diff --git a/logic/languages/jetbrains.mps.logic/generator/template/main@generator.mps b/logic/languages/jetbrains.mps.logic/generator/template/main@generator.mps
index 6ca12dc8..025fbc1e 100644
--- a/logic/languages/jetbrains.mps.logic/generator/template/main@generator.mps
+++ b/logic/languages/jetbrains.mps.logic/generator/template/main@generator.mps
@@ -1265,7 +1265,7 @@
               <node concept="2OqwBi" id="6dMt3c5apcf" role="2Oq$k0">
                 <node concept="30H73N" id="6dMt3c5apcg" role="2Oq$k0" />
                 <node concept="3TrEf2" id="6dMt3c5apch" role="2OqNvi">
-                  <ref role="3Tt5mk" to="5j4j:7E86$tKsJfa" resolve="index" />
+                  <ref role="3Tt5mk" to="5j4j:4xOAf2nhhJX" resolve="position" />
                 </node>
               </node>
               <node concept="3x8VRR" id="6dMt3c5apci" role="2OqNvi" />
@@ -1352,7 +1352,7 @@
                         <node concept="3clFbF" id="7HUwyZaNQHE" role="3cqZAp">
                           <node concept="2OqwBi" id="7HUwyZaNQHF" role="3clFbG">
                             <node concept="3TrEf2" id="7HUwyZaNQHG" role="2OqNvi">
-                              <ref role="3Tt5mk" to="5j4j:7E86$tKsJfa" resolve="index" />
+                              <ref role="3Tt5mk" to="5j4j:4xOAf2nhhJX" resolve="position" />
                             </node>
                             <node concept="30H73N" id="7HUwyZaNQHH" role="2Oq$k0" />
                           </node>
@@ -1378,7 +1378,7 @@
               <node concept="2OqwBi" id="6dMt3c5apH5" role="2Oq$k0">
                 <node concept="30H73N" id="6dMt3c5apH6" role="2Oq$k0" />
                 <node concept="3TrEf2" id="6dMt3c5apH7" role="2OqNvi">
-                  <ref role="3Tt5mk" to="5j4j:7E86$tKsJfa" resolve="index" />
+                  <ref role="3Tt5mk" to="5j4j:4xOAf2nhhJX" resolve="position" />
                 </node>
               </node>
               <node concept="3w_OXm" id="6dMt3c5aq2r" role="2OqNvi" />
diff --git a/logic/languages/jetbrains.mps.logic/languageModels/editor.mps b/logic/languages/jetbrains.mps.logic/languageModels/editor.mps
index 74b6a80b..92dffa1a 100644
--- a/logic/languages/jetbrains.mps.logic/languageModels/editor.mps
+++ b/logic/languages/jetbrains.mps.logic/languageModels/editor.mps
@@ -2350,8 +2350,8 @@
           </node>
         </node>
         <node concept="3F1sOY" id="6p0DfM0nLOu" role="3EZMnx">
-          <ref role="1NtTu8" to="5j4j:7E86$tKsJfa" resolve="index" />
           <ref role="1k5W1q" node="7ksQUDZtGfa" resolve="Value" />
+          <ref role="1NtTu8" to="5j4j:4xOAf2nhhJX" resolve="position" />
           <node concept="2w$q5c" id="4bWqD4CreUJ" role="3xwHhi">
             <node concept="2aJ2om" id="4bWqD4CreUK" role="2w$qW5">
               <ref role="2$4xQ3" node="4bWqD4CreCD" resolve="EXPRESSION" />
@@ -2368,7 +2368,7 @@
                   <node concept="Bykcj" id="30XHGaOG64O" role="2OqNvi">
                     <node concept="1aIX9F" id="30XHGaOG64P" role="1xVPHs">
                       <node concept="26LbJo" id="30XHGaOG64Q" role="1aIX9E">
-                        <ref role="26LbJp" to="5j4j:7E86$tKsJfa" resolve="index" />
+                        <ref role="26LbJp" to="5j4j:4xOAf2nhhJX" resolve="position" />
                       </node>
                     </node>
                   </node>
@@ -3203,7 +3203,7 @@
   </node>
   <node concept="IW6AY" id="4hPXq9Jm69G">
     <property role="3GE5qa" value="logical" />
-    <ref role="aqKnT" to="5j4j:7E86$tKsHeX" resolve="AbstractLogicalVariable" />
+    <ref role="aqKnT" to="5j4j:7E86$tK_OxQ" resolve="LogicalVariableReference" />
