refining the tuple calculations

haskell-experiments/src/Datalog/NaiveQE.hs

@@ -18,6 +18,9 @@ import Datalog.DatalogParser
 import Control.Exception
 import Data.Maybe
 import Utility.Utility
+import Control.Monad(guard)
+import Data.Set (Set)
+import Data.Set qualified as Set
 
 data (DatalogDB db) => NaiveQE db = NaiveQE 
   {
@@ -64,7 +67,13 @@ computeHerbrand db =
     amalgamateRelationSub newFacts relation = 
       foldr amalgamateRule newFacts (_rules relation) where
       amalgamateRule :: RelationRule -> NewFacts -> NewFacts
-      amalgamateRule (RelationRule headVars body) newFacts  = 
-        -- allMaps headVars (allConstants db)
-        newFacts
+      amalgamateRule (RelationRule headVars body) newFacts  =
+        newFacts where
+        (facts, changed) = newFacts
+        knownTuples :: Set [Constant] = _tuples $ facts Map.! (_name relation)
+        extraTuples = do
+          varmap <- allMaps headVars (Set.toList $ allConstants db)
+          let tuple = (\name -> varmap Map.! name) <$> headVars
+          guard $ not $ Set.member tuple knownTuples
+          return varmap