diff --git a/AlgebraicDataflowArchitectureModel/src/generators/JavaCodeGenerator.java b/AlgebraicDataflowArchitectureModel/src/generators/JavaCodeGenerator.java
index 32b9289..a15057e 100644
--- a/AlgebraicDataflowArchitectureModel/src/generators/JavaCodeGenerator.java
+++ b/AlgebraicDataflowArchitectureModel/src/generators/JavaCodeGenerator.java
@@ -1088,11 +1088,7 @@
 		if (res.getInitialValue() != null) {
 			initializer = res.getInitialValue().toImplementation(new String[] {""});
 		} else if (stateType != null) {
-			if (DataConstraintModel.typeList.isAncestorOf(stateType)) {
-				initializer = "new " + res.getResourceStateType().getImplementationTypeName() + "()";
-			} else if (DataConstraintModel.typeMap.isAncestorOf(stateType)) {
-				initializer = "new " + res.getResourceStateType().getImplementationTypeName() + "()";
-			}
+			initializer = DataConstraintModel.getDefaultValue(stateType);
 		}
 		return initializer;
 	}
diff --git a/AlgebraicDataflowArchitectureModel/src/generators/JavaSpecific.java b/AlgebraicDataflowArchitectureModel/src/generators/JavaSpecific.java
index 72d79a9..6134a5f 100644
--- a/AlgebraicDataflowArchitectureModel/src/generators/JavaSpecific.java
+++ b/AlgebraicDataflowArchitectureModel/src/generators/JavaSpecific.java
@@ -106,11 +106,7 @@
 		if (initialValue != null) {
 			initializer = initialValue.toImplementation(new String[] {""});
 		} else if (type != null) {
-			if (DataConstraintModel.typeList.isAncestorOf(type)) {
-				initializer = "new " + type.getImplementationTypeName() + "()";
-			} else if (DataConstraintModel.typeMap.isAncestorOf(type)) {
-				initializer = "new " + type.getImplementationTypeName() + "()";
-			}
+			initializer = DataConstraintModel.getDefaultValue(type);
 		}
 		return initializer;
 	}
diff --git a/AlgebraicDataflowArchitectureModel/src/generators/JerseyCodeGenerator.java b/AlgebraicDataflowArchitectureModel/src/generators/JerseyCodeGenerator.java
index 151ab6e..2d1c1c2 100644
--- a/AlgebraicDataflowArchitectureModel/src/generators/JerseyCodeGenerator.java
+++ b/AlgebraicDataflowArchitectureModel/src/generators/JerseyCodeGenerator.java
@@ -1165,12 +1165,8 @@
 		String initializer = null;
 		if (res.getInitialValue() != null) {
 			initializer = res.getInitialValue().toImplementation(new String[] {""});
-		} else {
-			if (DataConstraintModel.typeList.isAncestorOf(stateType)) {
-				initializer = "new " + res.getResourceStateType().getImplementationTypeName() + "()";
-			} else if (DataConstraintModel.typeMap.isAncestorOf(stateType)) {
-				initializer = "new " + res.getResourceStateType().getImplementationTypeName() + "()";
-			}
+		} else if (stateType != null) {
+			initializer = DataConstraintModel.getDefaultValue(stateType);
 		}
 		return initializer;
 	}
diff --git a/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/DataConstraintModel.java b/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/DataConstraintModel.java
index 903c152..64e1da9 100644
--- a/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/DataConstraintModel.java
+++ b/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/DataConstraintModel.java
@@ -1,1240 +1,1282 @@
-package models.dataConstraintModel;
-
-import java.util.AbstractMap;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Stack;
-
-import models.algebra.Constant;
-import models.algebra.Expression;
-import models.algebra.LambdaAbstraction;
-import models.algebra.Symbol;
-import models.algebra.Term;
-import models.algebra.Type;
-import models.algebra.Variable;
-import parser.Parser;
-
-public class DataConstraintModel {
-	protected List<ResourcePath> resourcePaths = null;
-	protected HashMap<String, ResourceHierarchy> resourceHierarchies = null;
-	protected HashMap<String, Channel> channels = null;
-	protected HashMap<String, Channel> inputChannels = null;
-	protected HashMap<String, Type> types = null;
-	protected HashMap<String, Symbol> symbols = null;
-	public static final Type typeInt = new Type("Int", "int");
-	public static final Type typeLong = new Type("Long", "long", typeInt);
-	public static final Type typeFloat = new Type("Float", "float", typeInt);
-	public static final Type typeDouble = new Type("Double", "double", typeFloat);
-	public static final Type typeBoolean = new Type("Bool", "boolean");
-	public static final Type typeString = new Type("Str", "String") {
-		public String valueToRepresentation(Object value) {
-			if (value instanceof String) {
-				return Parser.DOUBLE_QUOT + (String) value + Parser.DOUBLE_QUOT;
-			}
-			return value.toString();
-		}
-		public Object representationToValue(String representation) {
-			if (representation.startsWith(Parser.DOUBLE_QUOT) && representation.endsWith(Parser.DOUBLE_QUOT)) {
-				return representation.substring(1, representation.length() - 1);
-			}
-			return representation;
-		}
-	};
-	public static final Type typeList = new Type("List", "ArrayList", "List");
-	public static final Type typeListInt = new Type("List", "ArrayList<>", "List<Integer>", typeList);
-	public static final Type typeListStr = new Type("List", "ArrayList<>", "List<String>", typeList);
-	public static final Type typeTuple = new Type("Tuple", "AbstractMap.SimpleEntry", "Map.Entry");
-	public static final Type typePair = new Type("Pair", "Pair", "Pair");
-	public static final Type typePairInt = new Type("Pair", "Pair<Integer>", "Pair<Integer>", typePair);
-	public static final Type typePairStr = new Type("Pair", "Pair<String>", "Pair<String>", typePair);
-	public static final Type typePairDouble = new Type("Pair", "Pair<Double>", "Pair<Double>", typePair);
-	public static final Type typeMap = new Type("Map", "HashMap<>", "Map");
-	public static final JsonType typeJson = new JsonType("Json", "HashMap<>", "Map<String, Object>");
-	public static final Symbol add = new Symbol(Parser.ADD, 2, Symbol.Type.INFIX, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (!(args.get(0).getClass() == Constant.class)) {
-				return null;
-			}
-			if (!(args.get(1).getClass() == Constant.class)) {
-				return null;
-			}
-			Constant arg0 = (Constant) args.get(0);
-			Constant arg1 = (Constant) args.get(1);
-			String sArg0 = arg0.getSymbol().toString();
-			String sArg1 = arg1.getSymbol().toString();
-			if (arg0.getType() != null && arg1.getType() != null) {
-				if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
-					return new Constant(Double.toString(Double.parseDouble(sArg0) + Double.parseDouble(sArg1)), typeDouble);
-				} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
-					return new Constant(Float.toString(Float.parseFloat(sArg0) + Float.parseFloat(sArg1)), typeFloat);
-				} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
-					return new Constant(Long.toString(Long.parseLong(sArg0) + Long.parseLong(sArg1)), typeLong);
-				} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
-					return new Constant(Integer.toString(Integer.parseInt(sArg0) + Integer.parseInt(sArg1)), typeInt);
-				}
-			}
-			if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
-				return new Constant(Double.toString(Double.parseDouble(sArg0) + Double.parseDouble(sArg1)), typeDouble);
-			} else {
-				return new Constant(Integer.toString(Integer.parseInt(sArg0) + Integer.parseInt(sArg1)), typeInt);
-			}
-		}
-	});
-	public static final Symbol mul = new Symbol(Parser.MUL, 2, Symbol.Type.INFIX, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (!(args.get(0).getClass() == Constant.class)) {
-				return null;
-			}
-			if (!(args.get(1).getClass() == Constant.class)) {
-				return null;
-			}
-			Constant arg0 = (Constant) args.get(0);
-			Constant arg1 = (Constant) args.get(1);
-			String sArg0 = arg0.getSymbol().toString();
-			String sArg1 = arg1.getSymbol().toString();
-			if (arg0.getType() != null && arg1.getType() != null) {
-				if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
-					return new Constant(Double.toString(Double.parseDouble(sArg0) * Double.parseDouble(sArg1)), typeDouble);
-				} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
-					return new Constant(Float.toString(Float.parseFloat(sArg0) * Float.parseFloat(sArg1)), typeFloat);
-				} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
-					return new Constant(Long.toString(Long.parseLong(sArg0) * Long.parseLong(sArg1)), typeLong);
-				} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
-					return new Constant(Integer.toString(Integer.parseInt(sArg0) * Integer.parseInt(sArg1)), typeInt);
-				}
-			}
-			if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
-				return new Constant(Double.toString(Double.parseDouble(sArg0) * Double.parseDouble(sArg1)), typeDouble);
-			} else {
-				return new Constant(Integer.toString(Integer.parseInt(sArg0) * Integer.parseInt(sArg1)), typeInt);
-			}
-		}
-	});
-	public static final Symbol sub = new Symbol(Parser.SUB, 2, Symbol.Type.INFIX, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (!(args.get(0).getClass() == Constant.class)) {
-				return null;
-			}
-			if (!(args.get(1).getClass() == Constant.class)) {
-				return null;
-			}
-			Constant arg0 = (Constant) args.get(0);
-			Constant arg1 = (Constant) args.get(1);
-			String sArg0 = arg0.getSymbol().toString();
-			String sArg1 = arg1.getSymbol().toString();
-			if (arg0.getType() != null && arg1.getType() != null) {
-				if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
-					return new Constant(Double.toString(Double.parseDouble(sArg0) - Double.parseDouble(sArg1)), typeDouble);
-				} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
-					return new Constant(Float.toString(Float.parseFloat(sArg0) - Float.parseFloat(sArg1)), typeFloat);
-				} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
-					return new Constant(Long.toString(Long.parseLong(sArg0) - Long.parseLong(sArg1)), typeLong);
-				} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
-					return new Constant(Integer.toString(Integer.parseInt(sArg0) - Integer.parseInt(sArg1)), typeInt);
-				}
-			}
-			if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
-				return new Constant(Double.toString(Double.parseDouble(sArg0) - Double.parseDouble(sArg1)), typeDouble);
-			} else {
-				return new Constant(Integer.toString(Integer.parseInt(sArg0) - Integer.parseInt(sArg1)), typeInt);
-			}
-		}
-	});
-	public static final Symbol div = new Symbol(Parser.DIV, 2, Symbol.Type.INFIX, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (!(args.get(0).getClass() == Constant.class)) {
-				return null;
-			}
-			if (!(args.get(1).getClass() == Constant.class)) {
-				return null;
-			}
-			Constant arg0 = (Constant) args.get(0);
-			Constant arg1 = (Constant) args.get(1);
-			String sArg0 = arg0.getSymbol().toString();
-			String sArg1 = arg1.getSymbol().toString();
-			if (arg0.getType() != null && arg1.getType() != null) {
-				if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
-					return new Constant(Double.toString(Double.parseDouble(sArg0) / Double.parseDouble(sArg1)), typeDouble);
-				} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
-					return new Constant(Float.toString(Float.parseFloat(sArg0) / Float.parseFloat(sArg1)), typeFloat);
-				} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
-					return new Constant(Long.toString(Long.parseLong(sArg0) / Long.parseLong(sArg1)), typeLong);
-				} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
-					return new Constant(Integer.toString(Integer.parseInt(sArg0) / Integer.parseInt(sArg1)), typeInt);
-				}
-			}
-			if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
-				return new Constant(Double.toString(Double.parseDouble(sArg0) / Double.parseDouble(sArg1)), typeDouble);
-			} else {
-				return new Constant(Integer.toString(Integer.parseInt(sArg0) / Integer.parseInt(sArg1)), typeInt);
-			}
-		}
-	});
-	public static final Symbol mod = new Symbol(Parser.MOD, 2, Symbol.Type.INFIX, "%", Symbol.Type.INFIX, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (!(args.get(0).getClass() == Constant.class)) {
-				return null;
-			}
-			if (!(args.get(1).getClass() == Constant.class)) {
-				return null;
-			}
-			Constant arg0 = (Constant) args.get(0);
-			Constant arg1 = (Constant) args.get(1);
-			String sArg0 = arg0.getSymbol().toString();
-			String sArg1 = arg1.getSymbol().toString();
-			if (arg0.getType() != null && arg1.getType() != null) {
-				if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
-					return new Constant(Long.toString(Long.parseLong(sArg0) % Long.parseLong(sArg1)), typeLong);
-				} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
-					return new Constant(Integer.toString(Integer.parseInt(sArg0) % Integer.parseInt(sArg1)), typeInt);
-				}
-			}
-			return new Constant(Integer.toString(Integer.parseInt(sArg0) % Integer.parseInt(sArg1)));
-		}
-	});
-	public static final Symbol minus = new Symbol(Parser.MINUS, 1, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (!(args.get(0).getClass() == Constant.class)) {
-				return null;
-			}
-			Constant arg = (Constant) args.get(0);
-			String sArg = arg.getSymbol().toString();
-			if (arg.getType() != null) {
-				if (arg.getType().equals(typeDouble)) {
-					return new Constant(Double.toString(-Double.parseDouble(sArg)), typeDouble);
-				} else if (arg.getType().equals(typeFloat)) {
