Tag Retention Rule: more complex repository filters

[hostalp]

I'd like to be able to enter something like the following tag retention rule repository filter:

a/b,c/d

This doesn't work and gives a HTTP 500 response due to the incorrect synax.
From #14259 and #14510 and also https://github.com/bmatcuk/doublestar#patterns I learned that a/{b} should work when dealing with / in the pattern and yes it does really work. However I don't seem to be able to combine both parts of the pattern into one.

• a/{b},c/{d} doesn't work (but doesn't cause any syntax error), nothing is found to be processed by such rule
• {a/{b},c/{d}} can't be entered into the input field due to changes in run retention rule failed with special pattern #14259 I assume as one of the outer curly brackets is automatically removed
• some other experiments like {a/{b}},{c/{d}} were also unsuccessful (can't be entered either)

Is there any way how to enter such expression and get it to work? Or do I really have to create separate rules for each of those variants?

Note that when reading https://github.com/bmatcuk/doublestar#performance I noticed some mention of nested alts so it looks like some form of nesting might work.

[chlins]

Why not setup multiple rules to satisfy your requirements?

[hostalp]

Because there's a limit for the amount of rules that could be then easily hit (15).