text: "use strict";
  var Markdown;
  
  if (typeof exports === "object" && typeof require === "function") // we're in a CommonJS (e.g. Node.js) module
      Markdown = exports;
  else
      Markdown = {};
  
  // The following text is included for historical reasons, but should
  // be taken with a pinch of salt; it's not all true anymore.
  
  //
  // Wherever possible, Showdown is a straight, line-by-line port
  // of the Perl version of Markdown.
  //
  // This is not a normal parser design; it's basically just a
  // series of string substitutions.  It's hard to read and
  // maintain this way,  but keeping Showdown close to the original
  // design makes it easier to port new features.
  //
  // More importantly, Showdown behaves like markdown.pl in most
  // edge cases.  So web applications can do client-side preview
  // in Javascript, and then build identical HTML on the server.
  //
  // This port needs the new RegExp functionality of ECMA 262,
  // 3rd Edition (i.e. Javascript 1.5).  Most modern web browsers
  // should do fine.  Even with the new regular expression features,
  // We do a lot of work to emulate Perl's regex functionality.
  // The tricky changes in this file mostly have the "attacklab:"
  // label.  Major or self-explanatory changes don't.
  //
  // Smart diff tools like Araxis Merge will be able to match up
  // this file with markdown.pl in a useful way.  A little tweaking
  // helps: in a copy of markdown.pl, replace "#" with "//" and
  // replace "$text" with "text".  Be sure to ignore whitespace
  // and line endings.
  //
  
  
  //
  // Usage:
  //
  //   var text = "Markdown *rocks*.";
  //
  //   var converter = new Markdown.Converter();
  //   var html = converter.makeHtml(text);
  //
  //   alert(html);
  //
  // Note: move the sample code to the bottom of this
  // file before uncommenting it.
  //
  
  (function () {
  
      function identity(x) { return x; }
      function returnFalse(x) { return false; }
  
      function HookCollection() { }
  
      HookCollection.prototype = {
  
          chain: function (hookname, func) {
              var original = this[hookname];
              if (!original)
                  throw new Error("unknown hook " + hookname);
  
              if (original === identity)
                  this[hookname] = func;
              else
                  this[hookname] = function (text) {
                      var args = Array.prototype.slice.call(arguments, 0);
                      args[0] = original.apply(null, args);
                      return func.apply(null, args);
                  };
          },
          set: function (hookname, func) {
              if (!this[hookname])
                  throw new Error("unknown hook " + hookname);
              this[hookname] = func;
          },
          addNoop: function (hookname) {
              this[hookname] = identity;
          },
          addFalse: function (hookname) {
              this[hookname] = returnFalse;
          }
      };
  
      Markdown.HookCollection = HookCollection;
  
      // g_urls and g_titles allow arbitrary user-entered strings as keys. This
      // caused an exception (and hence stopped the rendering) when the user entered
      // e.g. [push] or [__proto__]. Adding a prefix to the actual key prevents this
      // (since no builtin property starts with "s_"). See
      // http://meta.stackexchange.com/questions/64655/strange-wmd-bug
      // (granted, switching from Array() to Object() alone would have left only __proto__
      // to be a problem)
      function SaveHash() { }
      SaveHash.prototype = {
          set: function (key, value) {
              this["s_" + key] = value;
          },
          get: function (key) {
              return this["s_" + key];
          }
      };
  
      Markdown.Converter = function (OPTIONS) {
          var pluginHooks = this.hooks = new HookCollection();
          
          // given a URL that was encountered by itself (without markup), should return the link text that's to be given to this link
          pluginHooks.addNoop("plainLinkText");
          
          // called with the orignal text as given to makeHtml. The result of this plugin hook is the actual markdown source that will be cooked
          pluginHooks.addNoop("preConversion");
          
          // called with the text once all normalizations have been completed (tabs to spaces, line endings, etc.), but before any conversions have
          pluginHooks.addNoop("postNormalization");
          
          // Called with the text before / after creating block elements like code blocks and lists. Note that this is called recursively
          // with inner content, e.g. it's called with the full text, and then only with the content of a blockquote. The inner
          // call will receive outdented text.
          pluginHooks.addNoop("preBlockGamut");
          pluginHooks.addNoop("postBlockGamut");
          
          // called with the text of a single block element before / after the span-level conversions (bold, code spans, etc.) have been made
          pluginHooks.addNoop("preSpanGamut");
          pluginHooks.addNoop("postSpanGamut");
          
          // called with the final cooked HTML code. The result of this plugin hook is the actual output of makeHtml
          pluginHooks.addNoop("postConversion");
  
          //
          // Private state of the converter instance:
          //
  
          // Global hashes, used by various utility routines
          var g_urls;
          var g_titles;
          var g_html_blocks;
  
          // Used to track when we're inside an ordered or unordered list
          // (see _ProcessListItems() for details):
          var g_list_level;
          
          OPTIONS = OPTIONS || {};
          var asciify = identity, deasciify = identity;
          if (OPTIONS.nonAsciiLetters) {
  
