How regex rules work?

[Cerebellum-ITM]

I've been creating rules for my folders and icons. Sometimes they work without problems other times it seems to ignore them all leaving the "." ruler icon. In some messages I have seen that they use something like "folder/*" the name can change and does it mean that it applies only to that directory? Could someone explain to me how to apply my rules correctly. Thanks for your comments

[iamzweiaa]

me too, same here
like i have the daily note named as YYYY-MM-DD
and in regex i put it as ^\d{4}-\d{2}-\d{2}$
but it doesn't work

[CGPGrey]

+1

Really interested in the custom rules, but can't get them to work.

[CHerSun]

Would love a bit of clarification too. Trying to add icon to external links (starting with http(s) - ^https?:\/ is the pattern)

Update: tested with just . pattern - all file-related links were highlighted, but not external links to web-pages. Looks like the thing I wanted is not achievable