From: Hannu Niemistö <hannu.niemisto@semantum.fi>
Date: Mon, 24 Jul 2017 08:15:12 +0000 (+0300)
Subject: (refs #7375) Replace collectRefs by CollectRefsVisitor
X-Git-Tag: v1.31.0~264^2~37^2
X-Git-Url: https://gerrit.simantics.org/r/gitweb?a=commitdiff_plain;h=refs%2Fchanges%2F51%2F751%2F1;p=simantics%2Fplatform.git

(refs #7375) Replace collectRefs by CollectRefsVisitor

Change-Id: I77bf548a062bb365f43284778845678fb50341d5
---

diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/compilation/TypeChecking.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/compilation/TypeChecking.java
index 58bb98a41..52b8692d8 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/compilation/TypeChecking.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/compilation/TypeChecking.java
@@ -408,7 +408,7 @@ public class TypeChecking {
                 for(TransformationRule rule : module.getRules())
                     for(Query[] queries : rule.sections.values())
                         for(Query query : queries)
-                            query.collectRefs(allRefs, refs);                
+                            query.collectRefs(allRefs, refs);
             }
             
             @Override
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/CHRLiteral.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/CHRLiteral.java
index e8bb00a6e..2697ea08f 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/CHRLiteral.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/CHRLiteral.java
@@ -112,14 +112,6 @@ public class CHRLiteral extends Symbol {
         }
     }
 
-    public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        for(Expression parameter : parameters)
-            parameter.collectRefs(allRefs, refs);
-        if(typeConstraintEvidenceParameters != null)
-            for(Expression parameter : typeConstraintEvidenceParameters)
-                parameter.collectRefs(allRefs, refs);
-    }
-
     public void checkType(TypingContext context) {
         if(relation == SpecialCHRRelation.EXECUTE) {
             if(parameters.length != 1)
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/CHRQuery.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/CHRQuery.java
index 777dc9f6c..8bba6697d 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/CHRQuery.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/CHRQuery.java
@@ -31,11 +31,6 @@ public class CHRQuery extends Symbol {
             literal.resolve(context);
     }
 
-    public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        for(CHRLiteral literal : literals)
-            literal.collectRefs(allRefs, refs);
-    }
-
     public void checkType(TypingContext context) {
         for(CHRLiteral literal : literals)
             literal.checkType(context);
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/CHRRule.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/CHRRule.java
index 31d0ec48c..67b30b221 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/CHRRule.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/CHRRule.java
@@ -57,11 +57,6 @@ public class CHRRule extends Symbol {
         existentialVariables = context.popExistentialFrame();
     }
 
-    public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        head.collectRefs(allRefs, refs);
-        body.collectRefs(allRefs, refs);
-    }
-
     public void checkType(TypingContext context) {
         for(Variable variable : existentialVariables)
             variable.setType(Types.metaVar(Kinds.STAR));
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/CHRRuleset.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/CHRRuleset.java
index 9eca12aa9..805e781e7 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/CHRRuleset.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/CHRRuleset.java
@@ -122,13 +122,6 @@ public class CHRRuleset extends Symbol {
         }*/
     }
 
-    public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        for(IncludeStatement include : includes)
-            include.value.collectRefs(allRefs, refs);
-        for(CHRRule rule : rules)
-            rule.collectRefs(allRefs, refs);
-    }
-
     public void checkType(TypingContext context) {
         for(IncludeStatement include : includes)
             include.value = include.value.checkType(context, include.ruleset.runtimeRulesetType);
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/equation/EqBasic.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/equation/EqBasic.java
index 67608de2d..08b1a0726 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/equation/EqBasic.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/equation/EqBasic.java
@@ -53,12 +53,6 @@ public class EqBasic extends Equation {
         right = right.checkType(context, left.getType());
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        left.collectRefs(allRefs, refs);
-        right.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars) {
         left.collectVars(allVars, vars);
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/equation/EqGuard.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/equation/EqGuard.java
index 2e434b461..5dac9fce4 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/equation/EqGuard.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/equation/EqGuard.java
@@ -48,11 +48,6 @@ public class EqGuard extends Equation {
         guard = guard.checkIgnoredType(context);
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        guard.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars) {
         guard.collectVars(allVars, vars);
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/equation/Equation.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/equation/Equation.java
index dcf11a3e6..ca4102c96 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/equation/Equation.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/equation/Equation.java
@@ -4,7 +4,6 @@ import org.simantics.scl.compiler.elaboration.contexts.ReplaceContext;
 import org.simantics.scl.compiler.elaboration.contexts.TranslationContext;
 import org.simantics.scl.compiler.elaboration.contexts.TypingContext;
 import org.simantics.scl.compiler.elaboration.expressions.Variable;
-import org.simantics.scl.compiler.elaboration.expressions.VariableProcedure;
 import org.simantics.scl.compiler.internal.parsing.Symbol;
 import org.simantics.scl.compiler.types.Type;
 
@@ -20,7 +19,6 @@ public abstract class Equation extends Symbol {
     public abstract void collectFreeVariables(THashSet<Variable> vars);
     public abstract void collectEffects(THashSet<Type> effects);
     public abstract void checkType(TypingContext context);
-    public abstract void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs);
     public abstract void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars);
     public abstract void resolve(TranslationContext context);
     public abstract void accept(EquationVisitor visitor);
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ASTExpression.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ASTExpression.java
index 4a65459b8..fa54f8ab2 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ASTExpression.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ASTExpression.java
@@ -25,12 +25,6 @@ public abstract class ASTExpression extends SimplifiableExpression {
         throw new InternalCompilerError(getClass().getSimpleName() + " does not support collectFreeVariables.");
     }
     