              /* In JavaScript regular expressions, \w only denotes [a-zA-Z0-9_].
               * That's why there's inconsistent handling e.g. with intra-word bolding
               * of Japanese words. That's why we do the following if OPTIONS.nonAsciiLetters
               * is true:
               *
               * Before doing bold and italics, we find every instance
               * of a unicode word character in the Markdown source that is not
               * matched by \w, and the letter "Q". We take the character's code point
               * and encode it in base 51, using the "digits"
               *
               *     A, B, ..., P, R, ..., Y, Z, a, b, ..., y, z
               *
               * delimiting it with "Q" on both sides. For example, the source
               *
               * > In Chinese, the smurfs are called 藍精靈, meaning "blue spirits".
               *
               * turns into
               *
               * > In Chinese, the smurfs are called QNIhQQMOIQQOuUQ, meaning "blue spirits".
               *
               * Since everything that is a letter in Unicode is now a letter (or
               * several letters) in ASCII, \w and \b should always do the right thing.
               *
               * After the bold/italic conversion, we decode again; since "Q" was encoded
               * alongside all non-ascii characters (as "QBfQ"), and the conversion
               * will not generate "Q", the only instances of that letter should be our
               * encoded characters. And since the conversion will not break words, the
               * "Q...Q" should all still be in one piece.
               *
               * We're using "Q" as the delimiter because it's probably one of the
               * rarest characters, and also because I can't think of any special behavior
               * that would ever be triggered by this letter (to use a silly example, if we
               * delimited with "H" on the left and "P" on the right, then "Ψ" would be
               * encoded as "HTTP", which may cause special behavior). The latter would not
               * actually be a huge issue for bold/italic, but may be if we later use it
               * in other places as well.
               * */            
              (function () {
                  var lettersThatJavaScriptDoesNotKnowAndQ = /[Q\u00aa\u00b5\u00ba\u00c0-\u00d6\u00d8-\u00f6\u00f8-\u02c1\u02c6-\u02d1\u02e0-\u02e4\u02ec\u02ee\u0370-\u0374\u0376-\u0377\u037a-\u037d\u0386\u0388-\u038a\u038c\u038e-\u03a1\u03a3-\u03f5\u03f7-\u0481\u048a-\u0523\u0531-\u0556\u0559\u0561-\u0587\u05d0-\u05ea\u05f0-\u05f2\u0621-\u064a\u0660-\u0669\u066e-\u066f\u0671-\u06d3\u06d5\u06e5-\u06e6\u06ee-\u06fc\u06ff\u0710\u0712-\u072f\u074d-\u07a5\u07b1\u07c0-\u07ea\u07f4-\u07f5\u07fa\u0904-\u0939\u093d\u0950\u0958-\u0961\u0966-\u096f\u0971-\u0972\u097b-\u097f\u0985-\u098c\u098f-\u0990\u0993-\u09a8\u09aa-\u09b0\u09b2\u09b6-\u09b9\u09bd\u09ce\u09dc-\u09dd\u09df-\u09e1\u09e6-\u09f1\u0a05-\u0a0a\u0a0f-\u0a10\u0a13-\u0a28\u0a2a-\u0a30\u0a32-\u0a33\u0a35-\u0a36\u0a38-\u0a39\u0a59-\u0a5c\u0a5e\u0a66-\u0a6f\u0a72-\u0a74\u0a85-\u0a8d\u0a8f-\u0a91\u0a93-\u0aa8\u0aaa-\u0ab0\u0ab2-\u0ab3\u0ab5-\u0ab9\u0abd\u0ad0\u0ae0-\u0ae1\u0ae6-\u0aef\u0b05-\u0b0c\u0b0f-\u0b10\u0b13-\u0b28\u0b2a-\u0b30\u0b32-\u0b33\u0b35-\u0b39\u0b3d\u0b5c-\u0b5d\u0b5f-\u0b61\u0b66-\u0b6f\u0b71\u0b83\u0b85-\u0b8a\u0b8e-\u0b90\u0b92-\u0b95\u0b99-\u0b9a\u0b9c\u0b9e-\u0b9f\u0ba3-\u0ba4\u0ba8-\u0baa\u0bae-\u0bb9\u0bd0\u0be6-\u0bef\u0c05-\u0c0c\u0c0e-\u0c10\u0c12-\u0c28\u0c2a-\u0c33\u0c35-\u0c39\u0c3d\u0c58-\u0c59\u0c60-\u0c61\u0c66-\u0c6f\u0c85-\u0c8c\u0c8e-\u0c90\u0c92-\u0ca8\u0caa-\u0cb3\u0cb5-\u0cb9\u0cbd\u0cde\u0ce0-\u0ce1\u0ce6-\u0cef\u0d05-\u0d0c\u0d0e-\u0d10\u0d12-\u0d28\u0d2a-\u0d39\u0d3d\u0d60-\u0d61\u0d66-\u0d6f\u0d7a-\u0d7f\u0d85-\u0d96\u0d9a-\u0db1\u0db3-\u0dbb\u0dbd\u0dc0-\u0dc6\u0e01-\u0e30\u0e32-\u0e33\u0e40-\u0e46\u0e50-\u0e59\u0e81-\u0e82\u0e84\u0e87-\u0e88\u0e8a\u0e8d\u0e94-\u0e97\u0e99-\u0e9f\u0ea1-\u0ea3\u0ea5\u0ea7\u0eaa-\u0eab\u0ead-\u0eb0\u0eb2-\u0eb3\u0ebd\u0ec0-\u0ec4\u0ec6\u0ed0-\u0ed9\u0edc-\u0edd\u0f00\u0f20-\u0f29\u0f40-\u0f47\u0f49-\u0f6c\u0f88-\u0f8b\u1000-\u102a\u103f-\u1049\u1050-\u1055\u105a-\u105d\u1061\u1065-\u1066\u106e-\u1070\u1075-\u1081\u108e\u1090-\u1099\u10a0-\u10c5\u10d0-\u10fa\u10fc\u1100-\u1159\u115f-\u11a2\u11a8-\u11f9\u1200-\u1248\u124a-\u124d\u1250-\u1256\u1258\u125a-\u125d\u1260-\u1288\u128a-\u128d\u1290-\u12b0\u12b2-\u12b5\u12b8-\u12be\u12c0\u12c2-\u12c5\u12c8-\u12d6\u12d8-\u1310\u1312-\u1315\u1318-\u135a\u1380-\u138f\u13a0-\u13f4\u1401-\u166c\u166f-\u1676\u1681-\u169a\u16a0-\u16ea\u1700-\u170c\u170e-\u1711\u1720-\u1731\u1740-\u1751\u1760-\u176c\u176e-\u1770\u1780-\u17b3\u17d7\u17dc\u17e0-\u17e9\u1810-\u1819\u1820-\u1877\u1880-\u18a8\u18aa\u1900-\u191c\u1946-\u196d\u1970-\u1974\u1980-\u19a9\u19c1-\u19c7\u19d0-\u19d9\u1a00-\u1a16\u1b05-\u1b33\u1b45-\u1b4b\u1b50-\u1b59\u1b83-\u1ba0\u1bae-\u1bb9\u1c00-\u1c23\u1c40-\u1c49\u1c4d-\u1c7d\u1d00-\u1dbf\u1e00-\u1f15\u1f18-\u1f1d\u1f20-\u1f45\u1f48-\u1f4d\u1f50-\u1f57\u1f59\u1f5b\u1f5d\u1f5f-\u1f7d\u1f80-\u1fb4\u1fb6-\u1fbc\u1fbe\u1fc2-\u1fc4\u1fc6-\u1fcc\u1fd0-\u1fd3\u1fd6-\u1fdb\u1fe0-\u1fec\u1ff2-\u1ff4\u1ff6-\u1ffc\u203f-\u2040\u2054\u2071\u207f\u2090-\u2094\u2102\u2107\u210a-\u2113\u2115\u2119-\u211d\u2124\u2126\u2128\u212a-\u212d\u212f-\u2139\u213c-\u213f\u2145-\u2149\u214e\u2183-\u2184\u2c00-\u2c2e\u2c30-\u2c5e\u2c60-\u2c6f\u2c71-\u2c7d\u2c80-\u2ce4\u2d00-\u2d25\u2d30-\u2d65\u2d6f\u2d80-\u2d96\u2da0-\u2da6\u2da8-\u2dae\u2db0-\u2db6\u2db8-\u2dbe\u2dc0-\u2dc6\u2dc8-\u2dce\u2dd0-\u2dd6\u2dd8-\u2dde\u2e2f\u3005-\u3006\u3031-\u3035\u303b-\u303c\u3041-\u3096\u309d-\u309f\u30a1-\u30fa\u30fc-\u30ff\u3105-\u312d\u3131-\u318e\u31a0-\u31b7\u31f0-\u31ff\u3400-\u4db5\u4e00-\u9fc3\ua000-\ua48c\ua500-\ua60c\ua610-\ua62b\ua640-\ua65f\ua662-\ua66e\ua67f-\ua697\ua717-\ua71f\ua722-\ua788\ua78b-\ua78c\ua7fb-\ua801\ua803-\ua805\ua807-\ua80a\ua80c-\ua822\ua840-\ua873\ua882-\ua8b3\ua8d0-\ua8d9\ua900-\ua925\ua930-\ua946\uaa00-\uaa28\uaa40-\uaa42\uaa44-\uaa4b\uaa50-\uaa59\uac00-\ud7a3\uf900-\ufa2d\ufa30-\ufa6a\ufa70-\ufad9\ufb00-\ufb06\ufb13-\ufb17\ufb1d\ufb1f-\ufb28\ufb2a-\ufb36\ufb38-\ufb3c\ufb3e\ufb40-\ufb41\ufb43-\ufb44\ufb46-\ufbb1\ufbd3-\ufd3d\ufd50-\ufd8f\ufd92-\ufdc7\ufdf0-\ufdfb\ufe33-\ufe34\ufe4d-\ufe4f\ufe70-\ufe74\ufe76-\ufefc\uff10-\uff19\uff21-\uff3a\uff3f\uff41-\uff5a\uff66-\uffbe\uffc2-\uffc7\uffca-\uffcf\uffd2-\uffd7\uffda-\uffdc]/g;
                  var cp_Q = "Q".charCodeAt(0);
                  var cp_A = "A".charCodeAt(0);
                  var cp_Z = "Z".charCodeAt(0);
                  var dist_Za = "a".charCodeAt(0) - cp_Z - 1;
                  
                  asciify = function(text) {
                      return text.replace(lettersThatJavaScriptDoesNotKnowAndQ, function (m) {
                          var c = m.charCodeAt(0);
                          var s = "";
                          var v;
                          while (c > 0) {
                              v = (c % 51) + cp_A;
                              if (v >= cp_Q)
                                  v++;
                              if (v > cp_Z)
                                  v += dist_Za;
                              s = String.fromCharCode(v) + s;
                              c = c / 51 | 0;
                          }
                          return "Q" + s + "Q";
                      })
                  };
                  
                  deasciify = function(text) {
                      return text.replace(/Q([A-PR-Za-z]{1,3})Q/g, function (m, s) {
                          var c = 0;
                          var v;
                          for (var i = 0; i < s.length; i++) {
                              v = s.charCodeAt(i);
                              if (v > cp_Z)
                                  v -= dist_Za;
                              if (v > cp_Q)
                                  v--;
                              v -= cp_A;
                              c = (c * 51) + v;
                          }
                          return String.fromCharCode(c);
                      })
                  }                
              })();
          }
          
          var _DoItalicsAndBold = OPTIONS.asteriskIntraWordEmphasis ? _DoItalicsAndBold_AllowIntrawordWithAsterisk : _DoItalicsAndBoldStrict;
  
          this.makeHtml = function (text) {
  
              //
              // Main function. The order in which other subs are called here is
              // essential. Link and image substitutions need to happen before
              // _EscapeSpecialCharsWithinTagAttributes(), so that any *'s or _'s in the <a>
              // and <img> tags get encoded.
              //
  