-					return new Constant(Float.toString(-Float.parseFloat(sArg)), typeFloat);
-				} else if (arg.getType().equals(typeLong)) {
-					return new Constant(Long.toString(-Long.parseLong(sArg)), typeLong);
-				} else if (arg.getType().equals(typeInt)) {
-					return new Constant(Integer.toString(-Integer.parseInt(sArg)), typeInt);
-				}
-			}
-			if (sArg.contains(Parser.DOT)) {
-				return new Constant(Double.toString(-Double.parseDouble(sArg)), typeDouble);
-			} else {
-				return new Constant(Integer.toString(-Integer.parseInt(sArg)), typeInt);
-			}
-		}
-	});
-	public static final Symbol eq = new Symbol(Parser.EQ, 2, Symbol.Type.INFIX, new Symbol.IImplGenerator() {
-		@Override
-		public String generate(Type type, Type[] childrenTypes, String[] children, String[] childrenSideEffects, String[] sideEffect) {
-			for (String s: childrenSideEffects) {
-				sideEffect[0] += s;
-			}
-			if (childrenTypes[0] != null && childrenTypes[0].equals(typeString) 
-					&& childrenTypes[1] != null && childrenTypes[1].equals(typeString)) {
-				return children[0] + ".equals(" + children[1] + ")";
-			}
-			return "(" + children[0] + "==" + children[1] + ")";
-		}
-	}, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (!(args.get(0).getClass() == Constant.class)) {
-				return null;
-			}
-			if (!(args.get(1).getClass() == Constant.class)) {
-				return null;
-			}
-			Constant arg0 = (Constant) args.get(0);
-			Constant arg1 = (Constant) args.get(1);
-			String sArg0 = arg0.getSymbol().toString();
-			String sArg1 = arg1.getSymbol().toString();
-			boolean result = false;
-			if (arg0.getType() == null || arg1.getType() == null) {
-				if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
-					result = Double.parseDouble(sArg0) == Double.parseDouble(sArg1);
-				} else {
-					result = Integer.parseInt(sArg0) == Integer.parseInt(sArg1);
-				}
-			}
-			if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
-				result = (Double.parseDouble(sArg0) == Double.parseDouble(sArg1));
-			} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
-				result = (Float.parseFloat(sArg0) == Float.parseFloat(sArg1));
-			} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
-				result = (Long.parseLong(sArg0) == Long.parseLong(sArg1));
-			} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
-				result = (Integer.parseInt(sArg0) == Integer.parseInt(sArg1));
-			} else if (arg0.getType().equals(typeString) || arg1.getType().equals(typeString)) {
-				result = sArg0.toString().equals(sArg1.toString());
-			}
-			if (result) {
-				return new Constant(true_);
-			} else {
-				return new Constant(false_);
-			}
-		}
-	});
-	public static final Symbol neq = new Symbol(Parser.NEQ, 2, Symbol.Type.INFIX, new Symbol.IImplGenerator() {
-		@Override
-		public String generate(Type type, Type[] childrenTypes, String[] children, String[] childrenSideEffects, String[] sideEffect) {
-			for (String s: childrenSideEffects) {
-				sideEffect[0] += s;
-			}
-			if (childrenTypes[0].equals(typeString) && childrenTypes[1].equals(typeString)) {
-				return "!" + children[0] + ".equals(" + children[1] + ")";
-			}
-			return "(" + children[0] + "!=" + children[1] + ")";
-		}
-	}, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (!(args.get(0).getClass() == Constant.class)) {
-				return null;
-			}
-			if (!(args.get(1).getClass() == Constant.class)) {
-				return null;
-			}
-			Constant arg0 = (Constant) args.get(0);
-			Constant arg1 = (Constant) args.get(1);
-			String sArg0 = arg0.getSymbol().toString();
-			String sArg1 = arg1.getSymbol().toString();
-			boolean result = false;
-			if (arg0.getType() == null || arg1.getType() == null) {
-				if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
-					result = Double.parseDouble(sArg0) != Double.parseDouble(sArg1);
-				} else {
-					result = Integer.parseInt(sArg0) != Integer.parseInt(sArg1);
-				}
-			}
-			if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
-				result = (Double.parseDouble(sArg0) != Double.parseDouble(sArg1));
-			} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
-				result = (Float.parseFloat(sArg0) != Float.parseFloat(sArg1));
-			} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
-				result = (Long.parseLong(sArg0) != Long.parseLong(sArg1));
-			} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
-				result = (Integer.parseInt(sArg0) != Integer.parseInt(sArg1));
-			} else if (arg0.getType().equals(typeString) || arg1.getType().equals(typeString)) {
-				result = !(sArg0.toString().equals(sArg1.toString()));
-			}
-			if (result) {
-				return new Constant(true_);
-			} else {
-				return new Constant(false_);
-			}
-		}
-	});
-	public static final Symbol gt = new Symbol(Parser.GT, 2, Symbol.Type.INFIX, ">", Symbol.Type.INFIX, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (!(args.get(0).getClass() == Constant.class)) {
-				return null;
-			}
-			if (!(args.get(1).getClass() == Constant.class)) {
-				return null;
-			}
-			Constant arg0 = (Constant) args.get(0);
-			Constant arg1 = (Constant) args.get(1);
-			String sArg0 = arg0.getSymbol().toString();
-			String sArg1 = arg1.getSymbol().toString();
-			boolean result = false;
-			if (arg0.getType() == null || arg1.getType() == null) {
-				if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
-					result = Double.parseDouble(sArg0) > Double.parseDouble(sArg1);
-				} else {
-					result = Integer.parseInt(sArg0) > Integer.parseInt(sArg1);
-				}
-			}
-			if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
-				result = (Double.parseDouble(sArg0) > Double.parseDouble(sArg1));
-			} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
-				result = (Float.parseFloat(sArg0) > Float.parseFloat(sArg1));
-			} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
-				result = (Long.parseLong(sArg0) > Long.parseLong(sArg1));
-			} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
-				result = (Integer.parseInt(sArg0) > Integer.parseInt(sArg1));
-			}
-			if (result) {
-				return new Constant(true_);
-			} else {
-				return new Constant(false_);
-			}
-		}
-	});
-	public static final Symbol lt = new Symbol(Parser.LT, 2, Symbol.Type.INFIX, "<", Symbol.Type.INFIX, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (!(args.get(0).getClass() == Constant.class)) {
-				return null;
-			}
-			if (!(args.get(1).getClass() == Constant.class)) {
-				return null;
-			}
-			Constant arg0 = (Constant) args.get(0);
-			Constant arg1 = (Constant) args.get(1);
-			String sArg0 = arg0.getSymbol().toString();
-			String sArg1 = arg1.getSymbol().toString();
-			boolean result = false;
-			if (arg0.getType() == null || arg1.getType() == null) {
-				if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
-					result = Double.parseDouble(sArg0) < Double.parseDouble(sArg1);
-				} else {
-					result = Integer.parseInt(sArg0) < Integer.parseInt(sArg1);
-				}
-			}
-			if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
-				result = (Double.parseDouble(sArg0) < Double.parseDouble(sArg1));
-			} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
-				result = (Float.parseFloat(sArg0) < Float.parseFloat(sArg1));
-			} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
-				result = (Long.parseLong(sArg0) < Long.parseLong(sArg1));
-			} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
-				result = (Integer.parseInt(sArg0) < Integer.parseInt(sArg1));
-			}
-			if (result) {
-				return new Constant(true_);
-			} else {
-				return new Constant(false_);
-			}
-		}
-	});
-	public static final Symbol ge = new Symbol(Parser.GE, 2, Symbol.Type.INFIX, ">=", Symbol.Type.INFIX, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (!(args.get(0).getClass() == Constant.class)) {
-				return null;
-			}
-			if (!(args.get(1).getClass() == Constant.class)) {
-				return null;
-			}
-			Constant arg0 = (Constant) args.get(0);
-			Constant arg1 = (Constant) args.get(1);
-			String sArg0 = arg0.getSymbol().toString();
-			String sArg1 = arg1.getSymbol().toString();
-			boolean result = false;
-			if (arg0.getType() == null || arg1.getType() == null) {
-				if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
-					result = Double.parseDouble(sArg0) >= Double.parseDouble(sArg1);
-				} else {
-					result = Integer.parseInt(sArg0) >= Integer.parseInt(sArg1);
-				}
-			}
-			if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
-				result = (Double.parseDouble(sArg0) >= Double.parseDouble(sArg1));
-			} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
-				result = (Float.parseFloat(sArg0) >= Float.parseFloat(sArg1));
-			} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
-				result = (Long.parseLong(sArg0) >= Long.parseLong(sArg1));
-			} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
-				result = (Integer.parseInt(sArg0) >= Integer.parseInt(sArg1));
-			}
-			if (result) {
-				return new Constant(true_);
-			} else {
-				return new Constant(false_);
-			}
-		}
-	});
-	public static final Symbol le = new Symbol(Parser.LE, 2, Symbol.Type.INFIX, "<=", Symbol.Type.INFIX, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (!(args.get(0).getClass() == Constant.class)) {
-				return null;
-			}
-			if (!(args.get(1).getClass() == Constant.class)) {
-				return null;
-			}
-			Constant arg0 = (Constant) args.get(0);
-			Constant arg1 = (Constant) args.get(1);
-			String sArg0 = arg0.getSymbol().toString();
-			String sArg1 = arg1.getSymbol().toString();
-			boolean result = false;
-			if (arg0.getType() == null || arg1.getType() == null) {
-				if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
-					result = Double.parseDouble(sArg0) <= Double.parseDouble(sArg1);
-				} else {
-					result = Integer.parseInt(sArg0) <= Integer.parseInt(sArg1);
-				}
-			}
-			if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
-				result = (Double.parseDouble(sArg0) <= Double.parseDouble(sArg1));
-			} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
-				result = (Float.parseFloat(sArg0) <= Float.parseFloat(sArg1));
-			} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
-				result = (Long.parseLong(sArg0) <= Long.parseLong(sArg1));
-			} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
-				result = (Integer.parseInt(sArg0) <= Integer.parseInt(sArg1));
-			}
-			if (result) {
-				return new Constant(true_);
-			} else {
-				return new Constant(false_);
-			}
-		}
-	});
-	public static final Symbol and = new Symbol(Parser.AND, 2, Symbol.Type.INFIX, "&&", Symbol.Type.INFIX, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (!(args.get(0).getClass() == Constant.class)) {
-				return null;
-			}
-			if (!(args.get(1).getClass() == Constant.class)) {
-				return null;
-			}
-			Constant arg0 = (Constant) args.get(0);
-			Constant arg1 = (Constant) args.get(1);
-			String sArg0 = arg0.getSymbol().toString();
-			String sArg1 = arg1.getSymbol().toString();
-			boolean result = false;
-			if (arg0.getType() == null || arg1.getType() == null) return null;
-			if (arg0.getType().equals(typeBoolean) || arg1.getType().equals(typeBoolean)) {
-				result = (Boolean.parseBoolean(sArg0) && Boolean.parseBoolean(sArg1));
-			}
-			if (result) {
-				return new Constant(true_);
-			} else {
-				return new Constant(false_);
-			}
-		}
-	});
-	public static final Symbol or = new Symbol(Parser.OR, 2, Symbol.Type.INFIX, "||", Symbol.Type.INFIX, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (!(args.get(0).getClass() == Constant.class)) {
-				return null;
-			}
-			if (!(args.get(1).getClass() == Constant.class)) {
-				return null;
-			}
-			Constant arg0 = (Constant) args.get(0);
-			Constant arg1 = (Constant) args.get(1);
-			String sArg0 = arg0.getSymbol().toString();
-			String sArg1 = arg1.getSymbol().toString();
-			boolean result = false;
-			if (arg0.getType() == null || arg1.getType() == null) return null;
-			if (arg0.getType().equals(typeBoolean) || arg1.getType().equals(typeBoolean)) {
-				result = (Boolean.parseBoolean(sArg0) || Boolean.parseBoolean(sArg1));
-			}
-			if (result) {
-				return new Constant(true_);
-			} else {
-				return new Constant(false_);
-			}
-		}
-	});
-	public static final Symbol neg = new Symbol(Parser.NEG, 1, Symbol.Type.PREFIX, "!", Symbol.Type.PREFIX, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (!(args.get(0).getClass() == Constant.class)) {
-				return null;
-			}
-			Constant arg0 = (Constant) args.get(0);
-			String sArg0 = arg0.getSymbol().toString();
-			boolean result = false;
-			if (arg0.getType() == null) return null;
-			if (arg0.getType().equals(typeBoolean)) {
-				result = !Boolean.parseBoolean(sArg0);
-			}
-			if (result) {
-				return new Constant(true_);
-			} else {
-				return new Constant(false_);
-			}
-		}
-	});
-	public static final Symbol cons = new Symbol("cons", 2, Symbol.Type.PREFIX, "($x,$y)->$x.add(0, $y)", Symbol.Type.LAMBDA_WITH_SIDE_EFFECT, new int[] {1, 0});
-	public static final Symbol append = new Symbol("append", 2, Symbol.Type.PREFIX, "add", Symbol.Type.METHOD_WITH_SIDE_EFFECT);		// Don't calculate here (Calculated in simulator).
-	public static final Symbol remove = new Symbol("remove", 2, Symbol.Type.PREFIX, "remove", Symbol.Type.METHOD_WITH_SIDE_EFFECT);		// Don't calculate here (Calculated in simulator).
