Clojurians Log v2

Is this a correctness bug or does Datalevin have different semantics from Datascript / Datomic re. unifying _ variables in queries?

(require '[datalevin.core :as d])

(d/q '[:find ?x ?y
       :where
       [_ :foo ?x]
       [_ :bar ?y]]
  (d/db-with (d/empty-db)
    [{:foo 1}
     {:bar 2}
     {:foo 3 :bar 4}]))
;; => #{[3 4]}

;; Datascript returns:
;; => #{[3 4] [1 4] [1 2] [3 2]}