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diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/translation/CHRTranslation.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/translation/CHRTranslation.java
new file mode 100644
index 000000000..14106711d
--- /dev/null
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/elaboration/chr/translation/CHRTranslation.java
@@ -0,0 +1,142 @@
+package org.simantics.scl.compiler.elaboration.chr.translation;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+
+import org.simantics.scl.compiler.elaboration.chr.CHRLiteral;
+import org.simantics.scl.compiler.elaboration.chr.CHRQuery;
+import org.simantics.scl.compiler.elaboration.chr.CHRRule;
+import org.simantics.scl.compiler.elaboration.chr.relations.CHRConstraint;
+import org.simantics.scl.compiler.elaboration.chr.relations.SpecialCHRRelation;
+import org.simantics.scl.compiler.elaboration.chr.relations.UnresolvedCHRRelation;
+import org.simantics.scl.compiler.elaboration.contexts.TranslationContext;
+import org.simantics.scl.compiler.elaboration.expressions.EApply;
+import org.simantics.scl.compiler.elaboration.expressions.EBinary;
+import org.simantics.scl.compiler.elaboration.expressions.EVar;
+import org.simantics.scl.compiler.elaboration.expressions.Expression;
+import org.simantics.scl.compiler.elaboration.expressions.block.CHRStatement;
+import org.simantics.scl.compiler.elaboration.expressions.block.ConstraintStatement;
+import org.simantics.scl.compiler.elaboration.expressions.list.ListAssignment;
+import org.simantics.scl.compiler.elaboration.expressions.list.ListGenerator;
+import org.simantics.scl.compiler.elaboration.expressions.list.ListGuard;
+import org.simantics.scl.compiler.elaboration.expressions.list.ListQualifier;
+import org.simantics.scl.compiler.environment.AmbiguousNameException;
+import org.simantics.scl.compiler.environment.Environments;
+import org.simantics.scl.compiler.errors.Locations;
+import org.simantics.scl.compiler.internal.parsing.types.TypeAst;
+
+public class CHRTranslation {
+
+    private static CHRLiteral convertExpression(boolean isHead, Expression expression) {
+        if(isHead)
+            return new CHRLiteral(expression.location, SpecialCHRRelation.CHECK, new Expression[] {expression}, false, false);
+        else
+            return new CHRLiteral(expression.location, SpecialCHRRelation.EXECUTE, new Expression[] {expression}, false, false);
+    }
+
+    private static CHRLiteral convertConstraint(boolean remove, boolean negated, Expression expression) {
+        ArrayList<Expression> parameters = new ArrayList<Expression>(4);
+        while(expression instanceof EApply) {
+            EApply apply = (EApply)expression;
+            for(int i=apply.parameters.length-1;i>=0;--i)
+                parameters.add(apply.parameters[i]);
+            expression = apply.function;
+        }
+        EVar var = (EVar)expression;
+        Expression[] parametersArray = new Expression[parameters.size()];
+        for(int i=0,j=parametersArray.length-1;i<parametersArray.length;++i,--j)
+            parametersArray[i] = parameters.get(j);
+        return new CHRLiteral(expression.location, new UnresolvedCHRRelation(var.location, var.name), parametersArray, remove, negated);
+    }
+    
+    private static CHRLiteral convertListQualifier(TranslationContext context, boolean isHead, ListQualifier qualifier) {
+        if(qualifier instanceof ListGuard) {
+            Expression originalExpression = ((ListGuard)qualifier).condition;
+            if(originalExpression instanceof EVar && ((EVar)originalExpression).name.equals("True"))
+                return null;
+            Expression currentExpression = originalExpression;
+            boolean remove = false;
+            boolean negated = false;
+            if(currentExpression instanceof EBinary) {
+                EBinary binary = (EBinary)currentExpression;
+                if(binary.negation==null || !binary.rights.isEmpty())
+                    return convertExpression(isHead, originalExpression);
+                currentExpression = binary.left;
+                remove = true;
+            }
+            else if(currentExpression instanceof EApply) {
+                EApply apply = (EApply)currentExpression;
+                if(apply.function instanceof EVar && ((EVar)apply.function).name.equals("not")) {
+                    negated = true;
+                    if(apply.parameters.length == 1)
+                        currentExpression = apply.parameters[0];
+                    else {
+                        currentExpression = new EApply(
+                                Locations.combine(apply.parameters[0].location, apply.parameters[apply.parameters.length-1].location),
+                                apply.parameters[0],
+                                Arrays.copyOfRange(apply.parameters, 1, apply.parameters.length));
+                    }
+                }
+            }
+            if(isConstraint(context, currentExpression))
+                return convertConstraint(remove, negated, currentExpression);
+            else
+                return convertExpression(isHead, originalExpression);
+        }
+        else if(qualifier instanceof ListAssignment) {
+            ListAssignment assignment = (ListAssignment)qualifier;
+            return new CHRLiteral(assignment.location, SpecialCHRRelation.EQUALS, new Expression[] {
+                    assignment.pattern, assignment.value 
+            }, false, false);
+        }
+        else if(qualifier instanceof ListGenerator) {
+            ListGenerator generator = (ListGenerator)qualifier;
+            return new CHRLiteral(generator.location, SpecialCHRRelation.MEMBER, new Expression[] {
+                    generator.pattern, generator.value
+            }, false, false);
+        }
+        else {
+            context.getErrorLog().log(qualifier.location, "Invalid CHR literal.");
+            return null;
+        }
+    }
+    
+    private static boolean isConstraint(TranslationContext context, Expression expression) {
+        while(expression instanceof EApply)
+            expression = ((EApply)expression).function;
+        if(!(expression instanceof EVar))
+            return false;
+        String name = ((EVar)expression).name;
+        if(TranslationContext.isConstructorName(name))
+            return true;
+        try {
+            return Environments.getRelation(context.getEnvironment(), name) != null;
+        } catch (AmbiguousNameException e) {
+            return true;
+        }
+    }
+
+    public static CHRRule convertCHRStatement(TranslationContext context, CHRStatement statement) {
+        ArrayList<CHRLiteral> head = new ArrayList<CHRLiteral>(statement.head.length);
+        for(ListQualifier qualifier : statement.head) {
+            CHRLiteral literal = convertListQualifier(context, true, qualifier);
+            if(literal != null)
+                head.add(literal);
+        }
+        ArrayList<CHRLiteral> body = new ArrayList<CHRLiteral>(statement.body.length);
+        for(ListQualifier qualifier : statement.body) {
+            CHRLiteral literal = convertListQualifier(context, false, qualifier);
+            if(literal != null)
+                body.add(literal);
+        }
+        return new CHRRule(statement.location,
+                new CHRQuery(head.toArray(new CHRLiteral[head.size()])),
+                new CHRQuery(body.toArray(new CHRLiteral[body.size()])),
+                null);
+    }
+
+    public static CHRConstraint convertConstraintStatement(TranslationContext context, ConstraintStatement statement) {
+        return new CHRConstraint(statement.location, statement.name.text, TypeAst.toTypes(context, statement.parameterTypes));
+    }
+    
+}