-    @Override
-    final public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        throw new InternalCompilerError(getClass().getSimpleName() + " does not support collectRefs.");
-    }
-    
     @Override
     final public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/Case.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/Case.java
index 54be27b3c..c8f0eb893 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/Case.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/Case.java
@@ -35,10 +35,6 @@ public class Case extends Symbol {
         return lhs;
     }
 
-	public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        value.collectRefs(allRefs, refs);
-    }
-
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
         value.collectVars(allVars, vars);
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/DecoratingExpression.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/DecoratingExpression.java
index 9b6c2645c..796a41c69 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/DecoratingExpression.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/DecoratingExpression.java
@@ -26,11 +26,6 @@ public abstract class DecoratingExpression extends SimplifiableExpression {
         super(loc);
         this.expression = expression;
     }
-
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        expression.collectRefs(allRefs, refs);
-    }
     
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EAmbiguous.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EAmbiguous.java
index 73c4fa3a0..2b5c813a1 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EAmbiguous.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EAmbiguous.java
@@ -42,11 +42,6 @@ public class EAmbiguous extends SimplifiableExpression {
         this.activeCount = alternatives.length;
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EApply.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EApply.java
index 375039e0b..4065f463a 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EApply.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EApply.java
@@ -76,13 +76,6 @@ public class EApply extends Expression {
         return parameters;
     }
     
-
-    public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        function.collectRefs(allRefs, refs);
-        for(Expression parameter : parameters)
-            parameter.collectRefs(allRefs, refs);
-    }
-    
     public void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars) {
         function.collectVars(allVars, vars);
         for(Expression parameter : parameters)
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EApplyType.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EApplyType.java
index cd54a44d6..f441a1be5 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EApplyType.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EApplyType.java
@@ -50,21 +50,17 @@ public class EApplyType extends Expression {
         return parameter;
     }
 
-	public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        expression.collectRefs(allRefs, refs);
+    public void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars) {
+        expression.collectVars(allVars, vars);
     }
-	
-	public void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars) {
-	    expression.collectVars(allVars, vars);
-	}
 
-	@Override
-	protected void updateType() throws MatchException {
-	    setType(Types.instantiate(expression.getType(), parameter));
-	}
-	
-	@Override
-	public IVal toVal(CompilationContext context, CodeWriter w) {
+    @Override
+    protected void updateType() throws MatchException {
+        setType(Types.instantiate(expression.getType(), parameter));
+    }
+
+    @Override
+    public IVal toVal(CompilationContext context, CodeWriter w) {
         IVal val = expression.toVal(context, w);
         return val.createSpecialization(parameter);
     }
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EAsPattern.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EAsPattern.java
index 1a4a5bbd0..98c54844c 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EAsPattern.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EAsPattern.java
@@ -40,12 +40,6 @@ public class EAsPattern extends Expression {
         return pattern;
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        pattern.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EBind.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EBind.java
index b4d824caa..3bec2aaa1 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EBind.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EBind.java
@@ -43,12 +43,6 @@ public class EBind extends SimplifiableExpression {
         this.value = value;
         this.in = in;
     }
-
-    @Override
-    public void collectRefs(final TObjectIntHashMap<Object> allRefs, final TIntHashSet refs) {
-        value.collectRefs(allRefs, refs);
-        in.collectRefs(allRefs, refs);
-    }
     
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ECHRRuleset.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ECHRRuleset.java
index d23b2e4ce..a8ad1480d 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ECHRRuleset.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ECHRRuleset.java
@@ -26,30 +26,29 @@ public class ECHRRuleset extends Expression {
         this.in = in;
     }
     
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        ruleset.collectRefs(allRefs, refs);
-        in.collectRefs(allRefs, refs);
-    }
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars) {
         ruleset.collectVars(allVars, vars);
         in.collectVars(allVars, vars);
     }
+
     @Override
     protected void updateType() throws MatchException {
         setType(in.getType());
     }
+
     @Override
     public IVal toVal(CompilationContext context, CodeWriter w) {
         ruleset.generateCode(w);
         return in.toVal(context, w);
     }
+
     @Override
     public void collectFreeVariables(THashSet<Variable> vars) {
         ruleset.collectFreeVariables(vars);
         in.collectFreeVariables(vars);
     }
+
     @Override
     public Expression resolve(TranslationContext context) {
         if(context.currentRuleset != null) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ECHRRulesetConstructor.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ECHRRulesetConstructor.java
index 25ae61345..734fd71b4 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ECHRRulesetConstructor.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ECHRRulesetConstructor.java
@@ -24,27 +24,27 @@ public class ECHRRulesetConstructor extends Expression {
     public ECHRRulesetConstructor(CHRRuleset ruleset) {
         this.ruleset = ruleset;
     }
-    
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        ruleset.collectRefs(allRefs, refs);
-    }
+
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars) {
         ruleset.collectVars(allVars, vars);
     }
+
     @Override
     protected void updateType() throws MatchException {
         throw new InternalCompilerError("Type of ECHRRulesetConstructor should be already given.");
     }
+
     @Override
     public IVal toVal(CompilationContext context, CodeWriter w) {
         return ruleset.generateCode(w);
     }
+
     @Override
     public void collectFreeVariables(THashSet<Variable> vars) {
         ruleset.collectFreeVariables(vars);
     }
+
     @Override
     public Expression resolve(TranslationContext context) {
         context.pushFrame();
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ECHRSelect.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ECHRSelect.java
index 6b4a7fe86..fbaff1200 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ECHRSelect.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ECHRSelect.java
@@ -38,12 +38,6 @@ public class ECHRSelect extends Expression {
         this.query = query;
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        query.collectRefs(allRefs, refs);
-        expression.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars) {
         query.collectVars(allVars, vars);
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EConstant.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EConstant.java
index 037144a4c..4a2e07f43 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EConstant.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EConstant.java
@@ -35,7 +35,7 @@ import gnu.trove.set.hash.THashSet;
 import gnu.trove.set.hash.TIntHashSet;
 
 public class EConstant extends Expression {
-    SCLValue value;
+    public SCLValue value;
     Type[] typeParameters;
     
     public EConstant(SCLValue value, Type ... typeParameters) {
@@ -83,23 +83,17 @@ public class EConstant extends Expression {
         return this;
     }
 
