Multiple occurrences of query vars in pattern and aggregates

tonsky / datascript

Immutable database and Datalog query engine for Clojure, ClojureScript and JS

Eclipse Public License 1.0

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Open zoren opened 2 years ago

zoren commented 2 years ago

With this query:

(q '[:find (count ?e) .
     :with ?i
     :where [?e :r ?e ?i]]
   [[1 :r 1 10]
    [2 :r 1 11]])

I get 1 with Datomic but 2 in datascript. It appears the test for two occurrences of a query variable is tested too late.

tonsky commented 2 years ago

Looks like it. Related: #336

refset commented 1 year ago

I think this self-unification issue is related too: https://github.com/tonsky/datascript/issues/240