              // This will only happen if makeHtml on the same converter instance is called from a plugin hook.
              // Don't do that.
              if (g_urls)
                  throw new Error("Recursive call to converter.makeHtml");
          
              // Create the private state objects.
              g_urls = new SaveHash();
              g_titles = new SaveHash();
              g_html_blocks = [];
              g_list_level = 0;
  
              text = pluginHooks.preConversion(text);
  
              // attacklab: Replace ~ with ~T
              // This lets us use tilde as an escape char to avoid md5 hashes
              // The choice of character is arbitray; anything that isn't
              // magic in Markdown will work.
              text = text.replace(/~/g, "~T");
  
              // attacklab: Replace $ with ~D
              // RegExp interprets $ as a special character
              // when it's in a replacement string
              text = text.replace(/\$/g, "~D");
  
              // Standardize line endings
              text = text.replace(/\r\n/g, "\n"); // DOS to Unix
              text = text.replace(/\r/g, "\n"); // Mac to Unix
  
              // Make sure text begins and ends with a couple of newlines:
              text = "\n\n" + text + "\n\n";
  
              // Convert all tabs to spaces.
              text = _Detab(text);
  
              // Strip any lines consisting only of spaces and tabs.
              // This makes subsequent regexen easier to write, because we can
              // match consecutive blank lines with /\n+/ instead of something
              // contorted like /[ \t]*\n+/ .
              text = text.replace(/^[ \t]+$/mg, "");
              
              text = pluginHooks.postNormalization(text);
  
              // Turn block-level HTML blocks into hash entries
              text = _HashHTMLBlocks(text);
  
              // Strip link definitions, store in hashes.
              text = _StripLinkDefinitions(text);
  
              text = _RunBlockGamut(text);
  
              text = _UnescapeSpecialChars(text);
  
              // attacklab: Restore dollar signs
              text = text.replace(/~D/g, "$$");
  
              // attacklab: Restore tildes
              text = text.replace(/~T/g, "~");
  
              text = pluginHooks.postConversion(text);
  
              g_html_blocks = g_titles = g_urls = null;
  
              return text;
          };
  
          function _StripLinkDefinitions(text) {
              //
              // Strips link definitions from text, stores the URLs and titles in
              // hash references.
              //
  
              // Link defs are in the form: ^[id]: url "optional title"
  
              /*
              text = text.replace(/
                  ^[ ]{0,3}\[([^\[\]]+)\]:  // id = $1  attacklab: g_tab_width - 1
                  [ \t]*
                  \n?                 // maybe *one* newline
                  [ \t]*
                  <?(\S+?)>?          // url = $2
                  (?=\s|$)            // lookahead for whitespace instead of the lookbehind removed below
                  [ \t]*
                  \n?                 // maybe one newline
                  [ \t]*
                  (                   // (potential) title = $3
                      (\n*)           // any lines skipped = $4 attacklab: lookbehind removed
                      [ \t]+
                      ["(]
                      (.+?)           // title = $5
                      [")]
                      [ \t]*
                  )?                  // title is optional
                  (\n+)             // subsequent newlines = $6, capturing because they must be put back if the potential title isn't an actual title
              /gm, function(){...});
              */
  
              text = text.replace(/^[ ]{0,3}\[([^\[\]]+)\]:[ \t]*\n?[ \t]*<?(\S+?)>?(?=\s|$)[ \t]*\n?[ \t]*((\n*)["(](.+?)[")][ \t]*)?(\n+)/gm,
                  function (wholeMatch, m1, m2, m3, m4, m5, m6) {
                      m1 = m1.toLowerCase();
                      g_urls.set(m1, _EncodeAmpsAndAngles(m2));  // Link IDs are case-insensitive
                      if (m4) {
                          // Oops, found blank lines, so it's not a title.
                          // Put back the parenthetical statement we stole.
                          return m3 + m6;
                      } else if (m5) {
                          g_titles.set(m1, m5.replace(/"/g, "&quot;"));
                      }
  
                      // Completely remove the definition from the text
                      return "";
                  }
              );
  
              return text;
          }
  
          function _HashHTMLBlocks(text) {
  
              // Hashify HTML blocks:
              // We only want to do this for block-level HTML tags, such as headers,
              // lists, and tables. That's because we still want to wrap <p>s around
              // "paragraphs" that are wrapped in non-block-level tags, such as anchors,
              // phrase emphasis, and spans. The list of tags we're looking for is
              // hard-coded:
              var block_tags_a = "p|div|h[1-6]|blockquote|pre|table|dl|ol|ul|script|noscript|form|fieldset|iframe|math|ins|del"
              var block_tags_b = "p|div|h[1-6]|blockquote|pre|table|dl|ol|ul|script|noscript|form|fieldset|iframe|math"
  
              // First, look for nested blocks, e.g.:
              //   <div>
              //     <div>
              //     tags for inner block must be indented.
              //     </div>
              //   </div>
              //
              // The outermost tags must start at the left margin for this to match, and
              // the inner nested divs must be indented.
              // We need to do this before the next, more liberal match, because the next
              // match will start at the first `<div>` and stop at the first `</div>`.
  
              // attacklab: This regex can be expensive when it fails.
  
              /*
              text = text.replace(/
                  (                       // save in $1
                      ^                   // start of line  (with /m)
                      <($block_tags_a)    // start tag = $2
                      \b                  // word break
                                          // attacklab: hack around khtml/pcre bug...
                      [^\r]*?\n           // any number of lines, minimally matching
                      </\2>               // the matching end tag
                      [ \t]*              // trailing spaces/tabs
                      (?=\n+)             // followed by a newline
                  )                       // attacklab: there are sentinel newlines at end of document
              /gm,function(){...}};
              */
              text = text.replace(/^(<(p|div|h[1-6]|blockquote|pre|table|dl|ol|ul|script|noscript|form|fieldset|iframe|math|ins|del)\b[^\r]*?\n<\/\2>[ \t]*(?=\n+))/gm, hashMatch);
  
              //
              // Now match more liberally, simply from `\n<tag>` to `</tag>\n`
              //
  
              /*
              text = text.replace(/
                  (                       // save in $1
                      ^                   // start of line  (with /m)
                      <($block_tags_b)    // start tag = $2
                      \b                  // word break
                                          // attacklab: hack around khtml/pcre bug...
                      [^\r]*?             // any number of lines, minimally matching
                      .*</\2>             // the matching end tag
                      [ \t]*              // trailing spaces/tabs
                      (?=\n+)             // followed by a newline
                  )                       // attacklab: there are sentinel newlines at end of document
              /gm,function(){...}};
              */
              text = text.replace(/^(<(p|div|h[1-6]|blockquote|pre|table|dl|ol|ul|script|noscript|form|fieldset|iframe|math)\b[^\r]*?.*<\/\2>[ \t]*(?=\n+)\n)/gm, hashMatch);
  
              // Special case just for <hr />. It was easier to make a special case than
              // to make the other regex more complicated.  
  
              /*
              text = text.replace(/
                  \n                  // Starting after a blank line
                  [ ]{0,3}
                  (                   // save in $1
                      (<(hr)          // start tag = $2
                          \b          // word break
                          ([^<>])*?
                      \/?>)           // the matching end tag
                      [ \t]*
                      (?=\n{2,})      // followed by a blank line
                  )
              /g,hashMatch);
              */
              text = text.replace(/\n[ ]{0,3}((<(hr)\b([^<>])*?\/?>)[ \t]*(?=\n{2,}))/g, hashMatch);
  
              // Special case for standalone HTML comments:
  
              /*
              text = text.replace(/
                  \n\n                                            // Starting after a blank line
                  [ ]{0,3}                                        // attacklab: g_tab_width - 1
                  (                                               // save in $1
                      <!
                      (--(?:|(?:[^>-]|-[^>])(?:[^-]|-[^-])*)--)   // see http://www.w3.org/TR/html-markup/syntax.html#comments and http://meta.stackexchange.com/q/95256
                      >
                      [ \t]*
                      (?=\n{2,})                                  // followed by a blank line
                  )
              /g,hashMatch);
              */
              text = text.replace(/\n\n[ ]{0,3}(<!(--(?:|(?:[^>-]|-[^>])(?:[^-]|-[^-])*)--)>[ \t]*(?=\n{2,}))/g, hashMatch);
  
              // PHP and ASP-style processor instructions (<?...?> and <%...%>)
  