-	public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        int id = allRefs.get(value);
-        if(id >= 0)
-            refs.add(id);
+    @Override
+    public void collectVars(TObjectIntHashMap<Variable> allVars,
+            TIntHashSet vars) {   
     }
-	
-	@Override
-	public void collectVars(TObjectIntHashMap<Variable> allVars,
-	        TIntHashSet vars) {   
-	}
 
-	public void toString(StringBuilder b, TypeUnparsingContext tuc) {
-	    Name name = value.getName();
-	    if(name.module.equals("Builtin") || name.module.equals("Prelude"))
-	        b.append(name.name);
-	    else
-	        b.append(name);
+    public void toString(StringBuilder b, TypeUnparsingContext tuc) {
+        Name name = value.getName();
+        if(name.module.equals("Builtin") || name.module.equals("Prelude"))
+            b.append(name.name);
+        else
+            b.append(name);
         /*for(Type type : typeParameters) {
             b.append(" <");
             b.append(type.toString(tuc));
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EEnforce.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EEnforce.java
index 49d010bce..bfaf699ed 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EEnforce.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EEnforce.java
@@ -29,12 +29,6 @@ public class EEnforce extends SimplifiableExpression {
         return query;
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        query.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EEquations.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EEquations.java
index dd1a7e415..bffb7f026 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EEquations.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EEquations.java
@@ -49,12 +49,6 @@ public class EEquations extends SimplifiableExpression {
         return transformer.transform(this);
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        for(Equation equation : equations)
-            equation.collectRefs(allRefs, refs);        
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars) {
         for(Equation equation : equations)
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EError.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EError.java
index c7ea89b30..b3f4f6488 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EError.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EError.java
@@ -24,28 +24,25 @@ public class EError extends Expression {
         setType(type);
     }
     
-    public EError() {     
+    public EError() {
     }
     
     public EError(long loc) {
         this(loc, Types.metaVar(Kinds.STAR));
     }
 
-	public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
+    @Override
+    public void collectVars(TObjectIntHashMap<Variable> allVars,
+            TIntHashSet vars) {
     }
-	
-	@Override
-	public void collectVars(TObjectIntHashMap<Variable> allVars,
-	        TIntHashSet vars) {    
-	}
 
-	@Override
-	protected void updateType() throws MatchException {
-	    setType(Types.metaVar(Kinds.STAR));	    
-	}
-	
-	@Override
-	public IVal toVal(CompilationContext context, CodeWriter w) {
+    @Override
+    protected void updateType() throws MatchException {
+        setType(Types.metaVar(Kinds.STAR));
+    }
+
+    @Override
+    public IVal toVal(CompilationContext context, CodeWriter w) {
         throw new UnsupportedOperationException();
     }
 
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EExternalConstant.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EExternalConstant.java
index 611e96d36..0b5678f99 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EExternalConstant.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EExternalConstant.java
@@ -35,27 +35,24 @@ public class EExternalConstant extends Expression {
         return value;
     }
 
-	public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
+    @Override
+    public void collectVars(TObjectIntHashMap<Variable> allVars,
+            TIntHashSet vars) {	    
     }
 
-	@Override
-	public void collectVars(TObjectIntHashMap<Variable> allVars,
-	        TIntHashSet vars) {	    
-	}
-	
-	public void toString(StringBuilder b, TypeUnparsingContext tuc) {
+    public void toString(StringBuilder b, TypeUnparsingContext tuc) {
         b.append(value);
     }
 
-	@Override
-	protected void updateType() throws MatchException {
-	    throw new InternalCompilerError("EExternalConstants must have explicitly defined type.");
-	}
-	
-	@Override
-	public IVal toVal(CompilationContext context, CodeWriter w) {
-		ModuleWriter mw = w.getModuleWriter();
-		return mw.getExternalConstant(value, getType());
+    @Override
+    protected void updateType() throws MatchException {
+        throw new InternalCompilerError("EExternalConstants must have explicitly defined type.");
+    }
+
+    @Override
+    public IVal toVal(CompilationContext context, CodeWriter w) {
+        ModuleWriter mw = w.getModuleWriter();
+        return mw.getExternalConstant(value, getType());
     }
 
     @Override
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EFieldAccess.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EFieldAccess.java
index 0bc8a4317..0a4d0ee16 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EFieldAccess.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EFieldAccess.java
@@ -35,13 +35,6 @@ public class EFieldAccess extends SimplifiableExpression {
         	((EFieldAccess)parent).lastAccessor = false;
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        parent.collectRefs(allRefs, refs);
-        accessor.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EGetConstraint.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EGetConstraint.java
index 5f9a1eb59..8534f4624 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EGetConstraint.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EGetConstraint.java
@@ -20,11 +20,6 @@ public class EGetConstraint extends SimplifiableExpression {
         super(loc);
         this.constraint = constraint;
     }
-
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-    }
     
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EIf.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EIf.java
index 418ba69c9..ea64ac034 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EIf.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EIf.java
@@ -39,29 +39,22 @@ public class EIf extends Expression {
         this.else_ = else_;
     }
 
