reduce1 regel

notizen/stf/Notes

@@ -32,6 +32,9 @@ Instanceof wird verwendet da:
 	
 Gilt reduce für alle Typen oder nur für simple und tphs? (Vermutlich nur s und tph sonst bräuchte  man keine upLow regel)
 
++++++++++++++++++++++++++++++++++++++++++++++++
+
+- Typen sind anhand ihres identifiers durchgängig identifizierbar
 
 EED UP
 	- Anwendungsreihenfolge der Regeln (wahrscheinlichste zuerst, evtl ist nach regel 1 regel 2 nie möglich etc...)

src/de/dhbwstuttgart/typeinference/unify/interfaces/IFiniteClosure.java

@@ -28,4 +28,8 @@ public interface IFiniteClosure {
 	public boolean isInGrArg(Type grArgT, Type t);
 	
 	public boolean isInSmArg(Type smArgT, Type t);
+	
+	public Set<Type> smaller(String typeName);
+	
+	public Type getType(String typeName);
 }

src/de/dhbwstuttgart/typeinference/unify/interfaces/IRuleSet.java

@@ -1,17 +1,20 @@
 package de.dhbwstuttgart.typeinference.unify.interfaces;
 
+import java.util.Optional;
+import java.util.Set;
+
 import de.dhbwstuttgart.typinference.unify.model.MPair;
 
 public interface IRuleSet {
 	
-	public boolean reduceUp(MPair pair);
+	public Optional<MPair> reduceUp(MPair pair);
-	public boolean reduceLow(MPair pair);
+	public Optional<MPair> reduceLow(MPair pair);
-	public boolean reduceUpLow(MPair pair);
+	public Optional<MPair> reduceUpLow(MPair pair);
-	public boolean reduceExt(MPair pair);
+	public Optional<Set<MPair>> reduceExt(MPair pair);
-	public boolean reduceSup(MPair pair);
+	public Optional<Set<MPair>> reduceSup(MPair pair);
-	public boolean reduceEq(MPair pair);
+	public Optional<Set<MPair>> reduceEq(MPair pair);
-	public boolean reduce1(MPair pair);
+	public Optional<Set<MPair>> reduce1(MPair pair);
-	public boolean reduce2(MPair pair);
+	public Optional<Set<MPair>> reduce2(MPair pair);
 	
 	public boolean erase1(MPair pair);
 	public boolean erase2(MPair pair);

src/de/dhbwstuttgart/typeinference/unifynew/RuleSet.java

@@ -1,5 +1,10 @@
 package de.dhbwstuttgart.typeinference.unifynew;
 
+import java.util.HashSet;
+import java.util.Optional;
+import java.util.Set;
+
+import junit.framework.Assert;
 import de.dhbwstuttgart.typeinference.unify.interfaces.IFiniteClosure;
 import de.dhbwstuttgart.typeinference.unify.interfaces.IRuleSet;
 import de.dhbwstuttgart.typinference.unify.model.ExtendsType;
@@ -19,85 +24,108 @@ public class RuleSet implements IRuleSet{
 	}
 	
 	@Override
-	public boolean reduceUp(MPair pair) {
+	public Optional<MPair> reduceUp(MPair pair) {
 		if(pair.getPairOp() != PairOperator.SMALLERDOT)
-			return false;
+			return Optional.empty();
 		
 		Type rhsType = pair.getRhsType();
 		if(!(rhsType instanceof SuperType))
-			return false;
+			return Optional.empty();
 		
 		Type lhsType = pair.getLhsType();
 		if(!(lhsType instanceof SimpleType) && !(lhsType instanceof PlaceholderType))
-			return false;
+			return Optional.empty();
 		
-		pair.setRhsType(((SuperType) rhsType).GetSuperedType());
+		return Optional.of(new MPair(lhsType, ((SuperType) rhsType).GetSuperedType()));
-		return true;
 	}
 
 	@Override
-	public boolean reduceLow(MPair pair) {
+	public Optional<MPair> reduceLow(MPair pair) {
 		if(pair.getPairOp() != PairOperator.SMALLERDOT)
-			return false;
+			return Optional.empty();
 		
 		Type lhsType = pair.getLhsType();
 		if(!(lhsType instanceof ExtendsType))
-			return false;
+			return Optional.empty();
 		
 		Type rhsType = pair.getRhsType();
 		if(!(rhsType instanceof SimpleType) && !(rhsType instanceof PlaceholderType))
-			return false;
+			return Optional.empty();
-		
+
-		pair.setLhsType(((ExtendsType) lhsType).GetExtendedType());
+		return Optional.of(new MPair(((ExtendsType) lhsType).GetExtendedType(), rhsType));
-		return true;
 	}
 
