package lrs.visitor;
import lrs.*;

/**
 * Uses reverse accumulation to remove duplicates from the host list.
 * @author Dung X. Nguyen - Copyright 2005 - All rights reserved.
 */
public class RemDupRev implements IAlgo {
    public final static RemDupRev Singleton = new RemDupRev();
    private RemDupRev() {
    }
    
    /**
     */
    public Object emptyCase(LRStruct host, Object... nu) {
        return host;
    }
    
    /**
     */
    public Object nonEmptyCase(LRStruct host, Object... nu) {
        host.getRest().execute(this);
        if ((Boolean)host.getRest().execute(Contain.Singleton, host.getFirst())) {
            host.removeFront();
        }
        return host;
    }
}