, which leads to accomplishing tasks asynchronously. In doing so, the possibility of multiple errors can occur. Instead of providing a generic error, optimally you'd provide a wealth of error information. TheAggregateError error lets developers throw multiple errors within one single Error. Let's see how it works.

To throw a single error that represents multiple errors, let's employ AggregateError:

const error = new AggregateError([
  new Error('ERROR_11112'),
  new TypeError('First name must be a string'),
  new RangeError('Transaction value must be at least 1'),
  new URIError('User profile link must be https'),
], 'Transaction cannot be processed')

Throwing an AggregateError gets you the following information:

error instanceof AggregateError // true
error.name // 'AggregateError'
error.message // 'Transaction cannot be processed'
error.errors // The array of errors

The AggregateError is incredibly useful when validating multiple sets of data; instead of throwing one error at a time, grouping them into one is ideal! AggregateError would be really useful in a Promise.any situation. Communicative, information-rich errors FTW!

Recent Features

Incredible Demos

  • By
    Flexbox Equal Height Columns

    Flexbox was supposed to be the pot of gold at the long, long rainbow of insufficient CSS layout techniques.  And the only disappointment I've experienced with flexbox is that browser vendors took so long to implement it.  I can't also claim to have pushed flexbox's limits, but...

  • By
    “Top” Watermark Using MooTools

    Whenever you have a long page worth of content, you generally want to add a "top" anchor link at the bottom of the page so that your user doesn't have to scroll forever to get to the top. The only problem with this method is...

Discussion

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