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

Incredible Demos

  • By
    CSS Kwicks

    One of the effects that made me excited about client side and JavaScript was the Kwicks effect.  Take a list of items and react to them accordingly when hovered.  Simple, sweet.  The effect was originally created with JavaScript but come five years later, our...

  • By
    dwClickable:  Entire Block Clickable Using MooTools 1.2

    I recently received an email from a reader who was really impressed with Block Clickable, a jQuery script that took the link within a list item and made the entire list item clickable. I thought it was a neat script so I...

Discussion

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