-	public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        condition.collectRefs(allRefs, refs);
-        then_.collectRefs(allRefs, refs);
-        if(else_ != null)
-            else_.collectRefs(allRefs, refs);
-    }
-
-	@Override
-	public void collectVars(TObjectIntHashMap<Variable> allVars,
-	        TIntHashSet vars) {
-	    condition.collectVars(allVars, vars);
+    @Override
+    public void collectVars(TObjectIntHashMap<Variable> allVars,
+            TIntHashSet vars) {
+        condition.collectVars(allVars, vars);
         then_.collectVars(allVars, vars);
         if(else_ != null)
             else_.collectVars(allVars, vars);
-	}
+    }
 
-	@Override
-	protected void updateType() throws MatchException {
-	    setType(then_.getType());
-	}
-	
-	@Override
-	public IVal toVal(CompilationContext context, CodeWriter w) {
+    @Override
+    protected void updateType() throws MatchException {
+        setType(then_.getType());
+    }
+
+    @Override
+    public IVal toVal(CompilationContext context, CodeWriter w) {
         IVal conditionVal = condition.toVal(context, w); 
         CodeWriter joinPoint = w.createBlock(getType());
         CodeWriter thenBlock = w.createBlock();
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EIntegerLiteral.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EIntegerLiteral.java
index 0b5d1a16d..856dcd371 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EIntegerLiteral.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EIntegerLiteral.java
@@ -28,11 +28,6 @@ public class EIntegerLiteral extends SimplifiableExpression {
         this.value = value;
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ELambda.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ELambda.java
index 5138ec596..51b1f909e 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ELambda.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ELambda.java
@@ -37,20 +37,15 @@ public class ELambda extends SimplifiableExpression {
         this(loc, new Case(new Expression[] {pat}, exp));
     }
 
-	public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
+    @Override
+    public void collectVars(TObjectIntHashMap<Variable> allVars,
+            TIntHashSet vars) {
         for(Case case_ : cases)
-            case_.collectRefs(allRefs, refs);
-    }
-	
-	@Override
-	public void collectVars(TObjectIntHashMap<Variable> allVars,
-	        TIntHashSet vars) {
-	    for(Case case_ : cases)
             case_.collectVars(allVars, vars);
-	}
+    }
 
-	public Expression decomposeMatching() {
-	    Expression[] patterns = cases[0].patterns;
+    public Expression decomposeMatching() {
+        Expression[] patterns = cases[0].patterns;
         int arity = patterns.length;
         
         // Simple cases
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ELambdaType.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ELambdaType.java
index d413b8c35..b06f7b770 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ELambdaType.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ELambdaType.java
@@ -30,22 +30,18 @@ public class ELambdaType extends Expression {
         this.value = value;
     }
 
-	public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        value.collectRefs(allRefs, refs);
+    @Override
+    public void collectVars(TObjectIntHashMap<Variable> allVars,
+            TIntHashSet vars) {
+        value.collectVars(allVars, vars);
     }
-	
-	@Override
-	public void collectVars(TObjectIntHashMap<Variable> allVars,
-	        TIntHashSet vars) {
-	    value.collectVars(allVars, vars);
-	}
-	
-	@Override
-	protected void updateType() throws MatchException {
-	    setType(Types.forAll(parameters, value.getType()));
-	}
 
-	@Override
+    @Override
+    protected void updateType() throws MatchException {
+        setType(Types.forAll(parameters, value.getType()));
+    }
+
+    @Override
     public IVal toVal(CompilationContext context, CodeWriter w) {
         return lambdaToVal(context, w);
     }
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ELet.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ELet.java
index 5bde43500..7b7338a78 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ELet.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ELet.java
@@ -36,13 +36,6 @@ public class ELet extends Expression {
         this.assignments = assignments;
         this.in = in;
     }
-
-    @Override
-    public void collectRefs(final TObjectIntHashMap<Object> allRefs, final TIntHashSet refs) {
-        for(Assignment assign : assignments)
-            assign.value.collectRefs(allRefs, refs);
-        in.collectRefs(allRefs, refs);
-    }
     
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EListComprehension.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EListComprehension.java
index fa21346f1..a06100dd7 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EListComprehension.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EListComprehension.java
@@ -31,13 +31,6 @@ public class EListComprehension extends SimplifiableExpression {
         this.qualifier = qualifier;
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        head.collectRefs(allRefs, refs);
-        qualifier.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EListLiteral.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EListLiteral.java
index 5c2a0d9d4..d2a1d3509 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EListLiteral.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EListLiteral.java
@@ -36,13 +36,6 @@ public class EListLiteral extends SimplifiableExpression {
     public Expression[] getComponents() {
         return components;
     }
-    
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        for(Expression component : components)
-            component.collectRefs(allRefs, refs);
-    }
 
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ELiteral.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ELiteral.java
index d2a671a1d..14bd02344 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ELiteral.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ELiteral.java
@@ -39,25 +39,22 @@ public class ELiteral extends Expression {
         return value;
     }
 
-	public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
+    @Override
+    public void collectVars(TObjectIntHashMap<Variable> allVars,
+            TIntHashSet vars) {	    
     }
 
-	@Override
-	public void collectVars(TObjectIntHashMap<Variable> allVars,
-	        TIntHashSet vars) {	    
-	}
-	
-	public void toString(StringBuilder b, TypeUnparsingContext tuc) {
+    public void toString(StringBuilder b, TypeUnparsingContext tuc) {
         b.append(value);
     }
-	
-	@Override
-	protected void updateType() throws MatchException {
-	    setType(value.getType());	    
-	}
 
-	@Override
-	public IVal toVal(CompilationContext context, CodeWriter w) {
+    @Override
+    protected void updateType() throws MatchException {
+        setType(value.getType());	    
+    }
+
+    @Override
+    public IVal toVal(CompilationContext context, CodeWriter w) {
         return value;
     }
 
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EMatch.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EMatch.java
index 4ad8135c4..0ca1d5442 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EMatch.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EMatch.java
@@ -41,43 +41,36 @@ public class EMatch extends Expression {
         this.cases = cases;
     }
 
