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
    Page Visibility API

    One event that's always been lacking within the document is a signal for when the user is looking at a given tab, or another tab. When does the user switch off our site to look at something else? When do they come back?

Incredible Demos

  • By
    dwImageProtector Plugin for jQuery

    I've always been curious about the jQuery JavaScript library. jQuery has captured the hearts of web designers and developers everywhere and I've always wondered why. I've been told it's easy, which is probably why designers were so quick to adopt it NOT that designers...

  • By
    AJAX For Evil:  Spyjax with jQuery

    Last year I wrote a popular post titled AJAX For Evil: Spyjax when I described a technique called "Spyjax": Spyjax, as I know it, is taking information from the user's computer for your own use — specifically their browsing habits. By using CSS and JavaScript, I...

Discussion

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