anchor.diff:     * Format the part after the decimal place in a fixed point number.
      */
     void _formatFractionPart(String fractionPart) {
  -    var fractionCodes = fractionPart.charCodes;
  +    var fractionCodes = fractionPart.codeUnits;
       var fractionLength = fractionPart.length;
       while (fractionPart[fractionLength - 1] == '0' &&
              fractionLength > _minimumFractionDigits + 1) {
  
positive.code:     for (var i = 0; i < numberOfDigits - basic.length; i++) {
        _add(symbols.ZERO_DIGIT);
      }
      for (var x in basic.charCodes) {
        _addDigit(x);
      }
    }
  
negative.code:       paddingDigits.add(symbols.ZERO_DIGIT);
        intValue = intValue ~/ 10;
      }
      var integerDigits = "${intValue}${paddingDigits}".codeUnits;
      var digitLength = integerDigits.length;
  
      if (_hasPrintableIntegerPart(intValue)) {
  