 	@Override
-	public boolean reduceUpLow(MPair pair) {
+	public Optional<MPair> reduceUpLow(MPair pair) {
 		if(pair.getPairOp() != PairOperator.SMALLERDOT)
-			return false;
+			return Optional.empty();
 		
 		Type lhsType = pair.getLhsType();
 		if(!(lhsType instanceof ExtendsType))
-			return false;
+			return Optional.empty();
 		
 		Type rhsType = pair.getRhsType();
 		if(!(rhsType instanceof SuperType))
-			return false;
+			return Optional.empty();
 		
-		pair.setLhsType(((ExtendsType) lhsType).GetExtendedType());
+		return Optional.of(new MPair(((ExtendsType) lhsType).GetExtendedType(),((SuperType) rhsType).GetSuperedType()));
-		pair.setRhsType(((SuperType) rhsType).GetSuperedType());
-		return true;
 	}
 
 	@Override
-	public boolean reduceExt(MPair pair) {
+	public Optional<Set<MPair>> reduceExt(MPair pair) {
-		// TODO Auto-generated method stub
+		if(pair.getPairOp() != PairOperator.SMALLERDOTWC)
-		return false;
+			return Optional.empty();
+		
+		
+		return null;
 	}
 
 	@Override
-	public boolean reduceSup(MPair pair) {
+	public Optional<Set<MPair>> reduceSup(MPair pair) {
 		// TODO Auto-generated method stub
-		return false;
+		return null;
 	}
 
 	@Override
-	public boolean reduceEq(MPair pair) {
+	public Optional<Set<MPair>> reduceEq(MPair pair) {
 		// TODO Auto-generated method stub
-		return false;
+		return null;
 	}
 
 	@Override
-	public boolean reduce1(MPair pair) {
+	public Optional<Set<MPair>> reduce1(MPair pair) {
-		// TODO Auto-generated method stub
+		if(pair.getPairOp() != PairOperator.SMALLERDOT)
-		return false;
+			return Optional.empty();
+		
+		Type lhsType = pair.getLhsType();
+		if(!(lhsType instanceof SimpleType))
+			return Optional.empty();
+		
+		Type rhsType = pair.getRhsType();
+		if(!(rhsType instanceof SimpleType))
+			return Optional.empty();
+		
+		SimpleType lhsSType = (SimpleType) lhsType;
+		SimpleType rhsSType = (SimpleType) rhsType;
+		
+		if(lhsSType.getTypeArgs().length == 0 || rhsSType.getTypeArgs().length == 0 || lhsSType.getTypeArgs() != rhsSType.getTypeArgs())
+			return Optional.empty();
+		
+		int[] pi = pi(lhsSType, rhsSType);
+		Type[] rhsTypeArgs = rhsType.getTypeArgs();
+		Type[] lhsTypeArgs = lhsType.getTypeArgs();
+		Set<MPair> result = new HashSet<>();
+		
+		for(int rhsIdx = 0; rhsIdx < rhsTypeArgs.length; rhsIdx++)
+			result.add(new MPair(lhsTypeArgs[pi[rhsIdx]], rhsTypeArgs[rhsIdx]));
+		
+		return Optional.of(result);
 	}
 
 	@Override
-	public boolean reduce2(MPair pair) {
+	public Optional<Set<MPair>> reduce2(MPair pair) {
 		// TODO Auto-generated method stub
-		return false;
+		return null;
 	}
 
 	@Override
@@ -164,4 +192,47 @@ public class RuleSet implements IRuleSet{
 		return null;
 	}
 
+	/**
+	 * Finds the permutation pi of the type arguments of two types based on the finite closure
+	 * @param C The type which arguments are permuted
+	 * @param D The other type
+	 * @return An array containing the values of pi for every type argument of C or an empty array if the search failed.
+	 */
+	private int[] pi(Type C, Type D) {
+		Type dFromFc = finiteClosure.getType(D.getName());
+		if(dFromFc == null)
+			return new int[0];
+		
+		Set<Type> smallerRhs = finiteClosure.smaller(dFromFc);
+		Optional<Type> opt = smallerRhs.stream().filter(x -> x.getName().equals(C.getName())).findAny();
+		
+		if(!opt.isPresent())
+			return new int[0];
+		
+		Type cFromFc = opt.get();
+		
+		Assert.assertEquals(cFromFc.getTypeArgs().length, dFromFc.getTypeArgs().length);
+		Assert.assertTrue(dFromFc.getTypeArgs().length > 0);
+
+		Type[] cArgs = cFromFc.getTypeArgs();
+		Type[] dArgs = dFromFc.getTypeArgs();
+		
+		int[] permutation = new int[dArgs.length];
+		
+		boolean succ = true;
+		for (int dArgIdx = 0; dArgIdx < dArgs.length && succ; dArgIdx++) {
+			Type dArg = dArgs[dArgIdx];
+			succ = false;
+			for (int pi = 0; pi < cArgs.length; pi++)
+				if (cArgs[pi].getName().equals(dArg.getName())) {
+					permutation[dArgIdx] = pi;
+					succ = true;
+					break;
+				}
+		}
+		
+		if(succ) return permutation;
+		return new int[0];
+	}
+	
 }

