anchor.diff:  
     static RegExp decimalEntity = new RegExp(r'^#(\d{1,8})$');
     static RegExp hexadecimalEntity = new RegExp(r'^#[xX]([0-9a-fA-F]{1,8})$');
  -  Parser get htmlEntity => ((char('&') >
  +  Parser<String> get htmlEntity1 => (((char('&') >
         ((char('#').maybe + alphanum.many1) ^ (Option a, b) => (a.isDefined ? '#' : '') + b.join()) ) <
         char(';')) ^ (entity) {
       if (htmlEntities.containsKey(entity)) {
  -      return new Str(htmlEntities[entity]);
  +      return htmlEntities[entity];
       }
   
       int code;
  
positive.code:       fenceType = FenceType.TildeFence;
      }
  
      Parser infoStringParser = ((skipSpaces > (noneOf("\n\\ " + fenceChar) | escapedChar1 | char('\\')).many) <
        noneOf("\n" + fenceChar).many) < newline;
      Parser topFenceParser = (char(fenceChar).many + infoStringParser).list;
      ParseResult topFenceRes = topFenceParser.run(s, fenceStartRes.position);
  
negative.code:       if (code > 1114111) {
          code = 0xFFFD;
        }
        return new String.fromCharCode(code);
      }
  
      return '&$entity;';
    }) % "html entity";
    Parser get htmlEntity => htmlEntity1 ^ (str) => new Str(str);
  
    //
    // inline code
  