-	public static final Symbol head = new Symbol("head", 1, Symbol.Type.PREFIX, "($x)->$x.get(0)", Symbol.Type.LAMBDA);
-	public static final Symbol tail = new Symbol("tail", 1, Symbol.Type.PREFIX, "($x)->$x.subList(1, $x.size())", Symbol.Type.LAMBDA);
-	public static final Symbol length = new Symbol("length", 1, Symbol.Type.PREFIX, "($x)->$x.size()", Symbol.Type.LAMBDA, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (args.get(0).getClass() == Constant.class && ((Constant) args.get(0)).getSymbol().equals(nil)) {
-				return new Constant("0", typeInt);
-			}
-			if (args.get(0) instanceof Term) {
-				Term term = (Term) args.get(0);
-				Type type = term.getType();
-				if (typeList.isAncestorOf(type)) {
-					int len = 0;
-					while (term.getSymbol().equals(DataConstraintModel.append)) {
-						len++;
-						term = (Term) term.getChild(0);
-					}
-					if (term instanceof ListTerm) {
-						len += ((ListTerm) term).getChildren().size();
-						return new Constant(Integer.toString(len), typeInt);
-					}
-				} else if (typeMap.isAncestorOf(type)) {
-					HashSet<String> keySet = new HashSet<>();
-					while (term.getSymbol().equals(DataConstraintModel.insert)) {
-						if (term.getChild(1).getClass() == Constant.class) {
-							keySet.add((String) ((Constant) term.getChild(1)).getValue());
-						}
-						term = (Term) term.getChild(0);
-					}
-					if (term instanceof MapTerm) {
-						keySet.addAll(((MapTerm) term).keySet());
-						return new Constant(Integer.toString(keySet.size()), typeInt);
-					}
-				} else if (typeJson.isAncestorOf(type)) {
-					HashSet<String> keySet = new HashSet<>();
-					while (term.getSymbol().equals(DataConstraintModel.addMember)) {
-						if (term.getChild(1).getClass() == Constant.class) {
-							keySet.add((String) ((Constant) term.getChild(1)).getValue());
-						}
-						term = (Term) term.getChild(0);
-					}
-					if (term instanceof JsonTerm) {
-						keySet.addAll(((JsonTerm) term).keySet());
-						return new Constant(Integer.toString(keySet.size()), typeInt);
-					}
-				}
-			}
-			return null;
-		}
-	});
-	public static final Symbol get = new Symbol("get", 2, Symbol.Type.PREFIX, "get", Symbol.Type.METHOD, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (args.get(1).getClass() == Constant.class && ((Constant) args.get(1)).getType().equals(typeInt)) {
-				int idx = Integer.parseInt(((Constant) args.get(1)).toString());
-				if (args.get(0) instanceof Term) {
-					Term term = (Term) args.get(0);
-					Type type = term.getType();
-					if (typeList.isAncestorOf(type)) {
-						Stack<Expression> appendedChldren = new Stack<>();
-						while (term.getSymbol().equals(DataConstraintModel.append)) {
-							if (!(term.getChild(0) instanceof Term)) {
-								return null;
-							}
-							appendedChldren.push(term.getChild(1));
-							term = (Term) term.getChild(0);
-						}
-						if (term instanceof ListTerm) {
-							ListTerm listTerm = (ListTerm) term.clone();
-							for (Expression child: appendedChldren) {
-								listTerm.append(child);
-							}
-							return listTerm.get(idx);
-						}
-					}
-				}
-			}
-			return null;
-		}
-	});
-	public static final Symbol set = new Symbol("set", 3, Symbol.Type.PREFIX, "set", Symbol.Type.METHOD_WITH_SIDE_EFFECT);				// Don't calculate here (Calculated in simulator).
-	public static final Symbol contains = new Symbol("contains", 2, Symbol.Type.PREFIX, new Symbol.IImplGenerator() {
-		@Override
-		public String generate(Type type, Type[] childrenTypes, String[] childrenImpl, String[] childrenSideEffects, String[] sideEffect) {
-			for (String s: childrenSideEffects) {
-				sideEffect[0] += s;
-			}
-			if (childrenTypes[0] != null && (typeMap.isAncestorOf(childrenTypes[0]) || typeJson.isAncestorOf(childrenTypes[0]))) {
-				return childrenImpl[0] + "." + "containsKey(" + childrenImpl[1] + ")";
-			}
-			return childrenImpl[0] + "." + "contains(" + childrenImpl[1] + ")";
-		}
-	}, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (args.get(0).getClass() == Constant.class && ((Constant) args.get(0)).getSymbol().equals(nil)) {
-				return new Constant(false_);
-			}
-			if (args.get(0) instanceof Term) {
-				Term term = (Term) args.get(0);
-				Type type = term.getType();
-				if (typeList.isAncestorOf(type)) {
-					while (term.getSymbol().equals(DataConstraintModel.append)) {
-						if (term.getChild(1).equals(args.get(1))) {
-							return new Constant(true_);
-						}
-						if (!(term.getChild(0) instanceof Term)) {
-							return new Constant(false_);
-						}
-						term = (Term) term.getChild(0);
-					}
-					if (term instanceof ListTerm) {
-						for (Expression element: term.getChildren()) {
-							if (element.equals(args.get(1))) {
-								return new Constant(true_);
-							}
-						}
-						return new Constant(false_);
-					}
-				} else if (typeMap.isAncestorOf(type)) {
-					while (term.getSymbol().equals(DataConstraintModel.insert)) {
-						if (term.getChild(1).equals(args.get(1))) {
-							return new Constant(true_);
-						}
-						if (!(term.getChild(0) instanceof Term)) {
-							return new Constant(false_);
-						}
-						term = (Term) term.getChild(0);
-					}
-					if (term instanceof MapTerm) {
-						String key;
-						if (args.get(1) instanceof Constant) {
-							key = (String) ((Constant) args.get(1)).getValue();
-						} else {
-							key = args.get(1).toString();
-						}
-						if (((MapTerm) term).keySet().contains(key)) {
-							return new Constant(true_);
-						}
-						return new Constant(false_);
-					}
-				} else if (typeJson.isAncestorOf(type)) {
-					while (term.getSymbol().equals(DataConstraintModel.addMember)) {
-						if (term.getChild(1).equals(args.get(1))) {
-							return new Constant(true_);
-						}
-						if (!(term.getChild(0) instanceof Term)) {
-							return new Constant(false_);
-						}
-						term = (Term) term.getChild(0);
-					}
-					if (term instanceof JsonTerm) {
-						String key;
-						if (args.get(1) instanceof Constant) {
-							key = (String) ((Constant) args.get(1)).getValue();
-						} else {
-							key = args.get(1).toString();
-						}
-						if (((JsonTerm) term).keySet().contains(key)) {
-							return new Constant(true_);
-						}
-						return new Constant(false_);
-					}
-				}
-			}
-			return null;
-		}
-	});
-	public static final Symbol indexOf = new Symbol("indexOf", 2, Symbol.Type.PREFIX, "indexOf", Symbol.Type.METHOD, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (args.get(0) instanceof Term) {
-				Term term = (Term) args.get(0);
-				Type type = term.getType();
-				if (typeList.isAncestorOf(type)) {
-					Stack<Expression> appendedChldren = new Stack<>();
-					while (term.getSymbol().equals(DataConstraintModel.append)) {
-						if (!(term.getChild(0) instanceof Term)) {
-							return null;
-						}
-						appendedChldren.push(term.getChild(1));
-						term = (Term) term.getChild(0);
-					}
-					if (term instanceof ListTerm) {
-						int idx = 0;
-						ListTerm listTerm = (ListTerm) term;
-						for (Expression child: listTerm.getChildren()) {
-							if (child.equals(args.get(1))) {
-								return new Constant(Integer.toString(idx), typeInt);
-							}
-							idx++;
-						}
-						for (Expression child: appendedChldren) {
-							if (child.equals(args.get(1))) {
-								return new Constant(Integer.toString(idx), typeInt);
-							}
-							idx++;
-						}
-					}
-				}
-			}
-			return null;
-		}
-	});
-	public static final Symbol nil = new Symbol("nil", 0, Symbol.Type.PREFIX, new Symbol.IImplGenerator() {
-		final int count[] = {0};
-		@Override
-		public String generate(Type type, Type[] childrenTypes, String[] children, String[] childrenSideEffects, String[] sideEffect) {
-			String compType = "";
-			if (type != null) {
-				String interfaceType = type.getInterfaceTypeName();
-				if (interfaceType.contains("<")) {
-					compType = interfaceType.substring(interfaceType.indexOf("<") + 1, interfaceType.lastIndexOf(">"));
-				}
-				String implType = type.getImplementationTypeName();
-				if (implType.indexOf('<') >= 0) {
-					implType = implType.substring(0, implType.indexOf('<'));
-				}
-				if (sideEffect == null) {
-					return "new " + implType + "<>()";
-				} else {
-					String temp = "temp_nil" + count[0];
-					if (sideEffect[0] == null) {
-						sideEffect[0] = "";
-					}
-					sideEffect[0] += interfaceType + " " + temp + " = " + "new " + implType + "<" + compType + ">();\n";
-					count[0]++;
-					return temp;
-				}
-			}			
-			return "new ArrayList<" + compType + ">()";
-		}
-	}, true);
-	public static final Symbol null_ = new Symbol("null", 0, Symbol.Type.PREFIX, "null", Symbol.Type.PREFIX);
-	public static final Symbol true_ = new Symbol("true", 0, Symbol.Type.PREFIX, "true", Symbol.Type.PREFIX);
-	public static final Symbol false_ = new Symbol("false", 0, Symbol.Type.PREFIX, "false", Symbol.Type.PREFIX);
-	public static final Symbol cond = new Symbol("if", 3, Symbol.Type.PREFIX, new Symbol.IImplGenerator() {
-		final int count[] = {0};
-		@Override
-		public String generate(Type type, Type[] childrenTypes, String[] childrenImpl, String[] childrenSideEffects, String[] sideEffect) {
-			String temp = "temp_if" + count[0];
-			String impl = ""; 
-			
-			impl += type.getInterfaceTypeName() + " " + temp + ";\n";
-			if (childrenSideEffects[0] != null && childrenSideEffects[0].length() > 0) impl += childrenSideEffects[0];
-			impl += "if (" + childrenImpl[0] + ") {\n";
-			if (childrenSideEffects[1] != null && childrenSideEffects[1].length() > 0) impl += "\t" + childrenSideEffects[1];
-			impl += "\t" + temp + " = " + childrenImpl[1] + ";\n";
-			impl += "} else {\n";
-			if (childrenSideEffects[2] != null && childrenSideEffects[2].length() > 0) impl += "\t" + childrenSideEffects[2];
-			impl += "\t" + temp + " = " + childrenImpl[2] + ";\n";
-			impl += "}\n";
-			
-			sideEffect[0] += impl;
-			
-			count[0]++;
-			return temp;
-		}
-	}, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (!(args.get(0).getClass() == Constant.class)) return null;
-			if (((Constant) args.get(0)).getSymbol().equals(true_)) {
-				return args.get(1);
-			} else if (((Constant) args.get(0)).getSymbol().equals(false_)) {
-				return args.get(2);
-			}
-			return null;
-		}
-	});
-	public static final Symbol pair = new Symbol("pair", -1, Symbol.Type.PREFIX, new Symbol.IImplGenerator() {
-		@Override
-		public String generate(Type type, Type[] childrenTypes, String[] childrenImpl, String[] childrenSideEffects, String[] sideEffect) {
-			for (String s: childrenSideEffects) {
-				sideEffect[0] += s;
-			}
-			String impl = "new Pair<>(" + childrenImpl[0] + "," + childrenImpl[1] + ")";
-			return impl;
-		}
-	});
-	public static final Symbol tuple = new Symbol("tuple", -1, Symbol.Type.PREFIX, new Symbol.IImplGenerator() {
-		@Override
-		public String generate(Type type, Type[] childrenTypes, String[] childrenImpl, String[] childrenSideEffects, String[] sideEffect) {
-			for (String s: childrenSideEffects) {
-				sideEffect[0] += s;
-			}
-			String impl = "new AbstractMap.SimpleEntry<>(" + childrenImpl[0] + "$x)";
-			for (int i = 1; i < childrenImpl.length - 1; i++) {
-				impl = impl.replace("$x", ", new AbstractMap.SimpleEntry<>(" + childrenImpl[i] + "$x)");
-			}
-			impl = impl.replace("$x", ", " + childrenImpl[childrenImpl.length - 1]);
-			return impl;
-		}
-	});
-	public static final Symbol fst = new Symbol("fst", 1, Symbol.Type.PREFIX, "getKey", Symbol.Type.METHOD);
-	public static final Symbol snd = new Symbol("snd", 1, Symbol.Type.PREFIX, "getValue", Symbol.Type.METHOD);
-	public static final Symbol left = new Symbol("left", 1, Symbol.Type.PREFIX, "getLeft", Symbol.Type.METHOD);
-	public static final Symbol right = new Symbol("right", 1, Symbol.Type.PREFIX, "getRight", Symbol.Type.METHOD);
-	public static final Symbol insert = new Symbol("insert", 3, Symbol.Type.PREFIX, "put", Symbol.Type.METHOD_WITH_SIDE_EFFECT);		// Don't calculate here (Calculated in simulator).
-	public static final Symbol delete = new Symbol("delete", 2, Symbol.Type.PREFIX, "remove", Symbol.Type.METHOD_WITH_SIDE_EFFECT);		// Don't calculate here (Calculated in simulator).