-	public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
+    @Override
+    public void collectVars(TObjectIntHashMap<Variable> allVars,
+            TIntHashSet vars) {
         for(Expression s : scrutinee)
-            s.collectRefs(allRefs, refs);
-        for(Case case_ : cases)
-            case_.collectRefs(allRefs, refs);
-    }
-	
-	@Override
-	public void collectVars(TObjectIntHashMap<Variable> allVars,
-	        TIntHashSet vars) {
-	    for(Expression s : scrutinee)
             s.collectVars(allVars, vars);
-	    for(Case case_ : cases)
+        for(Case case_ : cases)
             case_.collectVars(allVars, vars);
-	}
-	
-	@Override
-	protected void updateType() {
-	    setType(cases[0].value.getType());
-	}
+    }
+
+    @Override
+    protected void updateType() {
+        setType(cases[0].value.getType());
+    }
+
+    @Override
+    public IVal toVal(CompilationContext context, CodeWriter w) {
+        ArrayList<Row> rows = new ArrayList<Row>(cases.length);
+        for(Case case_ : cases)
+            rows.add(new Row(case_.patterns, case_.value));
+
+        IVal[] scrutineeVals = new IVal[scrutinee.length];
+        for(int i=0;i<scrutinee.length;++i)
+            scrutineeVals[i] = scrutinee[i].toVal(context, w);
 
-	@Override
-	public IVal toVal(CompilationContext context, CodeWriter w) {
-	    ArrayList<Row> rows = new ArrayList<Row>(cases.length);
-	    for(Case case_ : cases)
-	        rows.add(new Row(case_.patterns, case_.value));
-	    
-	    IVal[] scrutineeVals = new IVal[scrutinee.length];
-	    for(int i=0;i<scrutinee.length;++i)
-	        scrutineeVals[i] = scrutinee[i].toVal(context, w);
-	    
-	    CodeWriter joinPoint = w.createBlock(getType());
-	    CodeWriter failurePoint = w.createBlock(); // TODO generate only one failurePoint per function
-	    PatternMatchingCompiler.split(w, context, scrutineeVals, joinPoint.getContinuation(), failurePoint.getContinuation(), rows);
-	    failurePoint.throw_(location, Throw.MatchingException, "Matching failure at: " + toString());
-	    w.continueAs(joinPoint);
-	    return w.getParameters()[0];
+        CodeWriter joinPoint = w.createBlock(getType());
+        CodeWriter failurePoint = w.createBlock(); // TODO generate only one failurePoint per function
+        PatternMatchingCompiler.split(w, context, scrutineeVals, joinPoint.getContinuation(), failurePoint.getContinuation(), rows);
+        failurePoint.throw_(location, Throw.MatchingException, "Matching failure at: " + toString());
+        w.continueAs(joinPoint);
+        return w.getParameters()[0];
     }
 
     @Override
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ERealLiteral.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ERealLiteral.java
index 9468342bb..5f274dadd 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ERealLiteral.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ERealLiteral.java
@@ -27,11 +27,6 @@ public class ERealLiteral extends SimplifiableExpression {
         this.value = value;
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ERuleset.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ERuleset.java
index 41d43dd06..1a133b6f9 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ERuleset.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ERuleset.java
@@ -141,18 +141,7 @@ public class ERuleset extends SimplifiableExpression {
         }
         in.collectFreeVariables(vars);
     }
-    
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        for(DatalogRule rule : rules) {
-            for(Expression parameter : rule.headParameters)
-                parameter.collectRefs(allRefs, refs);
-            rule.body.collectRefs(allRefs, refs);
-        }
-        in.collectRefs(allRefs, refs);
-    }
-    
+
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
@@ -163,7 +152,7 @@ public class ERuleset extends SimplifiableExpression {
         }
         in.collectVars(allVars, vars);
     }
-    
+
     @Override
     public void collectEffects(THashSet<Type> effects) {
         throw new InternalCompilerError(location, getClass().getSimpleName() + " does not support collectEffects.");
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ESelect.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ESelect.java
index 42fdc6f10..ce4d66bd7 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ESelect.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ESelect.java
@@ -45,13 +45,6 @@ public class ESelect extends SimplifiableExpression {
         this.query = query;
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        expression.collectRefs(allRefs, refs);
-        query.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ESimpleLambda.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ESimpleLambda.java
index 0038dbf38..8f59b3b44 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ESimpleLambda.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ESimpleLambda.java
@@ -55,17 +55,13 @@ public class ESimpleLambda extends Expression {
         this.effect = effect;
     }
 
-	public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        value.collectRefs(allRefs, refs);
+    @Override
+    public void collectVars(TObjectIntHashMap<Variable> allVars,
+            TIntHashSet vars) {
+        value.collectVars(allVars, vars);
     }
-	
-	@Override
-	public void collectVars(TObjectIntHashMap<Variable> allVars,
-	        TIntHashSet vars) {
-	    value.collectVars(allVars, vars);
-	}
 
-	public Expression decomposeMatching() {
+    public Expression decomposeMatching() {
         value = value.decomposeMatching();
         return this;
     }
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ESimpleLet.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ESimpleLet.java
index 1a084b366..422bbea11 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ESimpleLet.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ESimpleLet.java
@@ -45,28 +45,23 @@ public class ESimpleLet extends Expression {
         this.in = in;
     }
 
-	public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        value.collectRefs(allRefs, refs);
-        in.collectRefs(allRefs, refs);
+    @Override
+    public void collectVars(TObjectIntHashMap<Variable> allVars,
+            TIntHashSet vars) {
+        value.collectVars(allVars, vars);
+        in.collectVars(allVars, vars);
     }
-	
-	@Override
-	public void collectVars(TObjectIntHashMap<Variable> allVars,
-	        TIntHashSet vars) {
-	    value.collectVars(allVars, vars);
-	    in.collectVars(allVars, vars);
-	}
 