              /*
              text = text.replace(/
                  (?:
                      \n\n            // Starting after a blank line
                  )
                  (                   // save in $1
                      [ ]{0,3}        // attacklab: g_tab_width - 1
                      (?:
                          <([?%])     // $2
                          [^\r]*?
                          \2>
                      )
                      [ \t]*
                      (?=\n{2,})      // followed by a blank line
                  )
              /g,hashMatch);
              */
              text = text.replace(/(?:\n\n)([ ]{0,3}(?:<([?%])[^\r]*?\2>)[ \t]*(?=\n{2,}))/g, hashMatch);
  
              return text;
          }
  
          function hashBlock(text) {
              text = text.replace(/(^\n+|\n+$)/g, "");
              // Replace the element text with a marker ("~KxK" where x is its key)
              return "\n\n~K" + (g_html_blocks.push(text) - 1) + "K\n\n";
          }
  
          function hashMatch(wholeMatch, m1) {
              return hashBlock(m1);
          }
          
          var blockGamutHookCallback = function (t) { return _RunBlockGamut(t); }
  
          function _RunBlockGamut(text, doNotUnhash, doNotCreateParagraphs) {
              //
              // These are all the transformations that form block-level
              // tags like paragraphs, headers, and list items.
              //
              
              text = pluginHooks.preBlockGamut(text, blockGamutHookCallback);
              
              text = _DoHeaders(text);
  
              // Do Horizontal Rules:
              var replacement = "<hr />\n";
              text = text.replace(/^[ ]{0,2}([ ]?\*[ ]?){3,}[ \t]*$/gm, replacement);
              text = text.replace(/^[ ]{0,2}([ ]?-[ ]?){3,}[ \t]*$/gm, replacement);
              text = text.replace(/^[ ]{0,2}([ ]?_[ ]?){3,}[ \t]*$/gm, replacement);
  
              text = _DoLists(text);
              text = _DoCodeBlocks(text);
              text = _DoBlockQuotes(text);
              
              text = pluginHooks.postBlockGamut(text, blockGamutHookCallback);
  
              // We already ran _HashHTMLBlocks() before, in Markdown(), but that
              // was to escape raw HTML in the original Markdown source. This time,
              // we're escaping the markup we've just created, so that we don't wrap
              // <p> tags around block-level tags.
              text = _HashHTMLBlocks(text);
              
              text = _FormParagraphs(text, doNotUnhash, doNotCreateParagraphs);
  
              return text;
          }
  
          function _RunSpanGamut(text) {
              //
              // These are all the transformations that occur *within* block-level
              // tags like paragraphs, headers, and list items.
              //
  
              text = pluginHooks.preSpanGamut(text);
              
              text = _DoCodeSpans(text);
              text = _EscapeSpecialCharsWithinTagAttributes(text);
              text = _EncodeBackslashEscapes(text);
  
              // Process anchor and image tags. Images must come first,
              // because ![foo][f] looks like an anchor.
              text = _DoImages(text);
              text = _DoAnchors(text);
  
              // Make links out of things like `<http://example.com/>`
              // Must come after _DoAnchors(), because you can use < and >
              // delimiters in inline links like [this](<url>).
              text = _DoAutoLinks(text);
              
              text = text.replace(/~P/g, "://"); // put in place to prevent autolinking; reset now
              
              text = _EncodeAmpsAndAngles(text);
              text = _DoItalicsAndBold(text);
  
              // Do hard breaks:
              text = text.replace(/  +\n/g, " <br>\n");
              
              text = pluginHooks.postSpanGamut(text);
  
              return text;
          }
  
          function _EscapeSpecialCharsWithinTagAttributes(text) {
              //
              // Within tags -- meaning between < and > -- encode [\ ` * _] so they
              // don't conflict with their use in Markdown for code, italics and strong.
              //
  
              // Build a regex to find HTML tags and comments.  See Friedl's 
              // "Mastering Regular Expressions", 2nd Ed., pp. 200-201.
  
              // SE: changed the comment part of the regex
  
              var regex = /(<[a-z\/!$]("[^"]*"|'[^']*'|[^'">])*>|<!(--(?:|(?:[^>-]|-[^>])(?:[^-]|-[^-])*)--)>)/gi;
  
              text = text.replace(regex, function (wholeMatch) {
                  var tag = wholeMatch.replace(/(.)<\/?code>(?=.)/g, "$1`");
                  tag = escapeCharacters(tag, wholeMatch.charAt(1) == "!" ? "\\`*_/" : "\\`*_"); // also escape slashes in comments to prevent autolinking there -- http://meta.stackexchange.com/questions/95987
                  return tag;
              });
  
              return text;
          }
  
          function _DoAnchors(text) {
              
              if (text.indexOf("[") === -1)
                  return text;
              
              //
              // Turn Markdown link shortcuts into XHTML <a> tags.
              //
              //
              // First, handle reference-style links: [link text] [id]
              //
  
              /*
              text = text.replace(/
                  (                           // wrap whole match in $1
                      \[
                      (
                          (?:
                              \[[^\]]*\]      // allow brackets nested one level
                              |
                              [^\[]           // or anything else
                          )*
                      )
                      \]
  
                      [ ]?                    // one optional space
                      (?:\n[ ]*)?             // one optional newline followed by spaces
  
                      \[
                      (.*?)                   // id = $3
                      \]
                  )
                  ()()()()                    // pad remaining backreferences
              /g, writeAnchorTag);
              */
              text = text.replace(/(\[((?:\[[^\]]*\]|[^\[\]])*)\][ ]?(?:\n[ ]*)?\[(.*?)\])()()()()/g, writeAnchorTag);
  
              //
              // Next, inline-style links: [link text](url "optional title")
              //
  
              /*
              text = text.replace(/
                  (                           // wrap whole match in $1
                      \[
                      (
                          (?:
                              \[[^\]]*\]      // allow brackets nested one level
                              |
                              [^\[\]]         // or anything else
                          )*
                      )
                      \]
                      \(                      // literal paren
                      [ \t]*
                      ()                      // no id, so leave $3 empty
                      <?(                     // href = $4
                          (?:
                              \([^)]*\)       // allow one level of (correctly nested) parens (think MSDN)
                              |
                              [^()\s]
                          )*?
                      )>?                
                      [ \t]*
                      (                       // $5
                          (['"])              // quote char = $6
                          (.*?)               // Title = $7
                          \6                  // matching quote
                          [ \t]*              // ignore any spaces/tabs between closing quote and )
                      )?                      // title is optional
                      \)
                  )
              /g, writeAnchorTag);
              */
  
              text = text.replace(/(\[((?:\[[^\]]*\]|[^\[\]])*)\]\([ \t]*()<?((?:\([^)]*\)|[^()\s])*?)>?[ \t]*((['"])(.*?)\6[ \t]*)?\))/g, writeAnchorTag);
  
              //
              // Last, handle reference-style shortcuts: [link text]
              // These must come last in case you've also got [link test][1]
              // or [link test](/foo)
              //
  
              /*
              text = text.replace(/
                  (                   // wrap whole match in $1
                      \[
                      ([^\[\]]+)      // link text = $2; can't contain '[' or ']'
                      \]
                  )
                  ()()()()()          // pad rest of backreferences
              /g, writeAnchorTag);
              */
              text = text.replace(/(\[([^\[\]]+)\])()()()()()/g, writeAnchorTag);
  
              return text;
          }
  
          function writeAnchorTag(wholeMatch, m1, m2, m3, m4, m5, m6, m7) {
              if (m7 == undefined) m7 = "";
              var whole_match = m1;
              var link_text = m2.replace(/:\/\//g, "~P"); // to prevent auto-linking withing the link. will be converted back after the auto-linker runs
              var link_id = m3.toLowerCase();
              var url = m4;
              var title = m7;
  
              if (url == "") {
                  if (link_id == "") {
                      // lower-case and turn embedded newlines into spaces
                      link_id = link_text.toLowerCase().replace(/ ?\n/g, " ");
                  }
                  url = "#" + link_id;
  
                  if (g_urls.get(link_id) != undefined) {
                      url = g_urls.get(link_id);
                      if (g_titles.get(link_id) != undefined) {
                          title = g_titles.get(link_id);
                      }
                  }
                  else {
                      if (whole_match.search(/\(\s*\)$/m) > -1) {
                          // Special case for explicit empty url
                          url = "";
                      } else {
                          return whole_match;
                      }
                  }
              }
              url = attributeSafeUrl(url);
  
              var result = "<a href=\"" + url + "\"";
  
              if (title != "") {
                  title = attributeEncode(title);
                  title = escapeCharacters(title, "*_");
                  result += " title=\"" + title + "\"";
              }
  
              result += ">" + link_text + "</a>";
  
              return result;
          }
  
          function _DoImages(text) {
              
              if (text.indexOf("![") === -1)
                  return text;
              
