anchor.diff:  <%@ page import="org.apache.log4j.*" %>
   <%@ page import="com.ecyrd.jspwiki.*" %>
   <%@ page import="com.ecyrd.jspwiki.tags.WikiTagBase" %>
  +<%@ page import="com.ecyrd.jspwiki.tags.InsertDiffTag" %>
   <%@ taglib uri="/WEB-INF/jspwiki.tld" prefix="wiki" %>
   
   <%! 
  
positive.code:     // If "r1" is null, then assume current version (= -1)
      // If "r2" is null, then assume the previous version (=current version-1)
  
      String srev1 = request.getParameter("r1");
      String srev2 = request.getParameter("r2");
  
  
negative.code:     pageContext.setAttribute( WikiTagBase.ATTR_CONTEXT,
                                wikiContext );
  
      pageContext.setAttribute( InsertDiffTag.ATTR_OLDVERSION,
                                new Integer(ver1) );
      pageContext.setAttribute( InsertDiffTag.ATTR_NEWVERSION,
                                new Integer(ver2) );
  
      String versionDescription1 = getVersionText( ver1 );
      String versionDescription2 = getVersionText( ver2 );
  
  