git.fiddlerwoaroof.com
js/showdown.js
489b3d20
 //
 // showdown.js -- A javascript port of Markdown.
 //
 // Copyright (c) 2007 John Fraser.
 //
 // Original Markdown Copyright (c) 2004-2005 John Gruber
 //   <http://daringfireball.net/projects/markdown/>
 //
 // Redistributable under a BSD-style open source license.
 // See license.txt for more information.
 //
 // The full source distribution is at:
 //
 //				A A L
 //				T C A
 //				T K B
 //
 //   <http://www.attacklab.net/>
 //
 
 //
 // 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.
 //
 
 
 //
 // Showdown usage:
 //
 //   var text = "Markdown *rocks*.";
 //
 //   var converter = new Showdown.converter();
 //   var html = converter.makeHtml(text);
 //
 //   alert(html);
 //
 // Note: move the sample code to the bottom of this
 // file before uncommenting it.
 //
 
 
 //
 // Showdown namespace
 //
 var Showdown = { extensions: {} };
 
 //
 // forEach
 //
 var forEach = Showdown.forEach = function(obj, callback) {
 	if (typeof obj.forEach === 'function') {
 		obj.forEach(callback);
 	} else {
 		var i, len = obj.length;
 		for (i = 0; i < len; i++) {
 			callback(obj[i], i, obj);
 		}
 	}
 };
 
 //
 // Standard extension naming
 //
 var stdExtName = function(s) {
 	return s.replace(/[_-]||\s/g, '').toLowerCase();
 };
 
 //
 // converter
 //
 // Wraps all "globals" so that the only thing
 // exposed is makeHtml().
 //
 Showdown.converter = function(converter_options) {
 
 //
 // Globals:
 //
 
 // 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 = 0;
 
 // Global extensions
 var g_lang_extensions = [];
 var g_output_modifiers = [];
 
 
 //
 // Automatic Extension Loading (node only):
 //
 
 if (typeof module !== 'undefind' && typeof exports !== 'undefined' && typeof require !== 'undefind') {
 	var fs = require('fs');
 
 	if (fs) {
 		// Search extensions folder
 		var extensions = fs.readdirSync((__dirname || '.')+'/extensions').filter(function(file){
 			return ~file.indexOf('.js');
 		}).map(function(file){
 			return file.replace(/\.js$/, '');
 		});
 		// Load extensions into Showdown namespace
 		Showdown.forEach(extensions, function(ext){
 			var name = stdExtName(ext);
 			Showdown.extensions[name] = require('./extensions/' + ext);
 		});
 	}
 }
 
 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.
 //
 
 	// Clear the global hashes. If we don't clear these, you get conflicts
 	// from other articles when generating a page which contains more than
 	// one article (e.g. an index page that shows the N most recent
 	// articles):
 	g_urls = {};
 	g_titles = {};
 	g_html_blocks = [];
 
 	// 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,"");
 
 	// Run language extensions
 	Showdown.forEach(g_lang_extensions, function(x){
 		text = _ExecuteExtension(x, text);
 	});
 
 	// Handle github codeblocks prior to running HashHTML so that
 	// HTML contained within the codeblock gets escaped propertly
 	text = _DoGithubCodeBlocks(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,"~");
 
 	// Run output modifiers
 	Showdown.forEach(g_output_modifiers, function(x){
 		text = _ExecuteExtension(x, text);
 	});
 
 	return text;
 };
 //
 // Options:
 //
 
 // Parse extensions options into separate arrays
 if (converter_options && converter_options.extensions) {
 
   var self = this;
 
 	// Iterate over each plugin
 	Showdown.forEach(converter_options.extensions, function(plugin){
 
 		// Assume it's a bundled plugin if a string is given
 		if (typeof plugin === 'string') {
 			plugin = Showdown.extensions[stdExtName(plugin)];
 		}
 
 		if (typeof plugin === 'function') {
 			// Iterate over each extension within that plugin
 			Showdown.forEach(plugin(self), function(ext){
 				// Sort extensions by type
 				if (ext.type) {
 					if (ext.type === 'language' || ext.type === 'lang') {
 						g_lang_extensions.push(ext);
 					} else if (ext.type === 'output' || ext.type === 'html') {
 						g_output_modifiers.push(ext);
 					}
 				} else {
 					// Assume language extension
 					g_output_modifiers.push(ext);
 				}
 			});
 		} else {
 			throw "Extension '" + plugin + "' could not be loaded.  It was either not found or is not a valid extension.";
 		}
 	});
 }
 
 
 var _ExecuteExtension = function(ext, text) {
 	if (ext.regex) {
 		var re = new RegExp(ext.regex, 'g');
 		return text.replace(re, ext.replace);
 	} else if (ext.filter) {
 		return ext.filter(text);
 	}
 };
 
 var _StripLinkDefinitions = function(text) {
 //
 // Strips link definitions from text, stores the URLs and titles in
 // hash references.
 //
 