              //
              // Turn Markdown image shortcuts into <img> tags.
              //
  
              //
              // First, handle reference-style labeled images: ![alt text][id]
              //
  
              /*
              text = text.replace(/
                  (                   // wrap whole match in $1
                      !\[
                      (.*?)           // alt text = $2
                      \]
  
                      [ ]?            // one optional space
                      (?:\n[ ]*)?     // one optional newline followed by spaces
  
                      \[
                      (.*?)           // id = $3
                      \]
                  )
                  ()()()()            // pad rest of backreferences
              /g, writeImageTag);
              */
              text = text.replace(/(!\[(.*?)\][ ]?(?:\n[ ]*)?\[(.*?)\])()()()()/g, writeImageTag);
  
              //
              // Next, handle inline images:  ![alt text](url "optional title")
              // Don't forget: encode * and _
  
              /*
              text = text.replace(/
                  (                   // wrap whole match in $1
                      !\[
                      (.*?)           // alt text = $2
                      \]
                      \s?             // One optional whitespace character
                      \(              // literal paren
                      [ \t]*
                      ()              // no id, so leave $3 empty
                      <?(\S+?)>?      // src url = $4
                      [ \t]*
                      (               // $5
                          (['"])      // quote char = $6
                          (.*?)       // title = $7
                          \6          // matching quote
                          [ \t]*
                      )?              // title is optional
                      \)
                  )
              /g, writeImageTag);
              */
              text = text.replace(/(!\[(.*?)\]\s?\([ \t]*()<?(\S+?)>?[ \t]*((['"])(.*?)\6[ \t]*)?\))/g, writeImageTag);
  
              return text;
          }
          
          function attributeEncode(text) {
              // unconditionally replace angle brackets here -- what ends up in an attribute (e.g. alt or title)
              // never makes sense to have verbatim HTML in it (and the sanitizer would totally break it)
              return text.replace(/>/g, "&gt;").replace(/</g, "&lt;").replace(/"/g, "&quot;").replace(/'/g, "&#39;");
          }
  
          function writeImageTag(wholeMatch, m1, m2, m3, m4, m5, m6, m7) {
              var whole_match = m1;
              var alt_text = m2;
              var link_id = m3.toLowerCase();
              var url = m4;
              var title = m7;
  
              if (!title) title = "";
  
              if (url == "") {
                  if (link_id == "") {
                      // lower-case and turn embedded newlines into spaces
                      link_id = alt_text.toLowerCase().replace(/ ?\n/g, " ");
                  }
                  url = "#" + link_id;
  
                  if (g_urls.get(link_id) != undefined) {
                      url = g_urls.get(link_id);
                      if (g_titles.get(link_id) != undefined) {
                          title = g_titles.get(link_id);
                      }
                  }
                  else {
                      return whole_match;
                  }
              }
              
              alt_text = escapeCharacters(attributeEncode(alt_text), "*_[]()");
              url = escapeCharacters(url, "*_");
              var result = "<img src=\"" + url + "\" alt=\"" + alt_text + "\"";
  
              // attacklab: Markdown.pl adds empty title attributes to images.
              // Replicate this bug.
  
              //if (title != "") {
              title = attributeEncode(title);
              title = escapeCharacters(title, "*_");
              result += " title=\"" + title + "\"";
              //}
  
              result += " />";
  
              return result;
          }
  
          function _DoHeaders(text) {
  
              // Setext-style headers:
              //  Header 1
              //  ========
              //  
              //  Header 2
              //  --------
              //
              text = text.replace(/^(.+)[ \t]*\n=+[ \t]*\n+/gm,
                  function (wholeMatch, m1) { return "<h1>" + _RunSpanGamut(m1) + "</h1>\n\n"; }
              );
  
              text = text.replace(/^(.+)[ \t]*\n-+[ \t]*\n+/gm,
                  function (matchFound, m1) { return "<h2>" + _RunSpanGamut(m1) + "</h2>\n\n"; }
              );
  
              // atx-style headers:
              //  # Header 1
              //  ## Header 2
              //  ## Header 2 with closing hashes ##
              //  ...
              //  ###### Header 6
              //
  
              /*
              text = text.replace(/
                  ^(\#{1,6})      // $1 = string of #'s
                  [ \t]*
                  (.+?)           // $2 = Header text
                  [ \t]*
                  \#*             // optional closing #'s (not counted)
                  \n+
              /gm, function() {...});
              */
  
              text = text.replace(/^(\#{1,6})[ \t]*(.+?)[ \t]*\#*\n+/gm,
                  function (wholeMatch, m1, m2) {
                      var h_level = m1.length;
                      return "<h" + h_level + ">" + _RunSpanGamut(m2) + "</h" + h_level + ">\n\n";
                  }
              );
  
              return text;
          }
  
          function _DoLists(text, isInsideParagraphlessListItem) {
              //
              // Form HTML ordered (numbered) and unordered (bulleted) lists.
              //
  
              // attacklab: add sentinel to hack around khtml/safari bug:
              // http://bugs.webkit.org/show_bug.cgi?id=11231
              text += "~0";
  
              // Re-usable pattern to match any entirel ul or ol list:
  
              /*
              var whole_list = /
                  (                                   // $1 = whole list
                      (                               // $2
                          [ ]{0,3}                    // attacklab: g_tab_width - 1
                          ([*+-]|\d+[.])              // $3 = first list item marker
                          [ \t]+
                      )
                      [^\r]+?
                      (                               // $4
                          ~0                          // sentinel for workaround; should be $
                          |
                          \n{2,}
                          (?=\S)
                          (?!                         // Negative lookahead for another list item marker
                              [ \t]*
                              (?:[*+-]|\d+[.])[ \t]+
                          )
                      )
                  )
              /g
              */
              var whole_list = /^(([ ]{0,3}([*+-]|\d+[.])[ \t]+)[^\r]+?(~0|\n{2,}(?=\S)(?![ \t]*(?:[*+-]|\d+[.])[ \t]+)))/gm;
              if (g_list_level) {
                  text = text.replace(whole_list, function (wholeMatch, m1, m2) {
                      var list = m1;
                      var list_type = (m2.search(/[*+-]/g) > -1) ? "ul" : "ol";
                      var first_number;
                      if (list_type === "ol")
                          first_number = parseInt(m2, 10)
  
                      var result = _ProcessListItems(list, list_type, isInsideParagraphlessListItem);
  
                      // Trim any trailing whitespace, to put the closing `</$list_type>`
                      // up on the preceding line, to get it past the current stupid
                      // HTML block parser. This is a hack to work around the terrible
                      // hack that is the HTML block parser.
                      result = result.replace(/\s+$/, "");
                      var opening = "<" + list_type;
                      if (first_number && first_number !== 1)
                          opening += " start=\"" + first_number + "\"";
                      result = opening + ">" + result + "</" + list_type + ">\n";
                      return result;
                  });
              } else {
                  whole_list = /(\n\n|^\n?)(([ ]{0,3}([*+-]|\d+[.])[ \t]+)[^\r]+?(~0|\n{2,}(?=\S)(?![ \t]*(?:[*+-]|\d+[.])[ \t]+)))/g;
                  text = text.replace(whole_list, function (wholeMatch, m1, m2, m3) {
                      var runup = m1;
                      var list = m2;
  
                      var list_type = (m3.search(/[*+-]/g) > -1) ? "ul" : "ol";
  
                      var first_number;
                      if (list_type === "ol")
                          first_number = parseInt(m3, 10)
  
                      var result = _ProcessListItems(list, list_type);
                      var opening = "<" + list_type;
                      if (first_number && first_number !== 1)
                          opening += " start=\"" + first_number + "\"";
  
                      result = runup + opening + ">\n" + result + "</" + list_type + ">\n";
                      return result;
                  });
              }
  
              // attacklab: strip sentinel
              text = text.replace(/~0/, "");
  
              return text;
          }
  
          var _listItemMarkers = { ol: "\\d+[.]", ul: "[*+-]" };
  
          function _ProcessListItems(list_str, list_type, isInsideParagraphlessListItem) {
              //
              //  Process the contents of a single ordered or unordered list, splitting it
              //  into individual list items.
              //
              //  list_type is either "ul" or "ol".
  
