JavaScript Numeric Separators

By  on  

Writing good code is important -- writing code that's easily human readable is a next level skill. It's not often that APIs are introduced whose seemingly only useful function is making code more readable, but let me introduce you to JavaScript numeric separators: an API that lets developers use underscores to make numbers more readable!

Consider the following number in your code:

// No commas for numbers in JavaScript
const oneHundredThousand = 100000;

Large numbers have always been difficult to mentally parse for engineers, so using underscores to make code more readable is a total win:

const oneMillion = 1_000_000; // 1000000
const decimals = 1_000_00.01_02_03 // 100000.010203

The only real rule with numeric separators is that the number cannot start or end with an underscore.

Numeric separators within JavaScript seem like spec creators gifting developers a feature. As an engineer, I'll take all I can get. You never stop learning in the world of JavaScript!

Recent Features

  • By
    fetch API

    One of the worst kept secrets about AJAX on the web is that the underlying API for it, XMLHttpRequest, wasn't really made for what we've been using it for.  We've done well to create elegant APIs around XHR but we know we can do better.  Our effort to...

  • By
    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...

Incredible Demos

  • By
    CSS Triangles

    I was recently redesigning my website and wanted to create tooltips.  Making that was easy but I also wanted my tooltips to feature the a triangular pointer.  I'm a disaster when it comes to images and the prospect of needing to make an image for...

  • By
    Create a Twitter AJAX Button with MooTools, jQuery, or Dojo

    There's nothing like a subtle, slick website widget that effectively uses CSS and JavaScript to enhance the user experience.  Of course widgets like that take many hours to perfect, but it doesn't take long for that effort to be rewarded with above-average user retention and...

Discussion

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