New question:
I created several user-categories to group the entries in taglike #fanficcat. (For several reasons, I prefer to leave the column itself as nonhierarchical entries.)
To find books that have entries not present in the categories, I search for
#fanficcat:true AND @Fanfiction.Fandoms:.false. Is it possible to also check this with a template?
EDIT:
Code:
program:
if
$#fanficcat
&& !'Fandom' inlist user_categories()
then
'aaaa'
fi