-	public static final Symbol lookup = new Symbol("lookup", 2, Symbol.Type.PREFIX, "get", Symbol.Type.METHOD, new Symbol.ICalculator() {
-		@Override
-		public Expression calculate(List<Expression> args) {
-			if (args.get(1).getClass() == Constant.class && ((Constant) args.get(1)).getType().equals(typeString)) {
-				String key = (String) ((Constant) args.get(1)).getValue();
-				if (args.get(0) instanceof Term) {
-					Term term = (Term) args.get(0);
-					Type type = term.getType();
-					if (typeMap.isAncestorOf(type)) {
-						Stack<Map.Entry<Expression, Expression>> appendedChldren = new Stack<>();
-						while (term.getSymbol().equals(DataConstraintModel.insert)) {
-							if (!(term.getChild(0) instanceof Term)) {
-								return null;
-							}
-							appendedChldren.push(new AbstractMap.SimpleEntry<>(term.getChild(0), term.getChild(1)));
-							term = (Term) term.getChild(0);
-						}
-						if (term instanceof MapTerm) {
-							MapTerm mapTerm = (MapTerm) term.clone();
-							for (Map.Entry<Expression, Expression> childEnt: appendedChldren) {
-								if (childEnt.getKey().getClass() == Constant.class)
-								mapTerm.insert((String) ((Constant) childEnt.getKey()).getValue(), childEnt.getValue());
-							}
-							return mapTerm.get(key);
-						}
-					}
-				}
-			}
-			return null;
-		}
-	});
-	public static final Symbol addMember = new Symbol("addMember", 3, Symbol.Type.PREFIX, "put", Symbol.Type.METHOD_WITH_SIDE_EFFECT);
-	public static final Symbol dot = new Symbol(Parser.DOT, 2, Symbol.Type.INFIX, "get", Symbol.Type.METHOD);
-	public static final Symbol dotParam = new Symbol(Parser.DOT, 2, Symbol.Type.INFIX, "get", Symbol.Type.METHOD);
-	public static final Symbol pi = new Symbol("PI", 0, Symbol.Type.PREFIX, "Math.PI", Symbol.Type.PREFIX);
-	public static final Symbol E = new Symbol("E", 0, Symbol.Type.PREFIX, "Math.E", Symbol.Type.PREFIX);
-	public static final Symbol sqrt = new Symbol("sqrt", 1, Symbol.Type.PREFIX, "Math.sqrt", Symbol.Type.PREFIX);
-	public static final Symbol sin = new Symbol("sin", 1, Symbol.Type.PREFIX, "Math.sin", Symbol.Type.PREFIX);
-	public static final Symbol cos = new Symbol("cos", 1, Symbol.Type.PREFIX, "Math.cos", Symbol.Type.PREFIX);
-	public static final Symbol tan = new Symbol("tan", 1, Symbol.Type.PREFIX, "Math.tan", Symbol.Type.PREFIX);
-	public static final Symbol asin = new Symbol("asin", 1, Symbol.Type.PREFIX, "Math.asin", Symbol.Type.PREFIX);
-	public static final Symbol acos = new Symbol("acos", 1, Symbol.Type.PREFIX, "Math.acos", Symbol.Type.PREFIX);
-	public static final Symbol atan = new Symbol("atan", 1, Symbol.Type.PREFIX, "Math.atan", Symbol.Type.PREFIX);
-	public static final Symbol pow = new Symbol("pow", 2, Symbol.Type.PREFIX, "Math.pow", Symbol.Type.PREFIX);
-	public static final Symbol exp = new Symbol("exp", 1, Symbol.Type.PREFIX, "Math.exp", Symbol.Type.PREFIX);
-	public static final Symbol log = new Symbol("log", 1, Symbol.Type.PREFIX, "Math.log", Symbol.Type.PREFIX);
-	public static final Symbol abs = new Symbol("abs", 1, Symbol.Type.PREFIX, "Math.abs", Symbol.Type.PREFIX);
-		
-	static {
-		add.setInverses(new Symbol[] {sub, sub});
-		mul.setInverses(new Symbol[] {div, div});
-		sub.setInverses(new Symbol[] {add});
-		div.setInverses(new Symbol[] {mul});
-		minus.setInverses(new Symbol[] {minus});
-		mod.setSignature(new Type[] {typeInt, null, null});
-		eq.setSignature(new Type[] {typeBoolean, null, null});
-		neq.setSignature(new Type[] {typeBoolean, null, null});
-		gt.setSignature(new Type[] {typeBoolean, null, null});
-		lt.setSignature(new Type[] {typeBoolean, null, null});
-		ge.setSignature(new Type[] {typeBoolean, null, null});
-		le.setSignature(new Type[] {typeBoolean, null, null});
-		and.setSignature(new Type[] {typeBoolean, typeBoolean, typeBoolean});
-		or.setSignature(new Type[] {typeBoolean, typeBoolean, typeBoolean});
-		neg.setSignature(new Type[] {typeBoolean, typeBoolean});
-		cons.setInverses(new Symbol[] {head, tail});
-		cons.setSignature(new Type[] {typeList, null, typeList});
-		append.setSignature(new Type[] {typeList, typeList, null});
-		remove.setSignature(new Type[] {typeList, typeList, typeInt});
-		head.setSignature(new Type[] {null, typeList});
-		tail.setSignature(new Type[] {typeList, typeList});
-		contains.setSignature(new Type[] {typeBoolean, null, null});
-		indexOf.setSignature(new Type[] {typeInt, typeList, null});
-		length.setSignature(new Type[] {typeInt, null});
-		get.setSignature(new Type[] {null, typeList, typeInt});
-		set.setSignature(new Type[] {typeList, typeList, typeInt, null});
-		null_.setSignature(new Type[] {null});
-		true_.setSignature(new Type[] {typeBoolean});
-		false_.setSignature(new Type[] {typeBoolean});
-		pair.setSignature(new Type[] {typePair,null,null});
-		pair.setInverses(new Symbol[] {left, right});
-		left.setSignature(new Type[] {null, typePair});
-		right.setSignature(new Type[] {null, typePair});
-		tuple.setSignature(new Type[] {typeTuple, null, null});
-		tuple.setInverses(new Symbol[] {fst, snd});
-		fst.setSignature(new Type[] {null, typeTuple});
-		fst.setInverses(new Symbol[] {new LambdaAbstraction(new Variable("x"), new Term(tuple, new Expression[] {new Variable("x"), new Variable("y")}))});
-		snd.setSignature(new Type[] {null, typeTuple});
-		snd.setInverses(new Symbol[] {new LambdaAbstraction(new Variable("y"), new Term(tuple, new Expression[] {new Variable("x"), new Variable("y")}))});
-		insert.setSignature(new Type[] {typeMap, typeMap, null, null});
-		delete.setSignature(new Type[] {typeMap, typeMap, null});
-		lookup.setSignature(new Type[] {null, typeMap, null});
-		addMember.setSignature(new Type[] {typeJson, typeJson, typeString, null});
-		dot.setSignature(new Type[] {null, typeJson, typeString});
-		dotParam.setSignature(new Type[] {null, null, null});
-		pi.setSignature(new Type[] {typeDouble});
-		E.setSignature(new Type[] {typeDouble});
-		sqrt.setSignature(new Type[] {typeDouble, typeDouble});
-		sin.setSignature(new Type[] {typeDouble, typeDouble});
-		cos.setSignature(new Type[] {typeDouble, typeDouble});
-		tan.setSignature(new Type[] {typeDouble, typeDouble});
-		asin.setSignature(new Type[] {typeDouble, typeDouble});
-		asin.setInverses(new Symbol[] {sin});
-		acos.setSignature(new Type[] {typeDouble, typeDouble});
-		acos.setInverses(new Symbol[] {cos});
-		atan.setSignature(new Type[] {typeDouble, typeDouble});
-		atan.setInverses(new Symbol[] {tan});
-		pow.setSignature(new Type[] {typeDouble, typeDouble, typeDouble});
-		exp.setSignature(new Type[] {typeDouble, typeDouble});
-		exp.setInverses(new Symbol[] {log});
-		log.setSignature(new Type[] {typeDouble, typeDouble});
-		log.setInverses(new Symbol[] {exp});
-		abs.setSignature(new Type[] {typeDouble, typeDouble});
-	}
-	
-	public DataConstraintModel() {
-		resourcePaths = new ArrayList<>();
-		resourceHierarchies = new HashMap<>();
-		channels = new HashMap<>();
-		inputChannels = new HashMap<>();
-		types = new HashMap<>();
-		addType(typeInt);
-		addType(typeLong);
-		addType(typeFloat);
-		addType(typeDouble);
-		addType(typeBoolean);
-		addType(typeString);
-		addType(typeList);
-		addType(typePair);
-		addType(typeTuple);
-		addType(typeMap);
-		addType(typeJson);
-		symbols = new HashMap<>();
-		addSymbol(add);
-		addSymbol(mul);
-		addSymbol(sub);
-		addSymbol(div);
-		addSymbol(minus);
-		addSymbol(mod);
-		addSymbol(eq);
-		addSymbol(neq);
-		addSymbol(gt);
-		addSymbol(lt);
-		addSymbol(ge);
-		addSymbol(le);
-		addSymbol(and);
-		addSymbol(or);
-		addSymbol(neg);
-		addSymbol(cons);
-		addSymbol(append);
-		addSymbol(remove);
-		addSymbol(head);
-		addSymbol(tail);
-		addSymbol(length);
-		addSymbol(contains);
-		addSymbol(indexOf);
-		addSymbol(get);
-		addSymbol(set);
-		addSymbol(cond);
-		addSymbol(nil);
-		addSymbol(null_);
-		addSymbol(true_);
-		addSymbol(false_);
-		addSymbol(pair);
-		addSymbol(left);
-		addSymbol(right);
-		addSymbol(tuple);
-		addSymbol(fst);
-		addSymbol(snd);
-		addSymbol(insert);
-		addSymbol(delete);
-		addSymbol(lookup);
-		addSymbol(addMember);
-		addSymbol(dot);
-		addSymbol(dotParam);
-		addSymbol(pi);
-		addSymbol(E);
-		addSymbol(sqrt);
-		addSymbol(sin);
-		addSymbol(cos);
-		addSymbol(tan);
-		addSymbol(asin);
-		addSymbol(acos);
-		addSymbol(atan);
-		addSymbol(pow);
-		addSymbol(exp);
-		addSymbol(log);
-		addSymbol(abs);
-	}
-	
-	public Collection<ResourceHierarchy> getResourceHierarchies() {
-		return resourceHierarchies.values();
-	}
-	
-	public ResourceHierarchy getResourceHierarchy(String hierarchy) {
-		return resourceHierarchies.get(hierarchy);
-	}
-	
-	public ResourceHierarchy getOrPutResourceHierarchy(ResourceHierarchy resourceHierarchy) {
-		String hierarchy = resourceHierarchy.toString();
-		if (resourceHierarchies.get(hierarchy) != null) {
-			return resourceHierarchies.get(hierarchy);
-		}
-		resourceHierarchies.put(hierarchy, resourceHierarchy);
-		return resourceHierarchy;
-	}
-	
-	public List<ResourcePath> getResourcePaths() {
-		return resourcePaths;
-	}
-	
-	public void addResourcePath(ResourcePath resourcePath) {
-		resourcePaths.add(resourcePath);
-		ResourceHierarchy childHierarchy = null;
-		ResourceHierarchy hierarchy = null;
-		do {
-			hierarchy = resourcePath.getResourceHierarchy();
-			if (hierarchy != null && resourceHierarchies.get(hierarchy.toString()) == null) {
-				resourceHierarchies.put(hierarchy.toString(), hierarchy);				
-			} else {
-				hierarchy = resourceHierarchies.get(hierarchy.toString());
-				resourcePath.setResourceHierarchy(hierarchy);
-				if (childHierarchy != null) {
-					childHierarchy.setParent(hierarchy);
-				}
-			}
-			resourcePath = resourcePath.getParent();
-			childHierarchy = hierarchy;
-		} while (resourcePath != null);
-	}
-	
-	public void setResourcePaths(List<ResourcePath> resourcePaths) {
-		this.resourcePaths = resourcePaths;
-	}
-	
-	public ResourcePath getResourcePath(String path) {
-		for (ResourcePath resourcePath: resourcePaths) {
-			if (resourcePath.toString().equals(path)) return resourcePath;
-		}
-		return null;
-	}
-	
-	public void removeResourcePath(String path) {
-		ResourcePath resourcePath = getResourcePath(path);
-		if (resourcePath == null) return;
-		resourcePaths.remove(resourcePath);
-		for (Channel ch: channels.values()) {
-			ch.removeChannelMember(resourcePath);
-		}
-		for (Channel ch: inputChannels.values()) {
-			ch.removeChannelMember(resourcePath);
-		}
-	}
-
-	public Collection<Channel> getChannels() {
-		return channels.values();
-	}
-		
-	public Channel getChannel(String channelName) {
-		return channels.get(channelName);
-	}
-	
-	public void setChannels(HashMap<String, Channel> channels) {
-		this.channels = channels;
-	}
-	
-	public void addChannel(Channel channel) {
-		channels.put(channel.getChannelName(), channel);
-	}
-	
-	public void removeChannel(String channelName) {
-		channels.remove(channelName);
-	}
-	
-	public Collection<Channel> getInputChannels() {
-		return inputChannels.values();
-	}
-	
-	public Channel getInputChannel(String channelName) {
-		return inputChannels.get(channelName);
-	}
-	
-	public void setInputChannels(HashMap<String, Channel> inputChannels) {
-		this.inputChannels = inputChannels;
-	}
-	
-	public void addInputChannel(Channel inputChannel) {
-		inputChannels.put(inputChannel.getChannelName(), inputChannel);
-	}
-	
-	public void removeInputChannel(String inputChannelName) {
-		inputChannels.remove(inputChannelName);
-	}
-	
-	public void addType(Type type) {
-		types.put(type.getTypeName(), type);
-	}
-	
-	public Type getType(String name) {
-		return types.get(name);
-	}
-	
-	public void addSymbol(Symbol symbol) {
-		symbols.put(symbol.getName(), symbol);
-	}
-	
-	public Symbol getSymbol(String name) {
-		return symbols.get(name);
-	}
-	
-	public static String getWrapperType(Type type) {
-		if (type == typeInt) {
-			return "Integer";
-		} else if (type == typeLong) {
-			return "Long";
-		} else if (type == typeFloat) {
-			return "Float";
-		} else if (type == typeDouble) {
-			return "Double";
-		} else if (type == typeBoolean) {
-			return "Boolean";
-		}
-		return null;
-	}
-	
-	public boolean isPrimitiveType(Type type) {
-		if (type == typeInt 
-			|| type == typeLong
-			|| type == typeFloat
-			|| type == typeDouble
-			|| type == typeBoolean) {
-			return true;
-		}
-		return false;
-	}
-
-	public static boolean isListType(Type type) {
-		return typeList.isAncestorOf(type);
-	}
-
-	public static String getDefaultValue(Type type) {
-		if (type == typeInt) {
-			return "0";
-		} else if (type == typeLong) {
-			return "0L";
-		} else if (type == typeFloat) {
-			return "0.0f";
-		} else if (type == typeDouble) {
-			return "0.0";
-		} else if (type == typeBoolean) {
-			return "false";
-		} else if (type == typeString) {
-			return "\"\"";
-		}
-		return "new " + type.getImplementationTypeName() + "()";
-	}
-	
-	@Override
-	public String toString() {
-		String out = "";
-		for (Channel channel: inputChannels.values()) {
-			out += channel.toString();
-		}
-		for (Channel channel: channels.values()) {
-			out += channel.toString();
-		}
-		return out;
-	}
-	
-	public String getSourceText() {
-		String out = "";
-		String init = "";
-		for (ResourceHierarchy resource: resourceHierarchies.values()) {
-			String initializer = resource.getInitText();
-			if (initializer != null) {
-				init += resource.toString() + " := " + initializer + "\n";
-			}
-		}
-		if (init.length() > 0) {
-			out += "init {\n" + init + "}\n";
