commenting and rule application

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

@@ -1,6 +1,11 @@
 package de.dhbwstuttgart.typeinference.unifynew;
 
+import java.util.AbstractQueue;
+import java.util.ArrayList;
 import java.util.HashSet;
+import java.util.LinkedHashSet;
+import java.util.LinkedList;
+import java.util.Queue;
 import java.util.Set;
 
 import de.dhbwstuttgart.typeinference.Menge;
@@ -56,13 +61,58 @@ public class Unify {
 		throw new NotImplementedException();
 	}
 	
-	private Set<MPair> applyTypeUnificationRules(Set<MPair> eq, IFiniteClosure fc) {
+	private LinkedHashSet<MPair> applyTypeUnificationRules(Set<MPair> eq, IFiniteClosure fc) {
 		
-		boolean changedInLastIteration = true;
+		/*
+		 * Strategy for better performance
+		 * 
+		 * 1. 	Erase all erasable rules
+		 * 2. 	Apply all possible rules to a single pair, then move it to the result set.
+		 *    	Iterating over pairs first, then iterating over rules prevents the algorithm
+		 *    	from trying to apply rules to a "finished" pair over and over.
+		 * 2.1 	Apply all rules repeatedly except for erase rules. If
+		 * 		the application of a rule creates new pairs, check immediately
+		 * 		against the erase rules.
+		 * 2.2	Always use the ordering (IComparable) of the mapped types as the permutation.
+		 * 		This is saving the time to generate and test permutations.
+		 */
 		
-		HashSet<MPair>
 		
+		LinkedHashSet<MPair> targetSet = new LinkedHashSet<MPair>();
+		
+		ArrayList<MPair> eqQueue = new ArrayList<>();
+		
+		/*
+		 * Erase all erasable pairs or add them to the queue for further processing
+		 */
+		for(MPair pair : eq)
+			if(!(erase1(pair) || erase2(pair) || erase3(pair))) 
+				eqQueue.add(pair);
+		
+		while(!eq.isEmpty()) {
+			boolean ruleWasApplied = true;
+			
+			MPair pair = eqQueue.get(0);
+			
+			while(ruleWasApplied) {
+				ruleWasApplied = false;
+				
+				
+			}
+		}
 		
 		throw new NotImplementedException();
 	}
+	
+	private boolean erase1(MPair pair) {
+		return true;
+	}
+	
+	private boolean erase2(MPair pair) {
+		return true;
+	}
+	
+	private boolean erase3(MPair pair) {
+		return true;
+	}
 }