anchor.diff:      return [value, value + PAIR_RESOLUTIONS[i - 1]];
     }
   
  -/**
  -    Decode the grid refinement portion of an OLC code.
  -    This decodes an OLC code using the grid refinement method.
  -    Args:
  -    code: A valid OLC code sequence that is only the grid refinement
  -    portion. This is the portion of a code starting at position 11.
  - */
  +  /// Decode the grid refinement portion of an OLC code.
  +  ///
  +  /// This decodes an OLC code using the grid refinement method.
  +  ///
  +  /// Args:
  +  ///
  +  /// * [code]: A valid OLC code sequence that is only the grid refinement
  +  /// portion. This is the portion of a code starting at position 11.
     CodeArea decodeGrid(String code) {
       var latitudeLo = 0.0;
       var longitudeLo = 0.0;
  
positive.code:         longitude[1] - LONGITUDE_MAX, code.length);
    }
  
  /**
      Decode either a latitude or longitude sequence.
      This decodes the latitude or longitude sequence of a lat/lng pair encoding.
      Starting at the character at position offset, every second character is
      decoded and the value returned.
      Args:
      code: A valid OLC code, presumed to be full, with the separator removed.
      offset: The character to start from.
      Returns:
      A pair of the low and high values. The low value comes from decoding the
      characters. The high value is the low value plus the resolution of the
      last position. Both values are offset into positive ranges and will need
      to be corrected before use.
   */
    List<double> decodePairsSequence(String code, double offset) {
      int i = 0;
      num value = 0;
  
negative.code:     return code;
    }
  
    /// Encode a location using the grid refinement method into an OLC string.
    ///
    /// The grid refinement method divides the area into a grid of 4x5, and uses a
    /// single character to refine the area. This allows default accuracy OLC
    /// codes to be refined with just a single character.
    ///
    /// Args:
    ///
    /// * [latitude]: A latitude in signed decimal degrees.
    /// * [longitude]: A longitude in signed decimal degrees.
    /// * [codeLength]: The number of characters required.
    String encodeGrid(double latitude, double longitude, int codeLength) {
      var code = '';
      var latPlaceValue = GRID_SIZE_DEGREES;
  