/**
 * Refinement mapping sort BinaryTree[Element] into a class LinkedBinaryTree
 *
 * Project <A HREF = "http://gloss.di.fc.ul.pt/quest/"> Quest</A>.
 *
 * @author Vasco T. Vasconcelos
 * @version $Id: LinkedBinaryTree.rfn 349 2008-04-16 22:38:19Z vv $
 */

refinement<E>
	
    Element is E

    BinaryTree[Element] is LinkedBinaryTree<E> {
    
        make: e:Element l:BinaryTree[Element] r:BinaryTree[Element] --> BinaryTree[Element]	       
              is LinkedBinaryTree(E e, LinkedBinaryTree<E> l, LinkedBinaryTree<E> r);  
        empty: --> BinaryTree[Element]         
              is LinkedBinaryTree();									
        data: BinaryTree[Element] -->? Element 
              is E data();
        leftSubtree: BinaryTree[Element] -->? return:BinaryTree[Element] 
              is LinkedBinaryTree<E> leftSubtree();                                  
        rightSubtree: BinaryTree[Element] -->? return:BinaryTree[Element]
              is LinkedBinaryTree<E> rightSubtree();                                            
        isEmpty: BinaryTree[Element] 		   
              is boolean isEmpty();
		isLeaf: BinaryTree[Element]
              is boolean isLeaf();
		height: BinaryTree[Element] --> int    
		      is int height();
		occurrences: BinaryTree[Element] e:Element --> int        
		      is int occurrences(E e);                  
		isBalanced: BinaryTree[Element] 	   
		      is boolean isBalanced();
		isPerfect:  BinaryTree[Element] 	  
		      is boolean isPerfect();
		isComplete: BinaryTree[Element]		   
		      is boolean isComplete();
    }
end refinement