              // The $g_list_level global keeps track of when we're inside a list.
              // Each time we enter a list, we increment it; when we leave a list,
              // we decrement. If it's zero, we're not in a list anymore.
              //
              // We do this because when we're not inside a list, we want to treat
              // something like this:
              //
              //    I recommend upgrading to version
              //    8. Oops, now this line is treated
              //    as a sub-list.
              //
              // As a single paragraph, despite the fact that the second line starts
              // with a digit-period-space sequence.
              //
              // Whereas when we're inside a list (or sub-list), that line will be
              // treated as the start of a sub-list. What a kludge, huh? This is
              // an aspect of Markdown's syntax that's hard to parse perfectly
              // without resorting to mind-reading. Perhaps the solution is to
              // change the syntax rules such that sub-lists must start with a
              // starting cardinal number; e.g. "1." or "a.".
  
              g_list_level++;
  
              // trim trailing blank lines:
              list_str = list_str.replace(/\n{2,}$/, "\n");
  
              // attacklab: add sentinel to emulate \z
              list_str += "~0";
  
              // In the original attacklab showdown, list_type was not given to this function, and anything
              // that matched /[*+-]|\d+[.]/ would just create the next <li>, causing this mismatch:
              //
              //  Markdown          rendered by WMD        rendered by MarkdownSharp
              //  ------------------------------------------------------------------
              //  1. first          1. first               1. first
              //  2. second         2. second              2. second
              //  - third           3. third                   * third
              //
              // We changed this to behave identical to MarkdownSharp. This is the constructed RegEx,
              // with {MARKER} being one of \d+[.] or [*+-], depending on list_type:
          
              /*
              list_str = list_str.replace(/
                  (^[ \t]*)                       // leading whitespace = $1
                  ({MARKER}) [ \t]+               // list marker = $2
                  ([^\r]+?                        // list item text   = $3
                      (\n+)
                  )
                  (?=
                      (~0 | \2 ({MARKER}) [ \t]+)
                  )
              /gm, function(){...});
              */
  
              var marker = _listItemMarkers[list_type];
              var re = new RegExp("(^[ \\t]*)(" + marker + ")[ \\t]+([^\\r]+?(\\n+))(?=(~0|\\1(" + marker + ")[ \\t]+))", "gm");
              var last_item_had_a_double_newline = false;
              list_str = list_str.replace(re,
                  function (wholeMatch, m1, m2, m3) {
                      var item = m3;
                      var leading_space = m1;
                      var ends_with_double_newline = /\n\n$/.test(item);
                      var contains_double_newline = ends_with_double_newline || item.search(/\n{2,}/) > -1;
                      
                      var loose = contains_double_newline || last_item_had_a_double_newline;
                      item = _RunBlockGamut(_Outdent(item), /* doNotUnhash = */true, /* doNotCreateParagraphs = */ !loose);
                      
                      last_item_had_a_double_newline = ends_with_double_newline;
                      return "<li>" + item + "</li>\n";
                  }
              );
  
              // attacklab: strip sentinel
              list_str = list_str.replace(/~0/g, "");
  
              g_list_level--;
              return list_str;
          }
  
          function _DoCodeBlocks(text) {
              //
              //  Process Markdown `<pre><code>` blocks.
              //  
  
              /*
              text = text.replace(/
                  (?:\n\n|^)
                  (                               // $1 = the code block -- one or more lines, starting with a space/tab
                      (?:
                          (?:[ ]{4}|\t)           // Lines must start with a tab or a tab-width of spaces - attacklab: g_tab_width
                          .*\n+
                      )+
                  )
                  (\n*[ ]{0,3}[^ \t\n]|(?=~0))    // attacklab: g_tab_width
              /g ,function(){...});
              */
  
              // attacklab: sentinel workarounds for lack of \A and \Z, safari\khtml bug
              text += "~0";
  
              text = text.replace(/(?:\n\n|^\n?)((?:(?:[ ]{4}|\t).*\n+)+)(\n*[ ]{0,3}[^ \t\n]|(?=~0))/g,
                  function (wholeMatch, m1, m2) {
                      var codeblock = m1;
                      var nextChar = m2;
  
                      codeblock = _EncodeCode(_Outdent(codeblock));
                      codeblock = _Detab(codeblock);
                      codeblock = codeblock.replace(/^\n+/g, ""); // trim leading newlines
                      codeblock = codeblock.replace(/\n+$/g, ""); // trim trailing whitespace
  
                      codeblock = "<pre><code>" + codeblock + "\n</code></pre>";
  
                      return "\n\n" + codeblock + "\n\n" + nextChar;
                  }
              );
  
              // attacklab: strip sentinel
              text = text.replace(/~0/, "");
  
              return text;
          }
  
          function _DoCodeSpans(text) {
              //
              // * Backtick quotes are used for <code></code> spans.
              // 
              // * You can use multiple backticks as the delimiters if you want to
              //   include literal backticks in the code span. So, this input:
              //     
              //      Just type ``foo `bar` baz`` at the prompt.
              //     
              //   Will translate to:
              //     
              //      <p>Just type <code>foo `bar` baz</code> at the prompt.</p>
              //     
              //   There's no arbitrary limit to the number of backticks you
              //   can use as delimters. If you need three consecutive backticks
              //   in your code, use four for delimiters, etc.
              //
              // * You can use spaces to get literal backticks at the edges:
              //     
              //      ... type `` `bar` `` ...
              //     
              //   Turns to:
              //     
              //      ... type <code>`bar`</code> ...
              //
  
              /*
              text = text.replace(/
                  (^|[^\\`])      // Character before opening ` can't be a backslash or backtick
                  (`+)            // $2 = Opening run of `
                  (?!`)           // and no more backticks -- match the full run
                  (               // $3 = The code block
                      [^\r]*?
                      [^`]        // attacklab: work around lack of lookbehind
                  )
                  \2              // Matching closer
                  (?!`)
              /gm, function(){...});
              */
  
              text = text.replace(/(^|[^\\`])(`+)(?!`)([^\r]*?[^`])\2(?!`)/gm,
                  function (wholeMatch, m1, m2, m3, m4) {
                      var c = m3;
                      c = c.replace(/^([ \t]*)/g, ""); // leading whitespace
                      c = c.replace(/[ \t]*$/g, ""); // trailing whitespace
                      c = _EncodeCode(c);
                      c = c.replace(/:\/\//g, "~P"); // to prevent auto-linking. Not necessary in code *blocks*, but in code spans. Will be converted back after the auto-linker runs.
                      return m1 + "<code>" + c + "</code>";
                  }
              );
  
              return text;
          }
  
          function _EncodeCode(text) {
              //
              // Encode/escape certain characters inside Markdown code runs.
              // The point is that in code, these characters are literals,
              // and lose their special Markdown meanings.
              //
              // Encode all ampersands; HTML entities are not
              // entities within a Markdown code span.
              text = text.replace(/&/g, "&amp;");
  
              // Do the angle bracket song and dance:
              text = text.replace(/</g, "&lt;");
              text = text.replace(/>/g, "&gt;");
  
              // Now, escape characters that are magic in Markdown:
              text = escapeCharacters(text, "\*_{}[]\\", false);
  
              // jj the line above breaks this:
              //---
  
              //* Item
  
              //   1. Subitem
  
              //            special char: *
              //---
  
              return text;
          }
  
          function _DoItalicsAndBoldStrict(text) {
  
              if (text.indexOf("*") === -1 && text.indexOf("_") === - 1)
                  return text;
              
              text = asciify(text);
          
              // <strong> must go first:
              
              // (^|[\W_])           Start with a non-letter or beginning of string. Store in \1.
              // (?:(?!\1)|(?=^))    Either the next character is *not* the same as the previous,
              //                     or we started at the end of the string (in which case the previous
              //                     group had zero width, so we're still there). Because the next
              //                     character is the marker, this means that if there are e.g. multiple
              //                     underscores in a row, we can only match the left-most ones (which
              //                     prevents foo___bar__ from getting bolded)
              // (\*|_)              The marker character itself, asterisk or underscore. Store in \2.
              // \2                  The marker again, since bold needs two.
              // (?=\S)              The first bolded character cannot be a space.
              // ([^\r]*?\S)         The actual bolded string. At least one character, and it cannot *end*
              //                     with a space either. Note that like in many other places, [^\r] is
              //                     just a workaround for JS' lack of single-line regexes; it's equivalent
              //                     to a . in an /s regex, because the string cannot contain any \r (they
              //                     are removed in the normalizing step).
              // \2\2                The marker character, twice -- end of bold.
              // (?!\2)              Not followed by another marker character (ensuring that we match the
              //                     rightmost two in a longer row)...
              // (?=[\W_]|$)         ...but by any other non-word character or the end of string.
              text = text.replace(/(^|[\W_])(?:(?!\1)|(?=^))(\*|_)\2(?=\S)([^\r]*?\S)\2\2(?!\2)(?=[\W_]|$)/g,
              "$1<strong>$3</strong>");
  
