Topic: Boolean logic implications? Are they a thing?

Most of the implications I'm aware of use the format:

tag1 → tag2

Which is simple, easy-to-use, and fills the vast majority of use cases. Most sites don't even have that.

But... does e6's tag engine also do Boolean logic to the tune of:

multi-tag search → single tag

I know that sounds unnecessarily complicated, but I really think it could have use cases.

For example. A user might put in a request like:

sonic_the_hedgehog -alternate_species → hedgehog

Given the wiki for alternate_species, it seems to me like that implication would be much safer than the standard format (sonic_the_hedgehog→hedgehog), because there are, in fact discrepancies like post #5427295, to which the sonic_the_hedgehog tag clearly applies, but the hedgehog tag clearly doesn't, which would be unachievable with the simpler implication solution. But I don't see any such issue with the search→tag solution, and it seems like it could save a lot of manual tagging, and avoid any human error that might come with it.

Similar for other character -alternate_species implications and character -crossgender→(default gender).

But it could also go further. Consider:

scalie solo fur -fur_(fabric) → furred_scalie

As it stands, there are tens of thousands posts in the search (scalie solo fur -furred_scalie -fur_(fabric)), which all seem to be negligently tagged - either they aren't scalie, lack fur, are a furred scalie, the only fur present is used as fabric or feature multiple characters one of which has fur but isn't scalie and another of which vice-versa (in which case the solo tag shouldn't apply).

Or:

bird smile -unusual_mouth → beak

Since most images of smiling birds on this site seem to have beaks, whether already tagged as such or not, and I would opine counterexamples like post #6243497 may warrant the unusual_mouth tag.

I might think of other use cases later... but already the above examples seem to describe a lot of posts.

Does e6 already have this functionality? If not, would introducing it interfere with other functionalities, or be more difficult to code than e6 has means to implement? Or are there other reasons why it would be unwise to allow such implication formats, such as ways they could be misused or expectations people could get complacent about if no one is looking for things like that manually? Would there be a better format for representing such implications?

Any feedback, whether to enlighten, inquire, refine or refute, would be appreciated.

This doesn't exist, and this is not something that can exist in most cases; remember stuff like multi-panel comics could easily violate this. You can see the times I have previously discussed a tag validator that offers suggestions on my profile page, but definitives aren't feasible.

aacafah said:
... stuff like multi-panel comics could easily violate this...

I mean, that would invalidate some of the examples I provided, but in cases where I included negative search terms, wouldn't that term be present in at least one panel, thus preventing the implication from being accidentally triggered? And couldn't -comic be added to the search query to avoid unwanted implications (even if it loses a few of the desired ones)?

aacafah said:
...You can see the times I have previously discussed...

That sounds cool. Link?

On my profile page.