Regular expression tutorial

Can anybody recommend a good tutorial for regex? I used it in a limited fashion (translating URLs on a MS web server) about 20 years ago but have forgotten more than I ever knew I think. Something that shows syntax and allows me to create one and test the results would be perfect and an offline one would be better than perfect.

Out of curiosity, what's your use case(s) for Joplin?

I like regex101 for trying out patterns. You can test it on a text, and get an explanation of the different components in your pattern.

As for a tutorial, I don't have a favourite, but ChatGPT can actually be helpful sometimes (describe what you want, test the result on regex101, iterate and improve). Here's a short cheatsheet.

I see others doing searches saying "or use regex and . . ." so I was wondering if it might be worthwhile, and with time on my hands I think it's something I might find a use for. Maybe not today but who knows?

Unfortunately Joplin has limited support for regular expression so in that area it's pretty basic.
I don't know where you would be able to find a specific list of regular Expressions that are explicitly supported.

Actually, I'm pretty sure there is better support for Boolean expression searching. I would Google that and cross it with Joplin and I just used perplexity and it gave me a bunch of information on Boolean expressions and made it clear that Joplin does not have full support for regular expressions.

Actually, I recently noticed that the beta editor supports regular expressions when searching within a note. At the bottom of the editor I found this:

I saw it as well in the "Search and Replace" plugin and thought it might be useful. It's not of any real importance, I saw it and wondered if it would improve searching.