-		}
-		for (Channel channel: inputChannels.values()) {
-			out += channel.getSourceText();
-		}
-		for (Channel channel: channels.values()) {
-			out += channel.getSourceText();
-		}
-		return out;
-	}
-}
+package models.dataConstraintModel;
+
+import java.util.AbstractMap;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Stack;
+
+import models.algebra.Constant;
+import models.algebra.Expression;
+import models.algebra.LambdaAbstraction;
+import models.algebra.Symbol;
+import models.algebra.Term;
+import models.algebra.Type;
+import models.algebra.Variable;
+import parser.Parser;
+
+public class DataConstraintModel {
+	protected List<ResourcePath> resourcePaths = null;
+	protected HashMap<String, ResourceHierarchy> resourceHierarchies = null;
+	protected HashMap<String, Channel> channels = null;
+	protected HashMap<String, Channel> inputChannels = null;
+	protected HashMap<String, Type> types = null;
+	protected HashMap<String, Symbol> symbols = null;
+	public static final Type typeInt = new Type("Int", "int");
+	public static final Type typeLong = new Type("Long", "long", typeInt);
+	public static final Type typeFloat = new Type("Float", "float", typeInt);
+	public static final Type typeDouble = new Type("Double", "double", typeFloat);
+	public static final Type typeBoolean = new Type("Bool", "boolean");
+	public static final Type typeString = new Type("Str", "String") {
+		public String valueToRepresentation(Object value) {
+			if (value instanceof String) {
+				return Parser.DOUBLE_QUOT + (String) value + Parser.DOUBLE_QUOT;
+			}
+			return value.toString();
+		}
+		public Object representationToValue(String representation) {
+			if (representation.startsWith(Parser.DOUBLE_QUOT) && representation.endsWith(Parser.DOUBLE_QUOT)) {
+				return representation.substring(1, representation.length() - 1);
+			}
+			return representation;
+		}
+	};
+	public static final Type typeList = new Type("List", "ArrayList", "List");
+	public static final Type typeListInt = new Type("List", "ArrayList<>", "List<Integer>", typeList);
+	public static final Type typeListStr = new Type("List", "ArrayList<>", "List<String>", typeList);
+	public static final Type typeTuple = new Type("Tuple", "AbstractMap.SimpleEntry", "Map.Entry");
+	public static final Type typePair = new Type("Pair", "Pair", "Pair");
+	public static final Type typePairInt = new Type("Pair", "Pair<Integer>", "Pair<Integer>", typePair);
+	public static final Type typePairStr = new Type("Pair", "Pair<String>", "Pair<String>", typePair);
+	public static final Type typePairDouble = new Type("Pair", "Pair<Double>", "Pair<Double>", typePair);
+	public static final Type typeMap = new Type("Map", "HashMap<>", "Map");
+	public static final JsonType typeJson = new JsonType("Json", "HashMap<>", "Map<String, Object>");
+	public static final Symbol add = new Symbol(Parser.ADD, 2, Symbol.Type.INFIX, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (!(args.get(0).getClass() == Constant.class)) {
+				return null;
+			}
+			if (!(args.get(1).getClass() == Constant.class)) {
+				return null;
+			}
+			Constant arg0 = (Constant) args.get(0);
+			Constant arg1 = (Constant) args.get(1);
+			String sArg0 = arg0.getSymbol().toString();
+			String sArg1 = arg1.getSymbol().toString();
+			if (arg0.getType() != null && arg1.getType() != null) {
+				if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
+					return new Constant(Double.toString(Double.parseDouble(sArg0) + Double.parseDouble(sArg1)), typeDouble);
+				} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
+					return new Constant(Float.toString(Float.parseFloat(sArg0) + Float.parseFloat(sArg1)), typeFloat);
+				} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
+					return new Constant(Long.toString(Long.parseLong(sArg0) + Long.parseLong(sArg1)), typeLong);
+				} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
+					return new Constant(Integer.toString(Integer.parseInt(sArg0) + Integer.parseInt(sArg1)), typeInt);
+				}
+			}
+			if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
+				return new Constant(Double.toString(Double.parseDouble(sArg0) + Double.parseDouble(sArg1)), typeDouble);
+			} else {
+				return new Constant(Integer.toString(Integer.parseInt(sArg0) + Integer.parseInt(sArg1)), typeInt);
+			}
+		}
+	});
+	public static final Symbol mul = new Symbol(Parser.MUL, 2, Symbol.Type.INFIX, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (!(args.get(0).getClass() == Constant.class)) {
+				return null;
+			}
+			if (!(args.get(1).getClass() == Constant.class)) {
+				return null;
+			}
+			Constant arg0 = (Constant) args.get(0);
+			Constant arg1 = (Constant) args.get(1);
+			String sArg0 = arg0.getSymbol().toString();
+			String sArg1 = arg1.getSymbol().toString();
+			if (arg0.getType() != null && arg1.getType() != null) {
+				if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
+					return new Constant(Double.toString(Double.parseDouble(sArg0) * Double.parseDouble(sArg1)), typeDouble);
+				} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
+					return new Constant(Float.toString(Float.parseFloat(sArg0) * Float.parseFloat(sArg1)), typeFloat);
+				} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
+					return new Constant(Long.toString(Long.parseLong(sArg0) * Long.parseLong(sArg1)), typeLong);
+				} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
+					return new Constant(Integer.toString(Integer.parseInt(sArg0) * Integer.parseInt(sArg1)), typeInt);
+				}
+			}
+			if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
+				return new Constant(Double.toString(Double.parseDouble(sArg0) * Double.parseDouble(sArg1)), typeDouble);
+			} else {
+				return new Constant(Integer.toString(Integer.parseInt(sArg0) * Integer.parseInt(sArg1)), typeInt);
+			}
+		}
+	});
+	public static final Symbol sub = new Symbol(Parser.SUB, 2, Symbol.Type.INFIX, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (!(args.get(0).getClass() == Constant.class)) {
+				return null;
+			}
+			if (!(args.get(1).getClass() == Constant.class)) {
+				return null;
+			}
+			Constant arg0 = (Constant) args.get(0);
+			Constant arg1 = (Constant) args.get(1);
+			String sArg0 = arg0.getSymbol().toString();
+			String sArg1 = arg1.getSymbol().toString();
+			if (arg0.getType() != null && arg1.getType() != null) {
+				if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
+					return new Constant(Double.toString(Double.parseDouble(sArg0) - Double.parseDouble(sArg1)), typeDouble);
+				} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
+					return new Constant(Float.toString(Float.parseFloat(sArg0) - Float.parseFloat(sArg1)), typeFloat);
+				} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
+					return new Constant(Long.toString(Long.parseLong(sArg0) - Long.parseLong(sArg1)), typeLong);
+				} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
+					return new Constant(Integer.toString(Integer.parseInt(sArg0) - Integer.parseInt(sArg1)), typeInt);
+				}
+			}
+			if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
+				return new Constant(Double.toString(Double.parseDouble(sArg0) - Double.parseDouble(sArg1)), typeDouble);
+			} else {
+				return new Constant(Integer.toString(Integer.parseInt(sArg0) - Integer.parseInt(sArg1)), typeInt);
+			}
+		}
+	});
+	public static final Symbol div = new Symbol(Parser.DIV, 2, Symbol.Type.INFIX, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (!(args.get(0).getClass() == Constant.class)) {
+				return null;
+			}
+			if (!(args.get(1).getClass() == Constant.class)) {
+				return null;
+			}
+			Constant arg0 = (Constant) args.get(0);
+			Constant arg1 = (Constant) args.get(1);
+			String sArg0 = arg0.getSymbol().toString();
+			String sArg1 = arg1.getSymbol().toString();
+			if (arg0.getType() != null && arg1.getType() != null) {
+				if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
+					return new Constant(Double.toString(Double.parseDouble(sArg0) / Double.parseDouble(sArg1)), typeDouble);
+				} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
+					return new Constant(Float.toString(Float.parseFloat(sArg0) / Float.parseFloat(sArg1)), typeFloat);
+				} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
+					return new Constant(Long.toString(Long.parseLong(sArg0) / Long.parseLong(sArg1)), typeLong);
+				} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
+					return new Constant(Integer.toString(Integer.parseInt(sArg0) / Integer.parseInt(sArg1)), typeInt);
+				}
+			}
+			if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
+				return new Constant(Double.toString(Double.parseDouble(sArg0) / Double.parseDouble(sArg1)), typeDouble);
+			} else {
+				return new Constant(Integer.toString(Integer.parseInt(sArg0) / Integer.parseInt(sArg1)), typeInt);
+			}
+		}
+	});
+	public static final Symbol mod = new Symbol(Parser.MOD, 2, Symbol.Type.INFIX, "%", Symbol.Type.INFIX, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (!(args.get(0).getClass() == Constant.class)) {
+				return null;
+			}
+			if (!(args.get(1).getClass() == Constant.class)) {
+				return null;
+			}
+			Constant arg0 = (Constant) args.get(0);
+			Constant arg1 = (Constant) args.get(1);
+			String sArg0 = arg0.getSymbol().toString();
+			String sArg1 = arg1.getSymbol().toString();
+			if (arg0.getType() != null && arg1.getType() != null) {
+				if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
+					return new Constant(Long.toString(Long.parseLong(sArg0) % Long.parseLong(sArg1)), typeLong);
+				} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
+					return new Constant(Integer.toString(Integer.parseInt(sArg0) % Integer.parseInt(sArg1)), typeInt);
+				}
+			}
+			return new Constant(Integer.toString(Integer.parseInt(sArg0) % Integer.parseInt(sArg1)));
+		}
+	});
+	public static final Symbol minus = new Symbol(Parser.MINUS, 1, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (!(args.get(0).getClass() == Constant.class)) {
+				return null;
+			}
+			Constant arg = (Constant) args.get(0);
+			String sArg = arg.getSymbol().toString();
+			if (arg.getType() != null) {
+				if (arg.getType().equals(typeDouble)) {
+					return new Constant(Double.toString(-Double.parseDouble(sArg)), typeDouble);
+				} else if (arg.getType().equals(typeFloat)) {
+					return new Constant(Float.toString(-Float.parseFloat(sArg)), typeFloat);
+				} else if (arg.getType().equals(typeLong)) {
+					return new Constant(Long.toString(-Long.parseLong(sArg)), typeLong);
+				} else if (arg.getType().equals(typeInt)) {
+					return new Constant(Integer.toString(-Integer.parseInt(sArg)), typeInt);
+				}
+			}
+			if (sArg.contains(Parser.DOT)) {
+				return new Constant(Double.toString(-Double.parseDouble(sArg)), typeDouble);
+			} else {
+				return new Constant(Integer.toString(-Integer.parseInt(sArg)), typeInt);
+			}
+		}
+	});
+	public static final Symbol eq = new Symbol(Parser.EQ, 2, Symbol.Type.INFIX, new Symbol.IImplGenerator() {
+		@Override
+		public String generate(Type type, Type[] childrenTypes, String[] children, String[] childrenSideEffects, String[] sideEffect) {
+			for (String s: childrenSideEffects) {
+				sideEffect[0] += s;
+			}
+			if (childrenTypes[0] != null && childrenTypes[0].equals(typeString) 
+					&& childrenTypes[1] != null && childrenTypes[1].equals(typeString)) {
+				return children[0] + ".equals(" + children[1] + ")";
+			}
+			return "(" + children[0] + "==" + children[1] + ")";
+		}
+	}, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (!(args.get(0).getClass() == Constant.class)) {
+				return null;
+			}
+			if (!(args.get(1).getClass() == Constant.class)) {
+				return null;
+			}
+			Constant arg0 = (Constant) args.get(0);
+			Constant arg1 = (Constant) args.get(1);
+			String sArg0 = arg0.getSymbol().toString();
+			String sArg1 = arg1.getSymbol().toString();
+			boolean result = false;
+			if (arg0.getType() == null || arg1.getType() == null) {
+				if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
+					result = Double.parseDouble(sArg0) == Double.parseDouble(sArg1);
+				} else {
+					result = Integer.parseInt(sArg0) == Integer.parseInt(sArg1);
+				}
+			}
+			if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
+				result = (Double.parseDouble(sArg0) == Double.parseDouble(sArg1));
+			} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
+				result = (Float.parseFloat(sArg0) == Float.parseFloat(sArg1));
+			} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
+				result = (Long.parseLong(sArg0) == Long.parseLong(sArg1));
+			} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
+				result = (Integer.parseInt(sArg0) == Integer.parseInt(sArg1));
+			} else if (arg0.getType().equals(typeString) || arg1.getType().equals(typeString)) {
+				result = sArg0.toString().equals(sArg1.toString());
+			}
+			if (result) {
+				return new Constant(true_);
+			} else {
+				return new Constant(false_);
+			}
+		}
+	});
+	public static final Symbol neq = new Symbol(Parser.NEQ, 2, Symbol.Type.INFIX, new Symbol.IImplGenerator() {
+		@Override
+		public String generate(Type type, Type[] childrenTypes, String[] children, String[] childrenSideEffects, String[] sideEffect) {
+			for (String s: childrenSideEffects) {
+				sideEffect[0] += s;
+			}
+			if (childrenTypes[0].equals(typeString) && childrenTypes[1].equals(typeString)) {
+				return "!" + children[0] + ".equals(" + children[1] + ")";
+			}
+			return "(" + children[0] + "!=" + children[1] + ")";
