anchor.diff:  }
   
   @parser::members {
  +
  +    private static enum KeyType {
  +      STRING_LITERAL,
  +      IDENT,
  +      STRING_LITERAL_AND_IDENT
  +    }
   
       private static final int DEFAULT_REQUEST_OFFSET = 0;
       private static final int DEFAULT_REQUEST_COUNT = 10;
  
positive.code: @init {
      $json = new JSONObject();
  }
      :   USING RELEVANCE MODEL IDENT prop_list[false] model=relevance_model?
          {
              try {
                  if (model == null) {
  
negative.code:         )* RPAR
      ;
  
  key_value_pair[KeyType keyType] returns [String key, Object val]
  scope {
      KeyType type
  }
  @init {
      $key_value_pair::type = keyType;
  }
      :   ( { $key_value_pair::type == KeyType.STRING_LITERAL ||
              $key_value_pair::type == KeyType.STRING_LITERAL_AND_IDENT}?=> STRING_LITERAL
          | { $key_value_pair::type == KeyType.IDENT ||
              $key_value_pair::type == KeyType.STRING_LITERAL_AND_IDENT}?=> IDENT
          )
          COLON (v=value | vs=python_style_list | vd=python_style_dict)
          {
  