anchor.diff:  							continue;
   						content = (String)bibtexEntry.getField(searchKeys[i].toString());
   				}
  +                noSuchField = false;
   				if (content == null)
   					continue; // paranoia
   				Matcher matcher = valueSpec.matcher(content);
  
positive.code: 			Pattern fieldSpec = ((RegExNode)var_f).getPattern();
  			Pattern valueSpec = ((RegExNode)var_v).getPattern();
  			int pseudoField = 0;
  			// this loop iterates over all regular keys, then over pseudo keys like "type"
  			for (int i = 0; i < searchKeys.length + PSEUDOFIELD_TYPE && !ret; ++i) {
  				String content;
  
negative.code: 					break;
  				}
  			}
              if (noSuchField && matchType == MATCH_DOES_NOT_CONTAIN)
                  ret = true; // special case
  		}
  	)
  	;
  