+		}
+	}, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (!(args.get(0).getClass() == Constant.class)) {
+				return null;
+			}
+			if (!(args.get(1).getClass() == Constant.class)) {
+				return null;
+			}
+			Constant arg0 = (Constant) args.get(0);
+			Constant arg1 = (Constant) args.get(1);
+			String sArg0 = arg0.getSymbol().toString();
+			String sArg1 = arg1.getSymbol().toString();
+			boolean result = false;
+			if (arg0.getType() == null || arg1.getType() == null) {
+				if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
+					result = Double.parseDouble(sArg0) != Double.parseDouble(sArg1);
+				} else {
+					result = Integer.parseInt(sArg0) != Integer.parseInt(sArg1);
+				}
+			}
+			if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
+				result = (Double.parseDouble(sArg0) != Double.parseDouble(sArg1));
+			} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
+				result = (Float.parseFloat(sArg0) != Float.parseFloat(sArg1));
+			} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
+				result = (Long.parseLong(sArg0) != Long.parseLong(sArg1));
+			} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
+				result = (Integer.parseInt(sArg0) != Integer.parseInt(sArg1));
+			} else if (arg0.getType().equals(typeString) || arg1.getType().equals(typeString)) {
+				result = !(sArg0.toString().equals(sArg1.toString()));
+			}
+			if (result) {
+				return new Constant(true_);
+			} else {
+				return new Constant(false_);
+			}
+		}
+	});
+	public static final Symbol gt = new Symbol(Parser.GT, 2, Symbol.Type.INFIX, ">", Symbol.Type.INFIX, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (!(args.get(0).getClass() == Constant.class)) {
+				return null;
+			}
+			if (!(args.get(1).getClass() == Constant.class)) {
+				return null;
+			}
+			Constant arg0 = (Constant) args.get(0);
+			Constant arg1 = (Constant) args.get(1);
+			String sArg0 = arg0.getSymbol().toString();
+			String sArg1 = arg1.getSymbol().toString();
+			boolean result = false;
+			if (arg0.getType() == null || arg1.getType() == null) {
+				if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
+					result = Double.parseDouble(sArg0) > Double.parseDouble(sArg1);
+				} else {
+					result = Integer.parseInt(sArg0) > Integer.parseInt(sArg1);
+				}
+			}
+			if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
+				result = (Double.parseDouble(sArg0) > Double.parseDouble(sArg1));
+			} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
+				result = (Float.parseFloat(sArg0) > Float.parseFloat(sArg1));
+			} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
+				result = (Long.parseLong(sArg0) > Long.parseLong(sArg1));
+			} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
+				result = (Integer.parseInt(sArg0) > Integer.parseInt(sArg1));
+			}
+			if (result) {
+				return new Constant(true_);
+			} else {
+				return new Constant(false_);
+			}
+		}
+	});
+	public static final Symbol lt = new Symbol(Parser.LT, 2, Symbol.Type.INFIX, "<", Symbol.Type.INFIX, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (!(args.get(0).getClass() == Constant.class)) {
+				return null;
+			}
+			if (!(args.get(1).getClass() == Constant.class)) {
+				return null;
+			}
+			Constant arg0 = (Constant) args.get(0);
+			Constant arg1 = (Constant) args.get(1);
+			String sArg0 = arg0.getSymbol().toString();
+			String sArg1 = arg1.getSymbol().toString();
+			boolean result = false;
+			if (arg0.getType() == null || arg1.getType() == null) {
+				if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
+					result = Double.parseDouble(sArg0) < Double.parseDouble(sArg1);
+				} else {
+					result = Integer.parseInt(sArg0) < Integer.parseInt(sArg1);
+				}
+			}
+			if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
+				result = (Double.parseDouble(sArg0) < Double.parseDouble(sArg1));
+			} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
+				result = (Float.parseFloat(sArg0) < Float.parseFloat(sArg1));
+			} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
+				result = (Long.parseLong(sArg0) < Long.parseLong(sArg1));
+			} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
+				result = (Integer.parseInt(sArg0) < Integer.parseInt(sArg1));
+			}
+			if (result) {
+				return new Constant(true_);
+			} else {
+				return new Constant(false_);
+			}
+		}
+	});
+	public static final Symbol ge = new Symbol(Parser.GE, 2, Symbol.Type.INFIX, ">=", Symbol.Type.INFIX, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (!(args.get(0).getClass() == Constant.class)) {
+				return null;
+			}
+			if (!(args.get(1).getClass() == Constant.class)) {
+				return null;
+			}
+			Constant arg0 = (Constant) args.get(0);
+			Constant arg1 = (Constant) args.get(1);
+			String sArg0 = arg0.getSymbol().toString();
+			String sArg1 = arg1.getSymbol().toString();
+			boolean result = false;
+			if (arg0.getType() == null || arg1.getType() == null) {
+				if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
+					result = Double.parseDouble(sArg0) >= Double.parseDouble(sArg1);
+				} else {
+					result = Integer.parseInt(sArg0) >= Integer.parseInt(sArg1);
+				}
+			}
+			if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
+				result = (Double.parseDouble(sArg0) >= Double.parseDouble(sArg1));
+			} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
+				result = (Float.parseFloat(sArg0) >= Float.parseFloat(sArg1));
+			} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
+				result = (Long.parseLong(sArg0) >= Long.parseLong(sArg1));
+			} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
+				result = (Integer.parseInt(sArg0) >= Integer.parseInt(sArg1));
+			}
+			if (result) {
+				return new Constant(true_);
+			} else {
+				return new Constant(false_);
+			}
+		}
+	});
+	public static final Symbol le = new Symbol(Parser.LE, 2, Symbol.Type.INFIX, "<=", Symbol.Type.INFIX, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (!(args.get(0).getClass() == Constant.class)) {
+				return null;
+			}
+			if (!(args.get(1).getClass() == Constant.class)) {
+				return null;
+			}
+			Constant arg0 = (Constant) args.get(0);
+			Constant arg1 = (Constant) args.get(1);
+			String sArg0 = arg0.getSymbol().toString();
+			String sArg1 = arg1.getSymbol().toString();
+			boolean result = false;
+			if (arg0.getType() == null || arg1.getType() == null) {
+				if (sArg0.contains(Parser.DOT) || sArg1.contains(Parser.DOT)) {
+					result = Double.parseDouble(sArg0) <= Double.parseDouble(sArg1);
+				} else {
+					result = Integer.parseInt(sArg0) <= Integer.parseInt(sArg1);
+				}
+			}
+			if (arg0.getType().equals(typeDouble) || arg1.getType().equals(typeDouble)) {
+				result = (Double.parseDouble(sArg0) <= Double.parseDouble(sArg1));
+			} else if (arg0.getType().equals(typeFloat) || arg1.getType().equals(typeFloat)) {
+				result = (Float.parseFloat(sArg0) <= Float.parseFloat(sArg1));
+			} else if (arg0.getType().equals(typeLong) || arg1.getType().equals(typeLong)) {
+				result = (Long.parseLong(sArg0) <= Long.parseLong(sArg1));
+			} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
+				result = (Integer.parseInt(sArg0) <= Integer.parseInt(sArg1));
+			}
+			if (result) {
+				return new Constant(true_);
+			} else {
+				return new Constant(false_);
+			}
+		}
+	});
+	public static final Symbol and = new Symbol(Parser.AND, 2, Symbol.Type.INFIX, "&&", Symbol.Type.INFIX, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (!(args.get(0).getClass() == Constant.class)) {
+				return null;
+			}
+			if (!(args.get(1).getClass() == Constant.class)) {
+				return null;
+			}
+			Constant arg0 = (Constant) args.get(0);
+			Constant arg1 = (Constant) args.get(1);
+			String sArg0 = arg0.getSymbol().toString();
+			String sArg1 = arg1.getSymbol().toString();
+			boolean result = false;
+			if (arg0.getType() == null || arg1.getType() == null) return null;
+			if (arg0.getType().equals(typeBoolean) || arg1.getType().equals(typeBoolean)) {
+				result = (Boolean.parseBoolean(sArg0) && Boolean.parseBoolean(sArg1));
+			}
+			if (result) {
+				return new Constant(true_);
+			} else {
+				return new Constant(false_);
+			}
+		}
+	});
+	public static final Symbol or = new Symbol(Parser.OR, 2, Symbol.Type.INFIX, "||", Symbol.Type.INFIX, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (!(args.get(0).getClass() == Constant.class)) {
+				return null;
+			}
+			if (!(args.get(1).getClass() == Constant.class)) {
+				return null;
+			}
+			Constant arg0 = (Constant) args.get(0);
+			Constant arg1 = (Constant) args.get(1);
+			String sArg0 = arg0.getSymbol().toString();
+			String sArg1 = arg1.getSymbol().toString();
+			boolean result = false;
+			if (arg0.getType() == null || arg1.getType() == null) return null;
+			if (arg0.getType().equals(typeBoolean) || arg1.getType().equals(typeBoolean)) {
+				result = (Boolean.parseBoolean(sArg0) || Boolean.parseBoolean(sArg1));
+			}
+			if (result) {
+				return new Constant(true_);
+			} else {
+				return new Constant(false_);
+			}
+		}
+	});
+	public static final Symbol neg = new Symbol(Parser.NEG, 1, Symbol.Type.PREFIX, "!", Symbol.Type.PREFIX, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (!(args.get(0).getClass() == Constant.class)) {
+				return null;
+			}
+			Constant arg0 = (Constant) args.get(0);
+			String sArg0 = arg0.getSymbol().toString();
+			boolean result = false;
+			if (arg0.getType() == null) return null;
+			if (arg0.getType().equals(typeBoolean)) {
+				result = !Boolean.parseBoolean(sArg0);
+			}
+			if (result) {
+				return new Constant(true_);
+			} else {
+				return new Constant(false_);
+			}
+		}
+	});
+	public static final Symbol cons = new Symbol("cons", 2, Symbol.Type.PREFIX, "($x,$y)->$x.add(0, $y)", Symbol.Type.LAMBDA_WITH_SIDE_EFFECT, new int[] {1, 0});
+	public static final Symbol append = new Symbol("append", 2, Symbol.Type.PREFIX, "add", Symbol.Type.METHOD_WITH_SIDE_EFFECT);		// Don't calculate here (Calculated in simulator).
+	public static final Symbol remove = new Symbol("remove", 2, Symbol.Type.PREFIX, "remove", Symbol.Type.METHOD_WITH_SIDE_EFFECT);		// Don't calculate here (Calculated in simulator).
+	public static final Symbol head = new Symbol("head", 1, Symbol.Type.PREFIX, "($x)->$x.get(0)", Symbol.Type.LAMBDA);
+	public static final Symbol tail = new Symbol("tail", 1, Symbol.Type.PREFIX, "($x)->$x.subList(1, $x.size())", Symbol.Type.LAMBDA);
+	public static final Symbol length = new Symbol("length", 1, Symbol.Type.PREFIX, "($x)->$x.size()", Symbol.Type.LAMBDA, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (args.get(0).getClass() == Constant.class && ((Constant) args.get(0)).getSymbol().equals(nil)) {
+				return new Constant("0", typeInt);
+			}
+			if (args.get(0) instanceof Term) {
+				Term term = (Term) args.get(0);
+				Type type = term.getType();
+				if (typeList.isAncestorOf(type)) {
+					int len = 0;
+					while (term.getSymbol().equals(DataConstraintModel.append)) {
+						len++;
+						term = (Term) term.getChild(0);
+					}
+					if (term instanceof ListTerm) {
+						len += ((ListTerm) term).getChildren().size();
+						return new Constant(Integer.toString(len), typeInt);
+					}
+				} else if (typeMap.isAncestorOf(type)) {
+					HashSet<String> keySet = new HashSet<>();
+					while (term.getSymbol().equals(DataConstraintModel.insert)) {
+						if (term.getChild(1).getClass() == Constant.class) {
+							keySet.add((String) ((Constant) term.getChild(1)).getValue());
+						}
+						term = (Term) term.getChild(0);
+					}
+					if (term instanceof MapTerm) {
+						keySet.addAll(((MapTerm) term).keySet());
+						return new Constant(Integer.toString(keySet.size()), typeInt);
+					}
+				} else if (typeJson.isAncestorOf(type)) {
+					HashSet<String> keySet = new HashSet<>();
+					while (term.getSymbol().equals(DataConstraintModel.addMember)) {
+						if (term.getChild(1).getClass() == Constant.class) {
+							keySet.add((String) ((Constant) term.getChild(1)).getValue());
+						}
+						term = (Term) term.getChild(0);
+					}
+					if (term instanceof JsonTerm) {
+						keySet.addAll(((JsonTerm) term).keySet());
+						return new Constant(Integer.toString(keySet.size()), typeInt);
+					}
+				}
+			}
+			return null;
+		}
+	});
+	public static final Symbol get = new Symbol("get", 2, Symbol.Type.PREFIX, "get", Symbol.Type.METHOD, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (args.get(1).getClass() == Constant.class && ((Constant) args.get(1)).getType().equals(typeInt)) {
+				int idx = Integer.parseInt(((Constant) args.get(1)).toString());
+				if (args.get(0) instanceof Term) {
+					Term term = (Term) args.get(0);
+					Type type = term.getType();
+					if (typeList.isAncestorOf(type)) {
+						Stack<Expression> appendedChldren = new Stack<>();
+						while (term.getSymbol().equals(DataConstraintModel.append)) {
+							if (!(term.getChild(0) instanceof Term)) {
+								return null;
+							}
+							appendedChldren.push(term.getChild(1));
+							term = (Term) term.getChild(0);
+						}
+						if (term instanceof ListTerm) {
+							ListTerm listTerm = (ListTerm) term.clone();
+							for (Expression child: appendedChldren) {
+								listTerm.append(child);
+							}
+							return listTerm.get(idx);
+						}
+					}
+				}
+			}
+			return null;
+		}
+	});
+	public static final Symbol set = new Symbol("set", 3, Symbol.Type.PREFIX, "set", Symbol.Type.METHOD_WITH_SIDE_EFFECT);				// Don't calculate here (Calculated in simulator).
