anchor.diff:  			Pattern fieldSpec = ((RegExNode)var_f).getPattern();
   			Pattern valueSpec = ((RegExNode)var_v).getPattern();
   			int pseudoField = 0;
  +            boolean noSuchField = true;
   			// 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;
  
positive.code: 					break;
  				}
  			}
  		}
  	)
  	;
  
negative.code: 							continue;
  						content = (String)bibtexEntry.getField(searchKeys[i].toString());
  				}
                  noSuchField = false;
  				if (content == null)
  					continue; // paranoia
  				Matcher matcher = valueSpec.matcher(content);
  