              // This is almost identical to the <strong> regex, except 1) there's obviously just one marker
              // character, and 2) the italicized string cannot contain the marker character.
              text = text.replace(/(^|[\W_])(?:(?!\1)|(?=^))(\*|_)(?=\S)((?:(?!\2)[^\r])*?\S)\2(?!\2)(?=[\W_]|$)/g,
              "$1<em>$3</em>");
  
              return deasciify(text);
          }
  
          function _DoItalicsAndBold_AllowIntrawordWithAsterisk(text) {
              
              if (text.indexOf("*") === -1 && text.indexOf("_") === - 1)
                  return text;
              
              text = asciify(text);
          
              // <strong> must go first:
              // (?=[^\r][*_]|[*_])               Optimization only, to find potentially relevant text portions faster. Minimally slower in Chrome, but much faster in IE.
              // (                                Store in \1. This is the last character before the delimiter
              //     ^                            Either we're at the start of the string (i.e. there is no last character)...
              //     |                            ... or we allow one of the following:
              //     (?=                          (lookahead; we're not capturing this, just listing legal possibilities)
              //         \W__                     If the delimiter is __, then this last character must be non-word non-underscore (extra-word emphasis only)
              //         |
              //         (?!\*)[\W_]\*\*          If the delimiter is **, then this last character can be non-word non-asterisk (extra-word emphasis)...
              //         |
              //         \w\*\*\w                 ...or it can be word/underscore, but only if the first bolded character is such a character as well (intra-word emphasis)
              //     )
              //     [^\r]                        actually capture the character (can't use `.` since it could be \n)
              // )
              // (\*\*|__)                        Store in \2: the actual delimiter
              // (?!\2)                           not followed by the delimiter again (at most one more asterisk/underscore is allowed)
              // (?=\S)                           the first bolded character can't be a space
              // (                                Store in \3: the bolded string
              //                                  
              //     (?:|                         Look at all bolded characters except for the last one. Either that's empty, meaning only a single character was bolded...
              //       [^\r]*?                    ... otherwise take arbitrary characters, minimally matching; that's all bolded characters except for the last *two*
              //       (?!\2)                       the last two characters cannot be the delimiter itself (because that would mean four underscores/asterisks in a row)
              //       [^\r]                        capture the next-to-last bolded character
              //     )
              //     (?=                          lookahead at the very last bolded char and what comes after
              //         \S_                      for underscore-bolding, it can be any non-space
              //         |
              //         \w                       for asterisk-bolding (otherwise the previous alternative would've matched, since \w implies \S), either the last char is word/underscore...
              //         |
              //         \S\*\*(?:[\W_]|$)        ... or it's any other non-space, but in that case the character *after* the delimiter may not be a word character
              //     )
              //     .                            actually capture the last character (can use `.` this time because the lookahead ensures \S in all cases)
              // )
              // (?=                              lookahead; list the legal possibilities for the closing delimiter and its following character
              //     __(?:\W|$)                   for underscore-bolding, the following character (if any) must be non-word non-underscore
              //     |
              //     \*\*(?:[^*]|$)               for asterisk-bolding, any non-asterisk is allowed (note we already ensured above that it's not a word character if the last bolded character wasn't one)
              // )
              // \2                               actually capture the closing delimiter (and make sure that it matches the opening one)
            
              text = text.replace(/(?=[^\r][*_]|[*_])(^|(?=\W__|(?!\*)[\W_]\*\*|\w\*\*\w)[^\r])(\*\*|__)(?!\2)(?=\S)((?:|[^\r]*?(?!\2)[^\r])(?=\S_|\w|\S\*\*(?:[\W_]|$)).)(?=__(?:\W|$)|\*\*(?:[^*]|$))\2/g,
              "$1<strong>$3</strong>");
  
              // now <em>:
              // (?=[^\r][*_]|[*_])               Optimization, see above.
              // (                                Store in \1. This is the last character before the delimiter
              //     ^                            Either we're at the start of the string (i.e. there is no last character)...
              //     |                            ... or we allow one of the following:
              //     (?=                          (lookahead; we're not capturing this, just listing legal possibilities)
              //         \W_                      If the delimiter is _, then this last character must be non-word non-underscore (extra-word emphasis only)
              //         |
              //         (?!\*)                   otherwise, we list two possiblities for * as the delimiter; in either case, the last characters cannot be an asterisk itself
              //         (?:
              //             [\W_]\*              this last character can be non-word (extra-word emphasis)...
              //             |
              //             \D\*(?=\w)\D         ...or it can be word (otherwise the first alternative would've matched), but only if
              //                                      a) the first italicized character is such a character as well (intra-word emphasis), and
              //                                      b) neither character on either side of the asterisk is a digit            
              //         )
              //     )
              //     [^\r]                        actually capture the character (can't use `.` since it could be \n)
              // )
              // (\*|_)                           Store in \2: the actual delimiter
              // (?!\2\2\2)                       not followed by more than two more instances of the delimiter
              // (?=\S)                           the first italicized character can't be a space
              // (                                Store in \3: the italicized string
              //     (?:(?!\2)[^\r])*?            arbitrary characters except for the delimiter itself, minimally matching
              //     (?=                          lookahead at the very last italicized char and what comes after
              //         [^\s_]_                  for underscore-italicizing, it can be any non-space non-underscore
              //         |
              //         (?=\w)\D\*\D             for asterisk-italicizing, either the last char is word/underscore *and* neither character on either side of the asterisk is a digit...
              //         |
              //         [^\s*]\*(?:[\W_]|$)      ... or that last char is any other non-space non-asterisk, but then the character after the delimiter (if any) must be non-word
              //     )
              //     .                            actually capture the last character (can use `.` this time because the lookahead ensures \S in all cases)
              // )
              // (?=                              lookahead; list the legal possibilities for the closing delimiter and its following character
              //     _(?:\W|$)                    for underscore-italicizing, the following character (if any) must be non-word non-underscore
              //     |
              //     \*(?:[^*]|$)                 for asterisk-italicizing, any non-asterisk is allowed; all other restrictions have already been ensured in the previous lookahead
              // )
              // \2                               actually capture the closing delimiter (and make sure that it matches the opening one)
  
              text = text.replace(/(?=[^\r][*_]|[*_])(^|(?=\W_|(?!\*)(?:[\W_]\*|\D\*(?=\w)\D))[^\r])(\*|_)(?!\2\2\2)(?=\S)((?:(?!\2)[^\r])*?(?=[^\s_]_|(?=\w)\D\*\D|[^\s*]\*(?:[\W_]|$)).)(?=_(?:\W|$)|\*(?:[^*]|$))\2/g,
              "$1<em>$3</em>");
              
              return deasciify(text);
          }        
  
          
          function _DoBlockQuotes(text) {
  
              /*
              text = text.replace(/
                  (                           // Wrap whole match in $1
                      (
                          ^[ \t]*>[ \t]?      // '>' at the start of a line
                          .+\n                // rest of the first line
                          (.+\n)*             // subsequent consecutive lines
                          \n*                 // blanks
                      )+
                  )
              /gm, function(){...});
              */
  
              text = text.replace(/((^[ \t]*>[ \t]?.+\n(.+\n)*\n*)+)/gm,
                  function (wholeMatch, m1) {
                      var bq = m1;
  
                      // attacklab: hack around Konqueror 3.5.4 bug:
                      // "----------bug".replace(/^-/g,"") == "bug"
  
                      bq = bq.replace(/^[ \t]*>[ \t]?/gm, "~0"); // trim one level of quoting
  
                      // attacklab: clean up hack
                      bq = bq.replace(/~0/g, "");
  
                      bq = bq.replace(/^[ \t]+$/gm, "");     // trim whitespace-only lines
                      bq = _RunBlockGamut(bq);             // recurse
  
                      bq = bq.replace(/(^|\n)/g, "$1  ");
                      // These leading spaces screw with <pre> content, so we need to fix that:
                      bq = bq.replace(
                              /(\s*<pre>[^\r]+?<\/pre>)/gm,
                          function (wholeMatch, m1) {
                              var pre = m1;
                              // attacklab: hack around Konqueror 3.5.4 bug:
                              pre = pre.replace(/^  /mg, "~0");
                              pre = pre.replace(/~0/g, "");
                              return pre;
                          });
  
                      return hashBlock("<blockquote>\n" + bq + "\n</blockquote>");
                  }
              );
              return text;
          }
  
          function _FormParagraphs(text, doNotUnhash, doNotCreateParagraphs) {
              //
              //  Params:
              //    $text - string to process with html <p> tags
              //
  