+	public static final Symbol contains = new Symbol("contains", 2, Symbol.Type.PREFIX, new Symbol.IImplGenerator() {
+		@Override
+		public String generate(Type type, Type[] childrenTypes, String[] childrenImpl, String[] childrenSideEffects, String[] sideEffect) {
+			for (String s: childrenSideEffects) {
+				sideEffect[0] += s;
+			}
+			if (childrenTypes[0] != null && (typeMap.isAncestorOf(childrenTypes[0]) || typeJson.isAncestorOf(childrenTypes[0]))) {
+				return childrenImpl[0] + "." + "containsKey(" + childrenImpl[1] + ")";
+			}
+			return childrenImpl[0] + "." + "contains(" + childrenImpl[1] + ")";
+		}
+	}, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (args.get(0).getClass() == Constant.class && ((Constant) args.get(0)).getSymbol().equals(nil)) {
+				return new Constant(false_);
+			}
+			if (args.get(0) instanceof Term) {
+				Term term = (Term) args.get(0);
+				Type type = term.getType();
+				if (typeList.isAncestorOf(type)) {
+					while (term.getSymbol().equals(DataConstraintModel.append)) {
+						if (term.getChild(1).equals(args.get(1))) {
+							return new Constant(true_);
+						}
+						if (!(term.getChild(0) instanceof Term)) {
+							return new Constant(false_);
+						}
+						term = (Term) term.getChild(0);
+					}
+					if (term instanceof ListTerm) {
+						for (Expression element: term.getChildren()) {
+							if (element.equals(args.get(1))) {
+								return new Constant(true_);
+							}
+						}
+						return new Constant(false_);
+					}
+				} else if (typeMap.isAncestorOf(type)) {
+					while (term.getSymbol().equals(DataConstraintModel.insert)) {
+						if (term.getChild(1).equals(args.get(1))) {
+							return new Constant(true_);
+						}
+						if (!(term.getChild(0) instanceof Term)) {
+							return new Constant(false_);
+						}
+						term = (Term) term.getChild(0);
+					}
+					if (term instanceof MapTerm) {
+						String key;
+						if (args.get(1) instanceof Constant) {
+							key = (String) ((Constant) args.get(1)).getValue();
+						} else {
+							key = args.get(1).toString();
+						}
+						if (((MapTerm) term).keySet().contains(key)) {
+							return new Constant(true_);
+						}
+						return new Constant(false_);
+					}
+				} else if (typeJson.isAncestorOf(type)) {
+					while (term.getSymbol().equals(DataConstraintModel.addMember)) {
+						if (term.getChild(1).equals(args.get(1))) {
+							return new Constant(true_);
+						}
+						if (!(term.getChild(0) instanceof Term)) {
+							return new Constant(false_);
+						}
+						term = (Term) term.getChild(0);
+					}
+					if (term instanceof JsonTerm) {
+						String key;
+						if (args.get(1) instanceof Constant) {
+							key = (String) ((Constant) args.get(1)).getValue();
+						} else {
+							key = args.get(1).toString();
+						}
+						if (((JsonTerm) term).keySet().contains(key)) {
+							return new Constant(true_);
+						}
+						return new Constant(false_);
+					}
+				}
+			}
+			return null;
+		}
+	});
+	public static final Symbol indexOf = new Symbol("indexOf", 2, Symbol.Type.PREFIX, "indexOf", Symbol.Type.METHOD, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (args.get(0) instanceof Term) {
+				Term term = (Term) args.get(0);
+				Type type = term.getType();
+				if (typeList.isAncestorOf(type)) {
+					Stack<Expression> appendedChldren = new Stack<>();
+					while (term.getSymbol().equals(DataConstraintModel.append)) {
+						if (!(term.getChild(0) instanceof Term)) {
+							return null;
+						}
+						appendedChldren.push(term.getChild(1));
+						term = (Term) term.getChild(0);
+					}
+					if (term instanceof ListTerm) {
+						int idx = 0;
+						ListTerm listTerm = (ListTerm) term;
+						for (Expression child: listTerm.getChildren()) {
+							if (child.equals(args.get(1))) {
+								return new Constant(Integer.toString(idx), typeInt);
+							}
+							idx++;
+						}
+						for (Expression child: appendedChldren) {
+							if (child.equals(args.get(1))) {
+								return new Constant(Integer.toString(idx), typeInt);
+							}
+							idx++;
+						}
+					}
+				}
+			}
+			return null;
+		}
+	});
+	public static final Symbol nil = new Symbol("nil", 0, Symbol.Type.PREFIX, new Symbol.IImplGenerator() {
+		final int count[] = {0};
+		@Override
+		public String generate(Type type, Type[] childrenTypes, String[] children, String[] childrenSideEffects, String[] sideEffect) {
+			String compType = "";
+			if (type != null) {
+				String interfaceType = type.getInterfaceTypeName();
+				if (interfaceType.contains("<")) {
+					compType = interfaceType.substring(interfaceType.indexOf("<") + 1, interfaceType.lastIndexOf(">"));
+				}
+				String implType = type.getImplementationTypeName();
+				if (implType.indexOf('<') >= 0) {
+					implType = implType.substring(0, implType.indexOf('<'));
+				}
+				if (sideEffect == null) {
+					return "new " + implType + "<>()";
+				} else {
+					String temp = "temp_nil" + count[0];
+					if (sideEffect[0] == null) {
+						sideEffect[0] = "";
+					}
+					sideEffect[0] += interfaceType + " " + temp + " = " + "new " + implType + "<" + compType + ">();\n";
+					count[0]++;
+					return temp;
+				}
+			}			
+			return "new ArrayList<" + compType + ">()";
+		}
+	}, true);
+	public static final Symbol null_ = new Symbol("null", 0, Symbol.Type.PREFIX, "null", Symbol.Type.PREFIX);
+	public static final Symbol true_ = new Symbol("true", 0, Symbol.Type.PREFIX, "true", Symbol.Type.PREFIX);
+	public static final Symbol false_ = new Symbol("false", 0, Symbol.Type.PREFIX, "false", Symbol.Type.PREFIX);
+	public static final Symbol cond = new Symbol("if", 3, Symbol.Type.PREFIX, new Symbol.IImplGenerator() {
+		final int count[] = {0};
+		@Override
+		public String generate(Type type, Type[] childrenTypes, String[] childrenImpl, String[] childrenSideEffects, String[] sideEffect) {
+			String temp = "temp_if" + count[0];
+			String impl = ""; 
+			
+			impl += type.getInterfaceTypeName() + " " + temp + ";\n";
+			if (childrenSideEffects[0] != null && childrenSideEffects[0].length() > 0) impl += childrenSideEffects[0];
+			impl += "if (" + childrenImpl[0] + ") {\n";
+			if (childrenSideEffects[1] != null && childrenSideEffects[1].length() > 0) impl += "\t" + childrenSideEffects[1];
+			impl += "\t" + temp + " = " + childrenImpl[1] + ";\n";
+			impl += "} else {\n";
+			if (childrenSideEffects[2] != null && childrenSideEffects[2].length() > 0) impl += "\t" + childrenSideEffects[2];
+			impl += "\t" + temp + " = " + childrenImpl[2] + ";\n";
+			impl += "}\n";
+			
+			sideEffect[0] += impl;
+			
+			count[0]++;
+			return temp;
+		}
+	}, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (!(args.get(0).getClass() == Constant.class)) return null;
+			if (((Constant) args.get(0)).getSymbol().equals(true_)) {
+				return args.get(1);
+			} else if (((Constant) args.get(0)).getSymbol().equals(false_)) {
+				return args.get(2);
+			}
+			return null;
+		}
+	});
+	public static final Symbol pair = new Symbol("pair", -1, Symbol.Type.PREFIX, new Symbol.IImplGenerator() {
+		@Override
+		public String generate(Type type, Type[] childrenTypes, String[] childrenImpl, String[] childrenSideEffects, String[] sideEffect) {
+			for (String s: childrenSideEffects) {
+				sideEffect[0] += s;
+			}
+			String impl = "new Pair<>(" + childrenImpl[0] + "," + childrenImpl[1] + ")";
+			return impl;
+		}
+	});
+	public static final Symbol tuple = new Symbol("tuple", -1, Symbol.Type.PREFIX, new Symbol.IImplGenerator() {
+		@Override
+		public String generate(Type type, Type[] childrenTypes, String[] childrenImpl, String[] childrenSideEffects, String[] sideEffect) {
+			for (String s: childrenSideEffects) {
+				sideEffect[0] += s;
+			}
+			String impl = "new AbstractMap.SimpleEntry<>(" + childrenImpl[0] + "$x)";
+			for (int i = 1; i < childrenImpl.length - 1; i++) {
+				impl = impl.replace("$x", ", new AbstractMap.SimpleEntry<>(" + childrenImpl[i] + "$x)");
+			}
+			impl = impl.replace("$x", ", " + childrenImpl[childrenImpl.length - 1]);
+			return impl;
+		}
+	});
+	public static final Symbol fst = new Symbol("fst", 1, Symbol.Type.PREFIX, "getKey", Symbol.Type.METHOD);
+	public static final Symbol snd = new Symbol("snd", 1, Symbol.Type.PREFIX, "getValue", Symbol.Type.METHOD);
+	public static final Symbol left = new Symbol("left", 1, Symbol.Type.PREFIX, "getLeft", Symbol.Type.METHOD);
+	public static final Symbol right = new Symbol("right", 1, Symbol.Type.PREFIX, "getRight", Symbol.Type.METHOD);
+	public static final Symbol insert = new Symbol("insert", 3, Symbol.Type.PREFIX, "put", Symbol.Type.METHOD_WITH_SIDE_EFFECT);		// Don't calculate here (Calculated in simulator).
+	public static final Symbol delete = new Symbol("delete", 2, Symbol.Type.PREFIX, "remove", Symbol.Type.METHOD_WITH_SIDE_EFFECT);		// Don't calculate here (Calculated in simulator).
+	public static final Symbol lookup = new Symbol("lookup", 2, Symbol.Type.PREFIX, "get", Symbol.Type.METHOD, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (args.get(1).getClass() == Constant.class && ((Constant) args.get(1)).getType().equals(typeString)) {
+				String key = (String) ((Constant) args.get(1)).getValue();
+				if (args.get(0) instanceof Term) {
+					Term term = (Term) args.get(0);
+					Type type = term.getType();
+					if (typeMap.isAncestorOf(type)) {
+						Stack<Map.Entry<Expression, Expression>> appendedChldren = new Stack<>();
+						while (term.getSymbol().equals(DataConstraintModel.insert)) {
+							if (!(term.getChild(0) instanceof Term)) {
+								return null;
+							}
+							appendedChldren.push(new AbstractMap.SimpleEntry<>(term.getChild(0), term.getChild(1)));
+							term = (Term) term.getChild(0);
+						}
+						if (term instanceof MapTerm) {
+							MapTerm mapTerm = (MapTerm) term.clone();
+							for (Map.Entry<Expression, Expression> childEnt: appendedChldren) {
+								if (childEnt.getKey().getClass() == Constant.class)
+								mapTerm.insert((String) ((Constant) childEnt.getKey()).getValue(), childEnt.getValue());
+							}
+							return mapTerm.get(key);
+						}
+					}
+				}
+			}
+			return null;
+		}
+	});
+	public static final Symbol addMember = new Symbol("addMember", 3, Symbol.Type.PREFIX, "put", Symbol.Type.METHOD_WITH_SIDE_EFFECT);
+	public static final Symbol dot = new Symbol(Parser.DOT, 2, Symbol.Type.INFIX, "get", Symbol.Type.METHOD);
+	public static final Symbol dotParam = new Symbol(Parser.DOT, 2, Symbol.Type.INFIX, "get", Symbol.Type.METHOD);
+	public static final Symbol pi = new Symbol("PI", 0, Symbol.Type.PREFIX, "Math.PI", Symbol.Type.PREFIX, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			return new Constant(Double.toString(Math.PI), typeDouble);
+		}});
+	public static final Symbol E = new Symbol("E", 0, Symbol.Type.PREFIX, "Math.E", Symbol.Type.PREFIX, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			return new Constant(Double.toString(Math.E), typeDouble);
+		}});
+	public static final Symbol sqrt = new Symbol("sqrt", 1, Symbol.Type.PREFIX, "Math.sqrt", Symbol.Type.PREFIX, new Symbol.ICalculator() {
+		@Override
+		public Expression calculate(List<Expression> args) {
+			if (args.get(0).getClass() == Constant.class) {
+				if (((Constant) args.get(0)).getType().equals(typeDouble)) {
+					return new Constant(Double.toString(Math.sqrt(Double.parseDouble((String) ((Constant) args.get(0)).getValue()))), typeDouble);
+				} else if (((Constant) args.get(0)).getType().equals(typeFloat)) {
+					return new Constant(Float.toString((float) Math.sqrt(Float.parseFloat((String) ((Constant) args.get(0)).getValue()))), typeFloat);
+				}
+			}
+			return null;
+		}});
+	public static final Symbol sin = new Symbol("sin", 1, Symbol.Type.PREFIX, "Math.sin", Symbol.Type.PREFIX);
+	public static final Symbol cos = new Symbol("cos", 1, Symbol.Type.PREFIX, "Math.cos", Symbol.Type.PREFIX);
+	public static final Symbol tan = new Symbol("tan", 1, Symbol.Type.PREFIX, "Math.tan", Symbol.Type.PREFIX);
+	public static final Symbol asin = new Symbol("asin", 1, Symbol.Type.PREFIX, "Math.asin", Symbol.Type.PREFIX);
+	public static final Symbol acos = new Symbol("acos", 1, Symbol.Type.PREFIX, "Math.acos", Symbol.Type.PREFIX);
+	public static final Symbol atan = new Symbol("atan", 1, Symbol.Type.PREFIX, "Math.atan", Symbol.Type.PREFIX);
+	public static final Symbol pow = new Symbol("pow", 2, Symbol.Type.PREFIX, "Math.pow", Symbol.Type.PREFIX);
+	public static final Symbol exp = new Symbol("exp", 1, Symbol.Type.PREFIX, "Math.exp", Symbol.Type.PREFIX);
+	public static final Symbol log = new Symbol("log", 1, Symbol.Type.PREFIX, "Math.log", Symbol.Type.PREFIX);
+	public static final Symbol abs = new Symbol("abs", 1, Symbol.Type.PREFIX, "Math.abs", Symbol.Type.PREFIX);
+		
+	static {
+		add.setInverses(new Symbol[] {sub, sub});
+		mul.setInverses(new Symbol[] {div, div});
+		sub.setInverses(new Symbol[] {add});
