anchor.diff:    }
   }
   
  -abstract class SyntaxHighlighter {
  +abstract class SyntaxHighlighter { // ignore: one_member_abstracts
     TextSpan format(String source);
   }
   
   class _DefaultSyntaxHighlighter extends SyntaxHighlighter{
     _DefaultSyntaxHighlighter(this.style);
  +
     final TextStyle style;
   
     TextSpan format(String source) {
  
positive.code:         children.add(_stackToTextSpan(list[i]));
        }
  
        String text = null;
        if (children.length == 1 && _isPlainText(children[0])) {
          text = children[0].text;
          children = null;
  
negative.code:       _Block newBlock = new _Block(element.tag, element.attributes, _markdownStyle, new List<String>.from(_listIndents), blockList.length);
        blockList.add(newBlock);
      } else {
        _LinkInfo linkInfo;
        if (element.tag == 'a') {
          linkInfo = _linkHandler.createLinkInfo(element.attributes['href']);
        }
  