Created
December 21, 2018 14:30
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;; Because in formal logic, ∀x.P(x) = ¬∃x.¬P(x) | |
(d/q '[:find ?id | |
:in $ [?interest ...] | |
:where | |
[?a :account/id ?id] | |
(not-join [?a ?interest] | |
[?a :account/interest ?i] | |
(not [(= ?i ?interest)]))]) | |
;; It is harder to understand when you bind interest as above if you | |
;; are thinking in terms of iterative binding (but it still should | |
;; work!) If you make 'interests' a data source, it looks like this: | |
(d/q '[:find ?id | |
:in $ $interests | |
:where | |
[?a :account/id ?id] | |
(not-join [?a] | |
[?a :account/interest ?i] | |
(not [$interests ?i]))] | |
db | |
(map vector interests)) |
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