              // Strip leading and trailing lines:
              text = text.replace(/^\n+/g, "");
              text = text.replace(/\n+$/g, "");
  
              var grafs = text.split(/\n{2,}/g);
              var grafsOut = [];
              
              var markerRe = /~K(\d+)K/;
  
              //
              // Wrap <p> tags.
              //
              var end = grafs.length;
              for (var i = 0; i < end; i++) {
                  var str = grafs[i];
  
                  // if this is an HTML marker, copy it
                  if (markerRe.test(str)) {
                      grafsOut.push(str);
                  }
                  else if (/\S/.test(str)) {
                      str = _RunSpanGamut(str);
                      str = str.replace(/^([ \t]*)/g, doNotCreateParagraphs ? "" : "<p>");
                      if (!doNotCreateParagraphs)
                          str += "</p>"
                      grafsOut.push(str);
                  }
  
              }
              //
              // Unhashify HTML blocks
              //
              if (!doNotUnhash) {
                  end = grafsOut.length;
                  for (var i = 0; i < end; i++) {
                      var foundAny = true;
                      while (foundAny) { // we may need several runs, since the data may be nested
                          foundAny = false;
                          grafsOut[i] = grafsOut[i].replace(/~K(\d+)K/g, function (wholeMatch, id) {
                              foundAny = true;
                              return g_html_blocks[id];
                          });
                      }
                  }
              }
              return grafsOut.join("\n\n");
          }
  
          function _EncodeAmpsAndAngles(text) {
              // Smart processing for ampersands and angle brackets that need to be encoded.
  
              // Ampersand-encoding based entirely on Nat Irons's Amputator MT plugin:
              //   http://bumppo.net/projects/amputator/
              text = text.replace(/&(?!#?[xX]?(?:[0-9a-fA-F]+|\w+);)/g, "&amp;");
  
              // Encode naked <'s
              text = text.replace(/<(?![a-z\/?!]|~D)/gi, "&lt;");
  
              return text;
          }
  
          function _EncodeBackslashEscapes(text) {
              //
              //   Parameter:  String.
              //   Returns:    The string, with after processing the following backslash
              //               escape sequences.
              //
  
              // attacklab: The polite way to do this is with the new
              // escapeCharacters() function:
              //
              //     text = escapeCharacters(text,"\\",true);
              //     text = escapeCharacters(text,"`*_{}[]()>#+-.!",true);
              //
              // ...but we're sidestepping its use of the (slow) RegExp constructor
              // as an optimization for Firefox.  This function gets called a LOT.
  
              text = text.replace(/\\(\\)/g, escapeCharacters_callback);
              text = text.replace(/\\([`*_{}\[\]()>#+-.!])/g, escapeCharacters_callback);
              return text;
          }
  
          var charInsideUrl = "[-A-Z0-9+&@#/%?=~_|[\\]()!:,.;]",
              charEndingUrl = "[-A-Z0-9+&@#/%=~_|[\\])]",
              autoLinkRegex = new RegExp("(=\"|<)?\\b(https?|ftp)(://" + charInsideUrl + "*" + charEndingUrl + ")(?=$|\\W)", "gi"),
              endCharRegex = new RegExp(charEndingUrl, "i");
  
          function handleTrailingParens(wholeMatch, lookbehind, protocol, link) {
              if (lookbehind)
                  return wholeMatch;
              if (link.charAt(link.length - 1) !== ")")
                  return "<" + protocol + link + ">";
              var parens = link.match(/[()]/g);
              var level = 0;
              for (var i = 0; i < parens.length; i++) {
                  if (parens[i] === "(") {
                      if (level <= 0)
                          level = 1;
                      else
                          level++;
                  }
                  else {
                      level--;
                  }
              }
              var tail = "";
              if (level < 0) {
                  var re = new RegExp("\\){1," + (-level) + "}$");
                  link = link.replace(re, function (trailingParens) {
                      tail = trailingParens;
                      return "";
                  });
              }
              if (tail) {
                  var lastChar = link.charAt(link.length - 1);
                  if (!endCharRegex.test(lastChar)) {
                      tail = lastChar + tail;
                      link = link.substr(0, link.length - 1);
                  }
              }
              return "<" + protocol + link + ">" + tail;
          }
          
          function _DoAutoLinks(text) {
  
              // note that at this point, all other URL in the text are already hyperlinked as <a href=""></a>
              // *except* for the <http://www.foo.com> case
  
              // automatically add < and > around unadorned raw hyperlinks
              // must be preceded by a non-word character (and not by =" or <) and followed by non-word/EOF character
              // simulating the lookbehind in a consuming way is okay here, since a URL can neither and with a " nor
              // with a <, so there is no risk of overlapping matches.
              text = text.replace(autoLinkRegex, handleTrailingParens);
  
              //  autolink anything like <http://example.com>
              
  
              var replacer = function (wholematch, m1) {
                  var url = attributeSafeUrl(m1);
                  
                  return "<a href=\"" + url + "\">" + pluginHooks.plainLinkText(m1) + "</a>";
              };
              text = text.replace(/<((https?|ftp):[^'">\s]+)>/gi, replacer);
  
              // Email addresses: <address@domain.foo>
              /*
              text = text.replace(/
                  <
                  (?:mailto:)?
                  (
                      [-.\w]+
                      \@
                      [-a-z0-9]+(\.[-a-z0-9]+)*\.[a-z]+
                  )
                  >
              /gi, _DoAutoLinks_callback());
              */
  
              /* disabling email autolinking, since we don't do that on the server, either
              text = text.replace(/<(?:mailto:)?([-.\w]+\@[-a-z0-9]+(\.[-a-z0-9]+)*\.[a-z]+)>/gi,
                  function(wholeMatch,m1) {
                      return _EncodeEmailAddress( _UnescapeSpecialChars(m1) );
                  }
              );
              */
              return text;
          }
  
          function _UnescapeSpecialChars(text) {
              //
              // Swap back in all the special characters we've hidden.
              //
              text = text.replace(/~E(\d+)E/g,
                  function (wholeMatch, m1) {
                      var charCodeToReplace = parseInt(m1);
                      return String.fromCharCode(charCodeToReplace);
                  }
              );
              return text;
          }
  
          function _Outdent(text) {
              //
              // Remove one level of line-leading tabs or spaces
              //
  
              // attacklab: hack around Konqueror 3.5.4 bug:
              // "----------bug".replace(/^-/g,"") == "bug"
  
              text = text.replace(/^(\t|[ ]{1,4})/gm, "~0"); // attacklab: g_tab_width
  
              // attacklab: clean up hack
              text = text.replace(/~0/g, "")
  
              return text;
          }
  
          function _Detab(text) {
              if (!/\t/.test(text))
                  return text;
  
              var spaces = ["    ", "   ", "  ", " "],
              skew = 0,
              v;
  
              return text.replace(/[\n\t]/g, function (match, offset) {
                  if (match === "\n") {
                      skew = offset + 1;
                      return match;
                  }
                  v = (offset - skew) % 4;
                  skew = offset + 1;
                  return spaces[v];
              });
          }
  
          //
          //  attacklab: Utility functions
          //
  
          function attributeSafeUrl(url) {
              url = attributeEncode(url);
              url = escapeCharacters(url, "*_:()[]")
              return url;
          }
  
          function escapeCharacters(text, charsToEscape, afterBackslash) {
              // First we have to escape the escape characters so that
              // we can build a character class out of them
              var regexString = "([" + charsToEscape.replace(/([\[\]\\])/g, "\\$1") + "])";
  
              if (afterBackslash) {
                  regexString = "\\\\" + regexString;
              }
  
              var regex = new RegExp(regexString, "g");
              text = text.replace(regex, escapeCharacters_callback);
  
              return text;
          }
  
  
          function escapeCharacters_callback(wholeMatch, m1) {
              var charCodeToEscape = m1.charCodeAt(0);
              return "~E" + charCodeToEscape + "E";
          }
  
      }; // end of the Markdown.Converter constructor
  
  })();