     <node concept="1Qtc8_" id="4hPXq9Jm69H" role="IW6Ez">
       <node concept="3cWJ9i" id="4hPXq9Jm69I" role="1Qtc8$">
         <node concept="CtIbL" id="4hPXq9Jm69J" role="CtIbM">
@@ -3229,7 +3229,7 @@
                 <node concept="2OqwBi" id="4hPXq9Jm69V" role="2Oq$k0">
                   <node concept="7Obwk" id="4hPXq9Jm69Z" role="2Oq$k0" />
                   <node concept="3TrEf2" id="4hPXq9Jm69X" role="2OqNvi">
-                    <ref role="3Tt5mk" to="5j4j:7E86$tKsJfa" resolve="index" />
+                    <ref role="3Tt5mk" to="5j4j:4xOAf2nhhJX" resolve="position" />
                   </node>
                 </node>
                 <node concept="3w_OXm" id="4hPXq9Jm69Y" role="2OqNvi" />
@@ -3254,7 +3254,7 @@
                   <node concept="2OqwBi" id="4hPXq9Jm6a9" role="2Oq$k0">
                     <node concept="7Obwk" id="4hPXq9Jm6af" role="2Oq$k0" />
                     <node concept="3TrEf2" id="4hPXq9Jm6ab" role="2OqNvi">
-                      <ref role="3Tt5mk" to="5j4j:7E86$tKsJfa" resolve="index" />
+                      <ref role="3Tt5mk" to="5j4j:4xOAf2nhhJX" resolve="position" />
                     </node>
                   </node>
                   <node concept="2DeJnY" id="4hPXq9Jm6ac" role="2OqNvi" />
diff --git a/logic/languages/jetbrains.mps.logic/languageModels/structure.mps b/logic/languages/jetbrains.mps.logic/languageModels/structure.mps
index 09b0bdbf..3413131b 100644
--- a/logic/languages/jetbrains.mps.logic/languageModels/structure.mps
+++ b/logic/languages/jetbrains.mps.logic/languageModels/structure.mps
@@ -256,7 +256,7 @@
     <property role="3GE5qa" value="logical" />
     <property role="TrG5h" value="ExpressionLogicalVariable" />
     <property role="EcuMT" value="8829335963591530299" />
-    <ref role="1TJDcQ" node="7E86$tKsHeX" resolve="AbstractLogicalVariable" />
+    <ref role="1TJDcQ" node="7E86$tKsl45" resolve="LogicalItem" />
     <node concept="1TJgyj" id="7E86$tKt5BI" role="1TKVEi">
       <property role="20lmBu" value="aggregation" />
       <property role="20kJfa" value="expression" />
@@ -303,6 +303,12 @@
       <property role="IQ2ns" value="8829335963593822893" />
       <ref role="20lvS9" node="7E86$tKtfM3" resolve="LogicalVariableDeclaration" />
     </node>
+    <node concept="1TJgyj" id="4xOAf2nhhJX" role="1TKVEi">
+      <property role="IQ2ns" value="5220966027126709245" />
+      <property role="20lmBu" value="aggregation" />
+      <property role="20kJfa" value="position" />
+      <ref role="20lvS9" node="7E86$tKskWj" resolve="LogicalValue" />
+    </node>
   </node>
   <node concept="1TIwiD" id="1mP5b6jNC0S">
     <property role="3GE5qa" value="logical" />
diff --git a/logic/languages/jetbrains.mps.logic/languageModels/typesystem.mps b/logic/languages/jetbrains.mps.logic/languageModels/typesystem.mps
index 7f3fb0ee..d1d7fb49 100644
--- a/logic/languages/jetbrains.mps.logic/languageModels/typesystem.mps
+++ b/logic/languages/jetbrains.mps.logic/languageModels/typesystem.mps
@@ -299,7 +299,7 @@
               <ref role="1YBMHb" node="2c3nq4GQw_H" resolve="lvr" />
             </node>
             <node concept="3TrEf2" id="7dgRGU4B5pQ" role="2OqNvi">
-              <ref role="3Tt5mk" to="5j4j:7E86$tKsJfa" resolve="index" />
+              <ref role="3Tt5mk" to="5j4j:4xOAf2nhhJX" resolve="position" />
             </node>
           </node>
           <node concept="3w_OXm" id="7dgRGU4B5O8" role="2OqNvi" />
diff --git a/typesystem2/languages/jetbrains.mps.lang.typesystem2/generator/template/main@generator.mps b/typesystem2/languages/jetbrains.mps.lang.typesystem2/generator/template/main@generator.mps