     @Override
     protected void updateType() throws MatchException {
         setType(in.getType());
     }
-    
-	@Override
-	public IVal toVal(CompilationContext context, CodeWriter w) {
-	    IVal valueVal = value.toVal(context, w);
-	    if(variable != null)
-	        variable.setVal(valueVal);
+
+    @Override
+    public IVal toVal(CompilationContext context, CodeWriter w) {
+        IVal valueVal = value.toVal(context, w);
+        if(variable != null)
+            variable.setVal(valueVal);
         return in.toVal(context, w);
     }
 
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ETransformation.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ETransformation.java
index 3e8f61b03..346e46cd3 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ETransformation.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ETransformation.java
@@ -30,17 +30,6 @@ public class ETransformation extends SimplifiableExpression {
         this.seed = seed;
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        {
-            int ref = allRefs.get(TRANSFORMATION_RULES_TYPECHECKED);
-            if(ref >= 0)
-                refs.add(ref);
-        }
-        seed.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ETypeAnnotation.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ETypeAnnotation.java
index 6452812fc..10c8e6f7a 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ETypeAnnotation.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/ETypeAnnotation.java
@@ -28,20 +28,16 @@ public class ETypeAnnotation extends SimplifiableExpression {
         this.type = type;
     }
 
-	public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        value.collectRefs(allRefs, refs);
+    @Override
+    public void collectVars(TObjectIntHashMap<Variable> allVars,
+            TIntHashSet vars) {
+        value.collectVars(allVars, vars);
     }
-	
-	@Override
-	public void collectVars(TObjectIntHashMap<Variable> allVars,
-	        TIntHashSet vars) {
-	    value.collectVars(allVars, vars);
-	}
 
-	@Override
-	protected void updateType() throws MatchException {
-	    setType(type);
-	}
+    @Override
+    protected void updateType() throws MatchException {
+        setType(type);
+    }
 
     @Override
     public void collectFreeVariables(THashSet<Variable> vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EVariable.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EVariable.java
index 669867ff6..44c03a2ac 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EVariable.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EVariable.java
@@ -46,18 +46,15 @@ public class EVariable extends Expression {
         this.variable = variable;
     }
 
-	public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
+    @Override
+    public void collectVars(TObjectIntHashMap<Variable> allVars,
+            TIntHashSet vars) {
+        int id = allVars.get(variable);
+        if(id >= 0)
+            vars.add(id);
     }
-	
-	@Override
-	public void collectVars(TObjectIntHashMap<Variable> allVars,
-	        TIntHashSet vars) {
-	    int id = allVars.get(variable);
-	    if(id >= 0)
-	        vars.add(id);
-	}
 
-	public void toString(StringBuilder b, TypeUnparsingContext tuc) {
+    public void toString(StringBuilder b, TypeUnparsingContext tuc) {
         b.append(variable == null ? "???" : variable.toString());
     }
 
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EViewPattern.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EViewPattern.java
index 2561e63b9..a2a0a02c5 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EViewPattern.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EViewPattern.java
@@ -26,12 +26,6 @@ public class EViewPattern extends Expression {
         this.pattern = pattern;
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        expression.collectRefs(allRefs, refs);
-        pattern.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars) {
         expression.collectVars(allVars, vars);
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EWhen.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EWhen.java
index 9cdb6eab2..a9fd0367b 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EWhen.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/EWhen.java
@@ -43,13 +43,6 @@ public class EWhen extends SimplifiableExpression {
         this.variables = variables;
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        query.collectRefs(allRefs, refs);
-        action.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/Expression.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/Expression.java
index da3afdbfa..221bc8067 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/Expression.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/Expression.java
@@ -14,6 +14,7 @@ import org.simantics.scl.compiler.elaboration.errors.NotPatternException;
 import org.simantics.scl.compiler.elaboration.expressions.lhstype.LhsType;
 import org.simantics.scl.compiler.elaboration.expressions.lhstype.PatternMatchingLhs;
 import org.simantics.scl.compiler.elaboration.expressions.printing.ExpressionToStringVisitor;
+import org.simantics.scl.compiler.elaboration.expressions.visitors.CollectRefsVisitor;
 import org.simantics.scl.compiler.elaboration.expressions.visitors.ForVariablesUsesVisitor;
 import org.simantics.scl.compiler.elaboration.query.QAtom;
 import org.simantics.scl.compiler.elaboration.relations.SCLRelation;
@@ -103,23 +104,23 @@ public abstract class Expression extends Symbol implements Typed {
             expression = new ESimpleLet(location, null, expression, new ELiteral(NoRepConstant.PUNIT));
         return expression;
     }
-	
-	/**
-	 * Checks the type of the expression against the given type. Adds type
-	 * applications and lambdas if needed.
-	 */
-	public final Expression checkType(TypingContext context, Type requiredType) {
-	    //System.out.println("checkType: " + this + " :: " + requiredType);
-	    if(!context.isInPattern()) {
-	        requiredType = Types.canonical(requiredType);
-    	    if(requiredType instanceof TForAll) {
+
+    /**
+     * Checks the type of the expression against the given type. Adds type
+     * applications and lambdas if needed.
+     */
+    public final Expression checkType(TypingContext context, Type requiredType) {
+        //System.out.println("checkType: " + this + " :: " + requiredType);
+        if(!context.isInPattern()) {
+            requiredType = Types.canonical(requiredType);
+            if(requiredType instanceof TForAll) {
                 TForAll forAll = (TForAll)requiredType;
                 TVar var = forAll.var;
                 TVar newVar = Types.var(var.getKind());
                 requiredType = Types.canonical(forAll.type).replace(var, newVar);
                 return new ELambdaType(new TVar[] {newVar}, checkType(context, requiredType));
             }
-    	    while(requiredType instanceof TFun) {
+            while(requiredType instanceof TFun) {
                 TFun fun = (TFun)requiredType;
                 if(fun.domain instanceof TPred) { // No need to canonicalize
                     ArrayList<Variable> constraints = new ArrayList<Variable>(2);
@@ -143,7 +144,7 @@ public abstract class Expression extends Symbol implements Typed {
                     context.pushEffectUpperBound(location, fun.effect);
                     Expression expr = checkType(context, fun.range);
                     context.popEffectUpperBound();       
-                    
+
                     // Wrap
                     Variable var = new Variable("punit", Types.PUNIT);
                     return new ESimpleLambda(location, var, fun.effect, expr);
@@ -151,14 +152,17 @@ public abstract class Expression extends Symbol implements Typed {
                 else
                     break;
             }
-	    }
-	    return checkBasicType(context, requiredType); 
-	}
+        }
+        return checkBasicType(context, requiredType); 
+    }
+
+    public final void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
+        accept(new CollectRefsVisitor(allRefs, refs));
+    }
 
