Trying to add the =/= constraint to µKanren based on William Byrd's lecture: Uncourse #8
First attempt seems to be working ok but isn't efficient and the code looks ugly (doesn't fit with the very elegant minimal muKanren style), hope to make it cleaner.
Bugs
Noticed a bug in this when i tried rembero and it was failing when it shouldn't have. I cut the test case down to this:
> (run* (q) (fresh (x xs) (== '(a b) `(,x . ,xs)) (=/= 'c x)))
((_.0 (and (or))))
> (run* (q) (fresh (x xs) (== '(a b) `(,x . ,xs)) (=/= 'c x) (== q `(,x ,xs))))
()
and I think the bug came from an edge case in de-morgans law applied to an empty or like (and (or)). So the fix was to filter out empties.
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