src/de/dhbwstuttgart/typinference/unify/model/FiniteClosure.java

@@ -10,11 +10,11 @@ import de.dhbwstuttgart.typinference.unify.model.MPair.PairOperator;
 
 public class FiniteClosure implements IFiniteClosure {
 	
-	private HashMap<Type, Node<Type>> inheritanceGraph;
+	private HashMap<String, Node<Type>> inheritanceGraph;
 	
 	public FiniteClosure(Set<MPair> pairs) {
 		
-		inheritanceGraph = new HashMap<Type, Node<Type>>();
+		inheritanceGraph = new HashMap<String, Node<Type>>();
 		
 		// Build the transitive closure of the inheritance tree
 		for(MPair pair : pairs) {
@@ -23,10 +23,10 @@ public class FiniteClosure implements IFiniteClosure {
 				continue;
 			
 			// Add nodes if not already in the graph
-			if(!inheritanceGraph.containsKey(pair.getLhsType())) 
+			if(!inheritanceGraph.containsKey(pair.getLhsType().getName())) 
-				inheritanceGraph.put(pair.getLhsType(), new Node<Type>(pair.getLhsType()));
+				inheritanceGraph.put(pair.getLhsType().getName(), new Node<Type>(pair.getLhsType()));
-			if(!inheritanceGraph.containsKey(pair.getRhsType())) 
+			if(!inheritanceGraph.containsKey(pair.getRhsType().getName())) 
-				inheritanceGraph.put(pair.getRhsType(), new Node<Type>(pair.getRhsType()));
+				inheritanceGraph.put(pair.getRhsType().getName(), new Node<Type>(pair.getRhsType()));
 			
 			Node<Type> childNode = inheritanceGraph.get(pair.getRhsType());
 			Node<Type> parentNode = inheritanceGraph.get(pair.getLhsType());
@@ -45,10 +45,23 @@ public class FiniteClosure implements IFiniteClosure {
 	 */
 	@Override
 	public Set<Type> smaller(Type type) {
-		if(!inheritanceGraph.containsKey(type))
+		return smaller(type.getName());
+	}
+	
+	@Override
+	public Set<Type> smaller(String typeName) {
+		if(!inheritanceGraph.containsKey(typeName))
 			return new HashSet<>();
 		
-		return inheritanceGraph.get(type).getContentOfDescendants();
+		return inheritanceGraph.get(typeName).getContentOfDescendants();
+	}
+	
+	@Override
+	public Type getType(String typeName) {
+		if(!inheritanceGraph.containsKey(typeName))
+			return null;
+		
+		return inheritanceGraph.get(typeName).getContent();
 	}
 	
 	/**

src/de/dhbwstuttgart/typinference/unify/model/MPair.java

@@ -34,14 +34,6 @@ public class MPair {
 		return type2;
 	}
 	
-	public void setLhsType(Type newLhs) {
-		type1 = newLhs;
-	}
-	
-	public void setRhsType(Type newRhs) {
-		type2 = newRhs;
-	}
-	
 	public PairOperator getPairOp() {
 		return pairOp;
 	}

src/de/dhbwstuttgart/typinference/unify/model/Type.java

@@ -1,12 +1,12 @@
 package de.dhbwstuttgart.typinference.unify.model;
 
-public abstract class Type implements Comparable<Type> {
+public abstract class Type {
 	
-	protected int identifier = 0;
+	protected String typeName = "";
 	protected Type[] typeArgs = null;
 	
-	public int getIdentifier() {
+	public String getName() {
-		return identifier;
+		return typeName;
 	}
 	
 	public Type[] getTypeArgs() {
@@ -22,7 +22,7 @@ public abstract class Type implements Comparable<Type> {
 		
 		Type other = (Type) obj;
 		
-		if(other.getIdentifier() != identifier)
+		if(!other.getName().equals(typeName))
 			return false;
 		
 		Type[] otherTypeArgs = other.getTypeArgs();
@@ -40,18 +40,6 @@ public abstract class Type implements Comparable<Type> {
 
 	@Override
 	public int hashCode() {
-		return 17 + 31 * identifier + 31 * typeArgs.length;
+		return typeName.hashCode();
-	}
-	
-	@Override
-	public int compareTo(Type o) {
-		
-		// Comparison is insensitive to type arguments.
-		
-		if(o.getIdentifier() > identifier)
-			return -1;
-		if(o.getIdentifier() < identifier)
-			return 1;
-		return 0;
 	}
 }