+		div.setInverses(new Symbol[] {mul});
+		minus.setInverses(new Symbol[] {minus});
+		mod.setSignature(new Type[] {typeInt, null, null});
+		eq.setSignature(new Type[] {typeBoolean, null, null});
+		neq.setSignature(new Type[] {typeBoolean, null, null});
+		gt.setSignature(new Type[] {typeBoolean, null, null});
+		lt.setSignature(new Type[] {typeBoolean, null, null});
+		ge.setSignature(new Type[] {typeBoolean, null, null});
+		le.setSignature(new Type[] {typeBoolean, null, null});
+		and.setSignature(new Type[] {typeBoolean, typeBoolean, typeBoolean});
+		or.setSignature(new Type[] {typeBoolean, typeBoolean, typeBoolean});
+		neg.setSignature(new Type[] {typeBoolean, typeBoolean});
+		cons.setInverses(new Symbol[] {head, tail});
+		cons.setSignature(new Type[] {typeList, null, typeList});
+		append.setSignature(new Type[] {typeList, typeList, null});
+		remove.setSignature(new Type[] {typeList, typeList, typeInt});
+		head.setSignature(new Type[] {null, typeList});
+		tail.setSignature(new Type[] {typeList, typeList});
+		contains.setSignature(new Type[] {typeBoolean, null, null});
+		indexOf.setSignature(new Type[] {typeInt, typeList, null});
+		length.setSignature(new Type[] {typeInt, null});
+		get.setSignature(new Type[] {null, typeList, typeInt});
+		set.setSignature(new Type[] {typeList, typeList, typeInt, null});
+		null_.setSignature(new Type[] {null});
+		true_.setSignature(new Type[] {typeBoolean});
+		false_.setSignature(new Type[] {typeBoolean});
+		pair.setSignature(new Type[] {typePair,null,null});
+		pair.setInverses(new Symbol[] {left, right});
+		left.setSignature(new Type[] {null, typePair});
+		right.setSignature(new Type[] {null, typePair});
+		tuple.setSignature(new Type[] {typeTuple, null, null});
+		tuple.setInverses(new Symbol[] {fst, snd});
+		fst.setSignature(new Type[] {null, typeTuple});
+		fst.setInverses(new Symbol[] {new LambdaAbstraction(new Variable("x"), new Term(tuple, new Expression[] {new Variable("x"), new Variable("y")}))});
+		snd.setSignature(new Type[] {null, typeTuple});
+		snd.setInverses(new Symbol[] {new LambdaAbstraction(new Variable("y"), new Term(tuple, new Expression[] {new Variable("x"), new Variable("y")}))});
+		insert.setSignature(new Type[] {typeMap, typeMap, null, null});
+		delete.setSignature(new Type[] {typeMap, typeMap, null});
+		lookup.setSignature(new Type[] {null, typeMap, null});
+		addMember.setSignature(new Type[] {typeJson, typeJson, typeString, null});
+		dot.setSignature(new Type[] {null, typeJson, typeString});
+		dotParam.setSignature(new Type[] {null, null, null});
+		pi.setSignature(new Type[] {typeDouble});
+		E.setSignature(new Type[] {typeDouble});
+		sqrt.setSignature(new Type[] {typeDouble, typeDouble});
+		sin.setSignature(new Type[] {typeDouble, typeDouble});
+		cos.setSignature(new Type[] {typeDouble, typeDouble});
+		tan.setSignature(new Type[] {typeDouble, typeDouble});
+		asin.setSignature(new Type[] {typeDouble, typeDouble});
+		asin.setInverses(new Symbol[] {sin});
+		acos.setSignature(new Type[] {typeDouble, typeDouble});
+		acos.setInverses(new Symbol[] {cos});
+		atan.setSignature(new Type[] {typeDouble, typeDouble});
+		atan.setInverses(new Symbol[] {tan});
+		pow.setSignature(new Type[] {typeDouble, typeDouble, typeDouble});
+		exp.setSignature(new Type[] {typeDouble, typeDouble});
+		exp.setInverses(new Symbol[] {log});
+		log.setSignature(new Type[] {typeDouble, typeDouble});
+		log.setInverses(new Symbol[] {exp});
+		abs.setSignature(new Type[] {typeDouble, typeDouble});
+	}
+	
+	public DataConstraintModel() {
+		resourcePaths = new ArrayList<>();
+		resourceHierarchies = new HashMap<>();
+		channels = new HashMap<>();
+		inputChannels = new HashMap<>();
+		types = new HashMap<>();
+		addType(typeInt);
+		addType(typeLong);
+		addType(typeFloat);
+		addType(typeDouble);
+		addType(typeBoolean);
+		addType(typeString);
+		addType(typeList);
+		addType(typePair);
+		addType(typeTuple);
+		addType(typeMap);
+		addType(typeJson);
+		symbols = new HashMap<>();
+		addSymbol(add);
+		addSymbol(mul);
+		addSymbol(sub);
+		addSymbol(div);
+		addSymbol(minus);
+		addSymbol(mod);
+		addSymbol(eq);
+		addSymbol(neq);
+		addSymbol(gt);
+		addSymbol(lt);
+		addSymbol(ge);
+		addSymbol(le);
+		addSymbol(and);
+		addSymbol(or);
+		addSymbol(neg);
+		addSymbol(cons);
+		addSymbol(append);
+		addSymbol(remove);
+		addSymbol(head);
+		addSymbol(tail);
+		addSymbol(length);
+		addSymbol(contains);
+		addSymbol(indexOf);
+		addSymbol(get);
+		addSymbol(set);
+		addSymbol(cond);
+		addSymbol(nil);
+		addSymbol(null_);
+		addSymbol(true_);
+		addSymbol(false_);
+		addSymbol(pair);
+		addSymbol(left);
+		addSymbol(right);
+		addSymbol(tuple);
+		addSymbol(fst);
+		addSymbol(snd);
+		addSymbol(insert);
+		addSymbol(delete);
+		addSymbol(lookup);
+		addSymbol(addMember);
+		addSymbol(dot);
+		addSymbol(dotParam);
+		addSymbol(pi);
+		addSymbol(E);
+		addSymbol(sqrt);
+		addSymbol(sin);
+		addSymbol(cos);
+		addSymbol(tan);
+		addSymbol(asin);
+		addSymbol(acos);
+		addSymbol(atan);
+		addSymbol(pow);
+		addSymbol(exp);
+		addSymbol(log);
+		addSymbol(abs);
+	}
+	
+	public Collection<ResourceHierarchy> getResourceHierarchies() {
+		return resourceHierarchies.values();
+	}
+	
+	public ResourceHierarchy getResourceHierarchy(String hierarchy) {
+		return resourceHierarchies.get(hierarchy);
+	}
+	
+	public ResourceHierarchy getOrPutResourceHierarchy(ResourceHierarchy resourceHierarchy) {
+		String hierarchy = resourceHierarchy.toString();
+		if (resourceHierarchies.get(hierarchy) != null) {
+			return resourceHierarchies.get(hierarchy);
+		}
+		resourceHierarchies.put(hierarchy, resourceHierarchy);
+		return resourceHierarchy;
+	}
+	
+	public List<ResourcePath> getResourcePaths() {
+		return resourcePaths;
+	}
+	
+	public void addResourcePath(ResourcePath resourcePath) {
+		resourcePaths.add(resourcePath);
+		ResourceHierarchy childHierarchy = null;
+		ResourceHierarchy hierarchy = null;
+		do {
+			hierarchy = resourcePath.getResourceHierarchy();
+			if (hierarchy != null && resourceHierarchies.get(hierarchy.toString()) == null) {
+				resourceHierarchies.put(hierarchy.toString(), hierarchy);				
+			} else {
+				hierarchy = resourceHierarchies.get(hierarchy.toString());
+				resourcePath.setResourceHierarchy(hierarchy);
+				if (childHierarchy != null) {
+					childHierarchy.setParent(hierarchy);
+				}
+			}
+			resourcePath = resourcePath.getParent();
+			childHierarchy = hierarchy;
+		} while (resourcePath != null);
+	}
+	
+	public void setResourcePaths(List<ResourcePath> resourcePaths) {
+		this.resourcePaths = resourcePaths;
+	}
+	
+	public ResourcePath getResourcePath(String path) {
+		for (ResourcePath resourcePath: resourcePaths) {
+			if (resourcePath.toString().equals(path)) return resourcePath;
+		}
+		return null;
+	}
+	
+	public void removeResourcePath(String path) {
+		ResourcePath resourcePath = getResourcePath(path);
+		if (resourcePath == null) return;
+		resourcePaths.remove(resourcePath);
+		for (Channel ch: channels.values()) {
+			ch.removeChannelMember(resourcePath);
+		}
+		for (Channel ch: inputChannels.values()) {
+			ch.removeChannelMember(resourcePath);
+		}
+	}
+
+	public Collection<Channel> getChannels() {
+		return channels.values();
+	}
+		
+	public Channel getChannel(String channelName) {
+		return channels.get(channelName);
+	}
+	
+	public void setChannels(HashMap<String, Channel> channels) {
+		this.channels = channels;
+	}
+	
+	public void addChannel(Channel channel) {
+		channels.put(channel.getChannelName(), channel);
+	}
+	
+	public void removeChannel(String channelName) {
+		channels.remove(channelName);
+	}
+	
+	public Collection<Channel> getInputChannels() {
+		return inputChannels.values();
+	}
+	
+	public Channel getInputChannel(String channelName) {
+		return inputChannels.get(channelName);
+	}
+	
+	public void setInputChannels(HashMap<String, Channel> inputChannels) {
+		this.inputChannels = inputChannels;
+	}
+	
+	public void addInputChannel(Channel inputChannel) {
+		inputChannels.put(inputChannel.getChannelName(), inputChannel);
+	}
+	
+	public void removeInputChannel(String inputChannelName) {
+		inputChannels.remove(inputChannelName);
+	}
+	
+	public void addType(Type type) {
+		types.put(type.getTypeName(), type);
+	}
+	
+	public Type getType(String name) {
+		return types.get(name);
+	}
+	
+	public void addSymbol(Symbol symbol) {
+		symbols.put(symbol.getName(), symbol);
+	}
+	
+	public Symbol getSymbol(String name) {
+		return symbols.get(name);
+	}
+	
+	public static String getWrapperType(Type type) {
+		if (type == typeInt) {
+			return "Integer";
+		} else if (type == typeLong) {
+			return "Long";
+		} else if (type == typeFloat) {
+			return "Float";
+		} else if (type == typeDouble) {
+			return "Double";
+		} else if (type == typeBoolean) {
+			return "Boolean";
+		}
+		return null;
+	}
+	
+	public boolean isPrimitiveType(Type type) {
+		if (type == typeInt 
+			|| type == typeLong
+			|| type == typeFloat
+			|| type == typeDouble
+			|| type == typeBoolean) {
+			return true;
+		}
+		return false;
+	}
+
+	public static boolean isListType(Type type) {
+		return typeList.isAncestorOf(type);
+	}
+
+	public static String getDefaultValue(Type type) {
+		if (type == typeInt) {
+			return "0";
+		} else if (type == typeLong) {
+			return "0L";
+		} else if (type == typeFloat) {
+			return "0.0f";
+		} else if (type == typeDouble) {
+			return "0.0";
+		} else if (type == typeBoolean) {
+			return "false";
+		} else if (type == typeString) {
+			return "\"\"";
+		}
+		return "new " + type.getImplementationTypeName() + "()";
+	}
+	
+	public static Expression getDefaultValueExpression(Type type) {
+		if (type == typeInt) {
+			return new Constant("0", typeInt);
+		} else if (type == typeLong) {
+			return new Constant("0L", typeLong);
+		} else if (type == typeFloat) {
+			return new Constant("0.0f", typeFloat);
+		} else if (type == typeDouble) {
+			return new Constant("0.0", typeDouble);
+		} else if (type == typeBoolean) {
+			return new Constant(false_);
+		} else if (type == typeString) {
+			return new Constant("", typeString);
+		} else if (type.isAncestorOf(typeList)) {
+			return new ListTerm();
+		} else if (type.isAncestorOf(typeMap)) {
+			return new MapTerm();
+		} else if (type.isAncestorOf(typeJson)) {
+			return new JsonTerm();
+		}
+		return null;
+	}
+	
+	@Override
+	public String toString() {
+		String out = "";
+		for (Channel channel: inputChannels.values()) {
+			out += channel.toString();
+		}
+		for (Channel channel: channels.values()) {
+			out += channel.toString();
+		}
+		return out;
+	}
+	
+	public String getSourceText() {
+		String out = "";
+		String init = "";
+		for (ResourceHierarchy resource: resourceHierarchies.values()) {
+			String initializer = resource.getInitText();
+			if (initializer != null) {
+				init += resource.toString() + " := " + initializer + "\n";
+			}
+		}
+		if (init.length() > 0) {
+			out += "init {\n" + init + "}\n";
+		}
+		for (Channel channel: inputChannels.values()) {
+			out += channel.getSourceText();
+		}
+		for (Channel channel: channels.values()) {
+			out += channel.getSourceText();
+		}
+		return out;
+	}
+}
diff --git a/AlgebraicDataflowArchitectureModel/src/simulator/Simulator.java b/AlgebraicDataflowArchitectureModel/src/simulator/Simulator.java
index 2093291..d14be4d 100644
--- a/AlgebraicDataflowArchitectureModel/src/simulator/Simulator.java
+++ b/AlgebraicDataflowArchitectureModel/src/simulator/Simulator.java
@@ -18,6 +18,7 @@
 import models.algebra.Variable;
 import models.dataConstraintModel.Channel;
 import models.dataConstraintModel.ChannelMember;
+import models.dataConstraintModel.DataConstraintModel;
 import models.dataConstraintModel.ResourceHierarchy;
 import models.dataConstraintModel.ResourcePath;
 import models.dataConstraintModel.Selector;
@@ -59,6 +60,11 @@
 						initialValue = ((Term) initialValue).reduce();
 					}
 					curState.updateResourceState(resource.getResourceIdentifier(), null, null, initialValue);
+				} else if (res.getResourceStateType() != null) {
+					initialValue = DataConstraintModel.getDefaultValueExpression(res.getResourceStateType());
+					if (initialValue != null) {
+						curState.updateResourceState(resource.getResourceIdentifier(), null, null, initialValue);
+					}
 				}
 			}
 		}
@@ -195,7 +201,7 @@
 				Expression nextResState = null;
 				outTarget[0] = out;
 				outResVar[0] = new Variable(channel.getChannelName() + "$" + out.getResource().toString() + "$this");		// A special variable to represent the current state of each output resource.
-				if (!event.isInput()) {
+				if (!event.isInput() || event.getMessage() instanceof Variable) {
 					nextResState = channel.deriveUpdateExpressionOf(out, resouceStateAccessor).getKey();
 				} else {
 					nextResState = channel.deriveUpdateExpressionOf(out, (Term) event.getMessage(), resouceStateAccessor);