Regular Expression Match Groups

By  on  

Regular expressions are incredibly powerful but can be difficult to maintain. They're a skill you learn on the job and, when the suits walk by, make you look incredibly smart if you have a few up on your screen. How can we solve the maintainability problem? With a match groups, as Addy Osmani enlightened me about last week:

https://twitter.com/addyosmani/status/1386031624232456194

Look at the ?<descriptor> pattern, with the descriptor being a meaningful name that you want to give to a give group. With the group usage, you can more intelligently handle match results:

const re = /(?\d{4})-(?\d{2})-(?\d{2})/;
const result = re.exec('2021-04-26');

// Deconstructing from result.groups
const { year, month, day } = result.groups;

// Using array syntax
const [, year, month, day] = result;

The only real downside of using this strategy is that most developers probably don't know about it. You could also complain that it makes the regular expression longer. In the end, however, maintainability rules the day, and I love that Addy shared this tip with us!

Recent Features

  • By
    CSS Gradients

    With CSS border-radius, I showed you how CSS can bridge the gap between design and development by adding rounded corners to elements.  CSS gradients are another step in that direction.  Now that CSS gradients are supported in Internet Explorer 8+, Firefox, Safari, and Chrome...

  • By
    Write Better JavaScript with Promises

    You've probably heard the talk around the water cooler about how promises are the future. All of the cool kids are using them, but you don't see what makes them so special. Can't you just use a callback? What's the big deal? In this article, we'll...

Incredible Demos

  • By
    GitHub-Style Sliding Links

    GitHub seems to change a lot but not really change at all, if that makes any sense; the updates come often but are always fairly small. I spotted one of the most recent updates on the pull request page. Links to long branch...

  • By
    CSS Columns

    One major gripe that we've always had about CSS is that creating layouts seems to be more difficult than it should be. We have, of course, adapted and mastered the techniques for creating layouts, but there's no shaking the feeling that there should be a...

Discussion

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