-	public abstract void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs);
-	public abstract void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars);
+    public abstract void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars);
 
-    public void forVariableUses(VariableProcedure procedure) {
+    public final void forVariableUses(VariableProcedure procedure) {
         accept(new ForVariablesUsesVisitor(procedure));
     }
 
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/GuardedExpressionGroup.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/GuardedExpressionGroup.java
index 07fbc50a6..1e2cd05c4 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/GuardedExpressionGroup.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/GuardedExpressionGroup.java
@@ -25,16 +25,6 @@ public class GuardedExpressionGroup extends Expression {
         this.expressions = expressions;
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        for(GuardedExpression expression : expressions) {
-            for(Expression guard : expression.guards)
-                guard.collectRefs(allRefs, refs);
-            expression.value.collectRefs(allRefs, refs);
-        }
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/accessor/ExpressionAccessor.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/accessor/ExpressionAccessor.java
index e4cdd0937..12c9a9170 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/accessor/ExpressionAccessor.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/accessor/ExpressionAccessor.java
@@ -25,12 +25,6 @@ public class ExpressionAccessor extends FieldAccessor {
         fieldName.collectFreeVariables(vars);
     }
     
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        fieldName.collectRefs(allRefs, refs);
-    }
-    
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/accessor/FieldAccessor.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/accessor/FieldAccessor.java
index aaf80610a..21c892ce4 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/accessor/FieldAccessor.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/accessor/FieldAccessor.java
@@ -18,10 +18,6 @@ public abstract class FieldAccessor extends Symbol {
         this.accessSeparator = accessSeparator;
     }
 
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-    }
-
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
     }
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListAssignment.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListAssignment.java
index a0073b889..1283cc059 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListAssignment.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListAssignment.java
@@ -29,12 +29,6 @@ public class ListAssignment extends ListQualifier {
         pattern.checkTypeAsPattern(context, value.getType());
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        value.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListGenerator.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListGenerator.java
index c7f89ba76..db12689c8 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListGenerator.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListGenerator.java
@@ -33,12 +33,6 @@ public class ListGenerator extends ListQualifier {
         pattern.checkTypeAsPattern(context, componentType);
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        value.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListGuard.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListGuard.java
index c9e29ca5b..2fe49150f 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListGuard.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListGuard.java
@@ -25,12 +25,6 @@ public class ListGuard extends ListQualifier {
         condition.checkType(context, Types.BOOLEAN);
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        condition.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListQualifier.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListQualifier.java
index 048b525f7..47c9cf6d8 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListQualifier.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListQualifier.java
@@ -14,7 +14,6 @@ import gnu.trove.set.hash.TIntHashSet;
 public abstract class ListQualifier extends Symbol {
 
     public abstract void checkType(TypingContext context);
-    public abstract void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs);
     public abstract void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars);
     public abstract void collectFreeVariables(THashSet<Variable> vars);
     /**
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListSeq.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListSeq.java
index 5d633d8d0..a802a80ac 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListSeq.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListSeq.java
@@ -26,13 +26,6 @@ public class ListSeq extends ListQualifier {
         a.checkType(context);
         b.checkType(context);  
     }
-    
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        a.collectRefs(allRefs, refs);
-        b.collectRefs(allRefs, refs);
-    }
 
