anchor.diff:      return false;
     }
   
  -  int separatorIndex = code.indexOf(SEPARATOR);
  +  int separatorIndex = code.indexOf(separator);
     // There must be a single separator at an even index and position should be < SEPARATOR_POSITION.
     if (separatorIndex == -1 ||
  -      separatorIndex != code.lastIndexOf(SEPARATOR) ||
  -      separatorIndex > SEPARATOR_POSITION ||
  +      separatorIndex != code.lastIndexOf(separator) ||
  +      separatorIndex > separatorPosition ||
         separatorIndex % 2 == 1) {
       return false;
     }
   
     // We can have an even number of padding characters before the separator,
     // but then it must be the final character.
  -  if (code.indexOf(PADDING) > -1) {
  +  if (code.indexOf(padding) > -1) {
       // Not allowed to start with them!
  -    if (code.indexOf(PADDING) == 0) {
  +    if (code.indexOf(padding) == 0) {
         return false;
       }
       // There can only be one group and it must have even length.
  -    var padMatch = new RegExp('($PADDING+)').allMatches(code).toList();
  +    var padMatch = new RegExp('($padding+)').allMatches(code).toList();
       if (padMatch.length != 1) {
         return false;
       }
       var match = padMatch[0].group(0);
  -    if (match.length % 2 == 1 || match.length > SEPARATOR_POSITION - 2) {
  +    if (match.length % 2 == 1 || match.length > separatorPosition - 2) {
         return false;
       }
       // If the code is long enough to end with a separator, make sure it does.
  -    if (code[code.length - 1] != SEPARATOR) {
  +    if (code[code.length - 1] != separator) {
         return false;
       }
     }
  
positive.code: CodeArea decodeGrid(String code) {
    var latitudeLo = 0.0;
    var longitudeLo = 0.0;
    var latPlaceValue = GRID_SIZE_DEGREES;
    var lngPlaceValue = GRID_SIZE_DEGREES;
    var i = 0;
    while (i < code.length) {
      var codeIndex = _decode[code.codeUnitAt(i)];
      var row = (codeIndex / GRID_COLUMNS).floor();
      var col = codeIndex % GRID_COLUMNS;
  
      latPlaceValue /= GRID_ROWS;
      lngPlaceValue /= GRID_COLUMNS;
  
      latitudeLo += row * latPlaceValue;
      longitudeLo += col * lngPlaceValue;
  
negative.code:   // Clean up the passed code.
    shortCode = shortCode.toUpperCase();
    // Compute the number of digits we need to recover.
    var paddingLength = separatorPosition - shortCode.indexOf(separator);
    // The resolution (height and width) of the padded area in degrees.
    var resolution = pow(20, 2 - (paddingLength / 2));
    // Distance from the center to an edge (in degrees).
  