anchor.diff:      RegExp single_underscore = new RegExp(r"(?! )_(?! )([^_]+)(?! )\_(?! )");
       RegExp double_asterix = new RegExp(r"(?! )\*{2}(?! )([^*]+)(?! )\*{2}(?! )");
       RegExp double_underscore = new RegExp(r"(?! )_{2}(?! )([^_]+)(?! )_{2}(?! )");
  +    RegExp single_tick_code = new RegExp(r"(?! )`(?! )([^`]+)(?! )`(?! )");
  +    
       RegExp spaced_asterix = new RegExp(r" (\*) ");
       RegExp spaced_underscore = new RegExp(r" (_) ");
       RegExp backslash_asterix = new RegExp(r"\\(\*)");
  
positive.code:             ret = "${ret}${cur.generate_html()}";
          }
          ret = "${ret}</blockquote>";
          return ret;
      }
  }
  
negative.code: }
  
  main_wrapped() {
      String inp = "A First Level Header\n====================\n\nA Second Level Header\n---------------------\n\nNow is the time for all good men to come to\nthe aid of their `country`. This is just a\nre_gu_lar paragraph.\n\nThe quick brown fox jumped over the lazy\ndog's back.\n\n### Header 3\n\n> This is a blockquote.\n> \n> This is the second paragraph in the blockquote.\n>\n> ## This is an H2 in a blockquote";
      RegExp single_asterix = new RegExp(r"(?! )\*(?! )[^*]+(?! )\*(?! )");
      print(markdown_to_html(inp));
  }
  