I hope I got the right category.
The blacklist help page (found at wiki #1008 as well as at /help/blacklist) currently features this bit of text:
Tag Operators
You can also use 'operators' like - in your blacklist, just as you might in a search. The tricky part is that using a - suggests that you WANT to see that thing, so getting it right make take a bit of time to get used to.
-female
This, for example, ensures that any picture NOT tagged with 'female' will not display. This is more useful then blacklisting 'male' if you don't mind seeing pictures of males, as long as there are females in the image.
pokémon -pikachu
This example would remove ALL pokémon images from view, UNLESS pikachu is also tagged. This is useful if you only like one specific type of something. (alternatively: canine -fox, scalie -breasts)
fox -wolf -lion
This one is a bit more complicated: This would hide all fox images that do not have wolves, or do not have lions. So a picture of fox alone, or a fox and a bear/goat/horse/etc would be removed, but a fox and a lion, or a fox and a wolf would be kept.
I myself have been trying to accomplish blacklisting 'the_amazing_world_of_gumball' if and only if it does not contain these tags too: 'nicole_watterson solo'.
In other words, only allow 'the_amazing_world_of_gumball' posts that match this search pattern: 'the_amazing_world_of_gumball nicole_watterson solo'.
Even more simply, the only Gumball posts I want to see are those with Nicole alone.
I had this at first:
the_amazing_world_of_gumball -nicole_watterson -solo
But as the help text says, it only blocks one or the other combo of regular and minused tag.
And I figured it out eventually! Putting this in my blacklist makes it work perfectly:
the_amazing_world_of_gumball -nicole_watterson the_amazing_world_of_gumball -solo
With these lines in place, the only posts displayed out of Gumball posts are those that contain Nicole Watterson alone.
I am sure others have struggled with this problem too. The Combined Tags and One tag per line sections do seem to imply this solution, but it's not very clear.
So I'd propose something like the following:
Tag Operators
You can also use 'operators' like - in your blacklist, just as you might in a search. The tricky part is that using a - suggests that you WANT to see that thing, so getting it right make take a bit of time to get used to.
-female
This, for example, ensures that any picture NOT tagged with 'female' will not display. This is more useful than blacklisting 'male' if you don't mind seeing pictures of males, as long as there are female characters in the image.
pokémon -pikachu
This example would remove ALL pokémon images from view, UNLESS pikachu is also tagged. This is useful if you only like one specific type of something. (alternatively: canine -fox, scalie -breasts)
fox -wolf -lion
This one is a bit more complicated: This would hide all fox images that do not have wolves, or do not have lions. So a picture of a fox alone, or a fox and a bear/goat/horse/etc would be removed, but a fox and a lion, or a fox and a wolf would be kept.
fox -wolf fox -lion
This one would hide all fox images that do not have wolves AND do not have lions. Only the pictures where a fox is with both a lion and a wolf would be kept; any other picture of a fox would be removed. Unlike the previous example, this one makes sure that both the wolf and lion tags are present.
You can surely phrase the new example's description better, though, some of you probably being native speakers and all.
I hope you'll consider this addition; it would have been very helpful to me, had it been there already when I needed it!