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListThen.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListThen.java
index 451493ba3..e1061564f 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListThen.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/list/ListThen.java
@@ -47,15 +47,6 @@ public class ListThen extends ListQualifier {
         }
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        left.collectRefs(allRefs, refs);
-        transformer.collectRefs(allRefs, refs);
-        if(by != null)
-            by.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/visitors/CollectRefsVisitor.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/visitors/CollectRefsVisitor.java
new file mode 100644
index 000000000..366dc514b
--- /dev/null
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/expressions/visitors/CollectRefsVisitor.java
@@ -0,0 +1,56 @@
+package org.simantics.scl.compiler.elaboration.expressions.visitors;
+
+import org.simantics.scl.compiler.elaboration.expressions.EConstant;
+import org.simantics.scl.compiler.elaboration.expressions.ETransformation;
+import org.simantics.scl.compiler.elaboration.expressions.StandardExpressionVisitor;
+import org.simantics.scl.compiler.elaboration.query.QAtom;
+import org.simantics.scl.compiler.elaboration.relations.CompositeRelation;
+import org.simantics.scl.compiler.elaboration.relations.SCLRelation;
+
+import gnu.trove.map.hash.TObjectIntHashMap;
+import gnu.trove.set.hash.TIntHashSet;
+
+public class CollectRefsVisitor extends StandardExpressionVisitor {
+    private final TObjectIntHashMap<Object> allRefs;
+    private final TIntHashSet refs;
+    
+    public CollectRefsVisitor(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
+        this.allRefs = allRefs;
+        this.refs = refs;
+    }
+    
+    @Override
+    public void visit(ETransformation expression) {
+        {
+            int ref = allRefs.get(ETransformation.TRANSFORMATION_RULES_TYPECHECKED);
+            if(ref >= 0)
+                refs.add(ref);
+        }
+        super.visit(expression);
+    }
+    
+    @Override
+    public void visit(EConstant expression) {
+        int id = allRefs.get(expression.value);
+        if(id >= 0)
+            refs.add(id);
+    }
+    
+    @Override
+    public void visit(QAtom query) {
+        collectRelationRefs(query.relation);
+        super.visit(query);
+    }
+    
+    private void collectRelationRefs(SCLRelation relation) {
+        if(relation instanceof CompositeRelation) {
+            for(SCLRelation subrelation : ((CompositeRelation) relation).getSubrelations())
+                collectRelationRefs(subrelation);
+        }
+        else {
+            int id = allRefs.get(relation);
+            if(id >= 0)
+                refs.add(id);
+        }
+    }
+}
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QAbstractCombiner.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QAbstractCombiner.java
index 52a59585f..459711a8d 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QAbstractCombiner.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QAbstractCombiner.java
@@ -74,12 +74,6 @@ public abstract class QAbstractCombiner extends Query {
             query.checkType(context);
     }
     
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        for(Query query : queries)
-            query.collectRefs(allRefs, refs);
-    }
-    
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars) {
         for(Query query : queries)
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QAbstractModifier.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QAbstractModifier.java
index 2b6c67711..421bf833e 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QAbstractModifier.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QAbstractModifier.java
@@ -31,12 +31,6 @@ public abstract class QAbstractModifier extends Query {
         query.checkType(context);
     }
     
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        query.collectRefs(allRefs, refs);
-    }
-    
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QAtom.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QAtom.java
index 7a20ae3c5..c988aed56 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QAtom.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QAtom.java
@@ -147,27 +147,6 @@ public class QAtom extends Query {
         }
     }
 
-    private static void collectRefs(SCLRelation relation, TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        if(relation instanceof CompositeRelation) {
-            for(SCLRelation subrelation : ((CompositeRelation) relation).getSubrelations())
-                collectRefs(subrelation, allRefs, refs);
-        }
-        else {
-            int id = allRefs.get(relation);
-            if(id >= 0)
-                refs.add(id);
-        }
-    }
-
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        collectRefs(relation, allRefs, refs);
-        for(Expression parameter : parameters)
-            parameter.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QIf.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QIf.java
index 719f474b6..d148339a4 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QIf.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QIf.java
@@ -32,13 +32,6 @@ public class QIf extends Query {
         elseQuery.collectFreeVariables(vars);
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
-        condition.collectRefs(allRefs, refs);
-        thenQuery.collectRefs(allRefs, refs);
-        elseQuery.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars) {
         condition.collectVars(allVars, vars);
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QMapping.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QMapping.java
index 12da9da3b..08d72563e 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QMapping.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/QMapping.java
@@ -31,13 +31,6 @@ public class QMapping extends Query {
             parameter.collectFreeVariables(vars);
     }
 
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        for(Expression parameter : parameters)
-            parameter.collectRefs(allRefs, refs);
-    }
-
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/Query.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/Query.java
index 0b804caf3..7b610756a 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/Query.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/Query.java
@@ -14,6 +14,7 @@ import org.simantics.scl.compiler.elaboration.expressions.StandardExpressionVisi
 import org.simantics.scl.compiler.elaboration.expressions.Variable;
 import org.simantics.scl.compiler.elaboration.expressions.VariableProcedure;
 import org.simantics.scl.compiler.elaboration.expressions.printing.ExpressionToStringVisitor;
+import org.simantics.scl.compiler.elaboration.expressions.visitors.CollectRefsVisitor;
 import org.simantics.scl.compiler.elaboration.expressions.visitors.ForVariablesUsesVisitor;
 import org.simantics.scl.compiler.elaboration.query.compilation.ConstraintCollectionContext;
 import org.simantics.scl.compiler.elaboration.query.compilation.DerivateException;
@@ -37,7 +38,6 @@ public abstract class Query extends Symbol {
     public static final Query[] EMPTY_ARRAY = new Query[0];
     
     public abstract void collectFreeVariables(THashSet<Variable> vars);
-    public abstract void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs);
     public abstract void collectVars(TObjectIntHashMap<Variable> allVars, TIntHashSet vars);
     public abstract void checkType(TypingContext context);
     
@@ -159,4 +159,7 @@ public abstract class Query extends Symbol {
     public void forVariables(VariableProcedure procedure) {
         accept(new ForVariablesUsesVisitor(procedure));
     }
+    public void collectRefs(TObjectIntHashMap<Object> allRefs, TIntHashSet refs) {
+        accept(new CollectRefsVisitor(allRefs, refs));
+    }
 }
diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/pre/PreQuery.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/pre/PreQuery.java
index dc398f857..859690ec8 100644
--- a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/pre/PreQuery.java
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/query/pre/PreQuery.java
@@ -40,12 +40,6 @@ public abstract class PreQuery extends Query {
         throw new InternalCompilerError(location, getClass().getSimpleName() + " does not support collectConstraints.");
     }
     
-    @Override
-    public void collectRefs(TObjectIntHashMap<Object> allRefs,
-            TIntHashSet refs) {
-        throw new InternalCompilerError(location, getClass().getSimpleName() + " does not support collectRefs.");
-    }
-    
     @Override
     public void collectVars(TObjectIntHashMap<Variable> allVars,
             TIntHashSet vars) {