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Getting Started with Regular Expressions

Nick Taylor on July 18, 2021

Regular expressions (regex) are one of those things that folks seem to make fun of most of the time because they don't understand them, or partiall...

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mkt • Jul 18 '21 • Edited

Nice Article. Will there be more? Was thinking about writing a beginners guide myself.

I'd like to emphasize a bit more how tools like regextester.com regex101.com can be a great resource to learn by looking at the existing expressions or playing with your own ones and then hovering with your mouse over the expression to get an explanation of what's happening.

(btw: s missing in "Matering..." link at the end)

Nick Taylor • Jul 19 '21

This was a one off, but if folks want to see more about regexes, I'd be happy to write some more about them. 😎

If you have a beginner's guide in mind, go for it! A different perspective on a topic can only be good for the community!

Also, thanks for catching the typo! I wrote this post late last night lol.

Lucia Cerchie • Jul 19 '21

Would love a beginner's guide!

mkt • Jul 19 '21

Fascinating how just one short comment like yours gets one out of procrastination and into being productive! :D

Lucia Cerchie • Jul 19 '21

media.giphy.com/media/rhC8duvjyYNh...

mkt • Jul 24 '21 • Edited

dev.to/mktcode/regular-expressions...

I found there are already so many good resources for technical people, so I tried to write something specifically for non-technical people. Hope it works.

Samuel Roland • Jul 25 '21

Hey
Thanks for the article! Great introduction!

I wanted to write it on it because I struggled to understand it at the start, but didn't how to start because it's pretty broad subject (to understand I had to learn several not intuitive concepts and make a lot of tests). Now I have some good basics. I didn't know the "+?" combination trick that's great.

The app that helped me a lot (and that you can maybe add to the resource list) is regexr.com (it's opensource!). You can even save your patterns (like this one, publish and browse existing patterns, read a cheat sheet, and the colours and interface really help to understand. I really like the "explanations on hover with selections".
Another websites that looks fun learn-regex.com and regex-one.com.

A few suggestions to enhance it:

Explain the goal of regex (like search, validate or replace strings).
To say or give example on how to run regex (depends on the languages is important to mention too).
Add some examples for simple password validation.
Mention that often there is no need to write complex Regex for common use cases (such as email or validation) because they already exist (just need to search and choose one, especially for email where there is no perfect regex AFAIK). Sometimes they are constants or functions that already exist in languages to validate them.