anchor.diff:    return null;
   }
   
  -
   /// Function used to convert a [TextStyle] to a [String] that can be used to key
   /// into results from the Google Fonts api.
   ///
  
positive.code: ///   "700italic": "http://fonts.gstatic.com/s/alegreyasc/v11/taiRGmRtCJ62-O0HhNEa-Z6q4Sk0SK-UEGKDBz4.ttf",
  /// }
  String fontUrlKey(TextStyle textStyle) {
    if (textStyle == null) {
      return 'regular';
    }
    return '${_fontWeightString(textStyle.fontWeight)}'
        '${_fontStyleString(textStyle.fontStyle)}';
  }
  
  String _fontWeightString(FontWeight fontWeight) {
    if (fontWeight == null) {
      return '400';
    }
    return fontWeight.toString().replaceAll('FontWeight.w', '');
  }
  
  String _fontStyleString(FontStyle fontstyle) {
  
negative.code:     return 'italic';
    }
    return '';
  }
  