index 517dbda8..0bc7668f 100644
--- a/typesystem2/languages/jetbrains.mps.lang.typesystem2/generator/template/main@generator.mps
+++ b/typesystem2/languages/jetbrains.mps.lang.typesystem2/generator/template/main@generator.mps
@@ -11332,7 +11332,7 @@
               <node concept="2OqwBi" id="75vUFrSLwwz" role="2Oq$k0">
                 <node concept="30H73N" id="75vUFrSLww$" role="2Oq$k0" />
                 <node concept="3TrEf2" id="75vUFrSLww_" role="2OqNvi">
-                  <ref role="3Tt5mk" to="5j4j:7E86$tKsJfa" resolve="index" />
+                  <ref role="3Tt5mk" to="5j4j:4xOAf2nhhJX" resolve="position" />
                 </node>
               </node>
               <node concept="3w_OXm" id="75vUFrSLwwA" role="2OqNvi" />
@@ -11394,7 +11394,7 @@
               <node concept="2OqwBi" id="75vUFrSLx4u" role="2Oq$k0">
                 <node concept="30H73N" id="75vUFrSLx4v" role="2Oq$k0" />
                 <node concept="3TrEf2" id="75vUFrSLx4w" role="2OqNvi">
-                  <ref role="3Tt5mk" to="5j4j:7E86$tKsJfa" resolve="index" />
+                  <ref role="3Tt5mk" to="5j4j:4xOAf2nhhJX" resolve="position" />
                 </node>
               </node>
               <node concept="3x8VRR" id="75vUFrSLx4x" role="2OqNvi" />
@@ -11424,7 +11424,7 @@
                         <node concept="3clFbF" id="7HUwyZaPVji" role="3cqZAp">
                           <node concept="2OqwBi" id="7HUwyZaPVjj" role="3clFbG">
                             <node concept="3TrEf2" id="7HUwyZaPVjk" role="2OqNvi">
-                              <ref role="3Tt5mk" to="5j4j:7E86$tKsJfa" resolve="index" />
+                              <ref role="3Tt5mk" to="5j4j:4xOAf2nhhJX" resolve="position" />
                             </node>
                             <node concept="30H73N" id="7HUwyZaPVjl" role="2Oq$k0" />
                           </node>
@@ -13304,7 +13304,7 @@
               <node concept="2OqwBi" id="452KZTbxZcL" role="2Oq$k0">
                 <node concept="30H73N" id="452KZTbxZcM" role="2Oq$k0" />
                 <node concept="3TrEf2" id="452KZTbxZcN" role="2OqNvi">
-                  <ref role="3Tt5mk" to="5j4j:7E86$tKsJfa" resolve="index" />
+                  <ref role="3Tt5mk" to="5j4j:4xOAf2nhhJX" resolve="position" />
                 </node>
               </node>
               <node concept="3w_OXm" id="452KZTbxZcO" role="2OqNvi" />
@@ -13412,7 +13412,7 @@
                             <node concept="3clFbF" id="452KZTbxZdc" role="3cqZAp">
                               <node concept="2OqwBi" id="452KZTbxZdd" role="3clFbG">
                                 <node concept="3TrEf2" id="452KZTbxZde" role="2OqNvi">
-                                  <ref role="3Tt5mk" to="5j4j:7E86$tKsJfa" resolve="index" />
+                                  <ref role="3Tt5mk" to="5j4j:4xOAf2nhhJX" resolve="position" />
                                 </node>
                                 <node concept="30H73N" id="452KZTbxZdf" role="2Oq$k0" />
                               </node>
@@ -13437,7 +13437,7 @@
               <node concept="2OqwBi" id="452KZTbxZdJ" role="2Oq$k0">
                 <node concept="30H73N" id="452KZTbxZdK" role="2Oq$k0" />
                 <node concept="3TrEf2" id="452KZTbxZdL" role="2OqNvi">
-                  <ref role="3Tt5mk" to="5j4j:7E86$tKsJfa" resolve="index" />
+                  <ref role="3Tt5mk" to="5j4j:4xOAf2nhhJX" resolve="position" />
                 </node>
               </node>
               <node concept="3x8VRR" id="452KZTbxZdM" role="2OqNvi" />