 	// Link defs are in the form: ^[id]: url "optional title"
 
 	/*
 		var text = text.replace(/
 				^[ ]{0,3}\[(.+)\]:  // id = $1  attacklab: g_tab_width - 1
 				  [ \t]*
 				  \n?				// maybe *one* newline
 				  [ \t]*
 				<?(\S+?)>?			// url = $2
 				  [ \t]*
 				  \n?				// maybe one newline
 				  [ \t]*
 				(?:
 				  (\n*)				// any lines skipped = $3 attacklab: lookbehind removed
 				  ["(]
 				  (.+?)				// title = $4
 				  [")]
 				  [ \t]*
 				)?					// title is optional
 				(?:\n+|$)
 			  /gm,
 			  function(){...});
 	*/
 
 	// attacklab: sentinel workarounds for lack of \A and \Z, safari\khtml bug
 	text += "~0";
 
 	text = text.replace(/^[ ]{0,3}\[(.+)\]:[ \t]*\n?[ \t]*<?(\S+?)>?[ \t]*\n?[ \t]*(?:(\n*)["(](.+?)[")][ \t]*)?(?:\n+|(?=~0))/gm,
 		function (wholeMatch,m1,m2,m3,m4) {
 			m1 = m1.toLowerCase();
 			g_urls[m1] = _EncodeAmpsAndAngles(m2);  // Link IDs are case-insensitive
 			if (m3) {
 				// Oops, found blank lines, so it's not a title.
 				// Put back the parenthetical statement we stole.
 				return m3+m4;
 			} else if (m4) {
 				g_titles[m1] = m4.replace(/"/g,"&quot;");
 			}
 
 			// Completely remove the definition from the text
 			return "";
 		}
 	);
 
 	// attacklab: strip sentinel
 	text = text.replace(/~0/,"");
 
 	return text;
 }
 
 
 var _HashHTMLBlocks = function(text) {
 	// attacklab: Double up blank lines to reduce lookaround
 	text = text.replace(/\n/g,"\n\n");
 
 	// 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|style|section|header|footer|nav|article|aside";
 	var block_tags_b = "p|div|h[1-6]|blockquote|pre|table|dl|ol|ul|script|noscript|form|fieldset|iframe|math|style|section|header|footer|nav|article|aside";
 
 	// 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.
 	/*
 		var 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,hashElement);
 
 	//
 	// Now match more liberally, simply from `\n<tag>` to `</tag>\n`
 	//
 
 	/*
 		var 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|style|section|header|footer|nav|article|aside)\b[^\r]*?<\/\2>[ \t]*(?=\n+)\n)/gm,hashElement);
 
 	// Special case just for <hr />. It was easier to make a special case than
 	// to make the other regex more complicated.
 
 	/*
 		text = text.replace(/
 		(						// save in $1
 			\n\n				// Starting after a blank line
 			[ ]{0,3}
 			(<(hr)				// start tag = $2
 			\b					// word break
 			([^<>])*?			//
 			\/?>)				// the matching end tag
 			[ \t]*
 			(?=\n{2,})			// followed by a blank line
 		)
 		/g,hashElement);
 	*/
 	text = text.replace(/(\n[ ]{0,3}(<(hr)\b([^<>])*?\/?>)[ \t]*(?=\n{2,}))/g,hashElement);
 
 	// Special case for standalone HTML comments:
 
 	/*
 		text = text.replace(/
 		(						// save in $1
 			\n\n				// Starting after a blank line
 			[ ]{0,3}			// attacklab: g_tab_width - 1
 			<!
 			(--[^\r]*?--\s*)+
 			>
 			[ \t]*
 			(?=\n{2,})			// followed by a blank line
 		)
 		/g,hashElement);
 	*/
 	text = text.replace(/(\n\n[ ]{0,3}<!(--[^\r]*?--\s*)+>[ \t]*(?=\n{2,}))/g,hashElement);
 
 	// 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,hashElement);
 	*/
 	text = text.replace(/(?:\n\n)([ ]{0,3}(?:<([?%])[^\r]*?\2>)[ \t]*(?=\n{2,}))/g,hashElement);
 
 	// attacklab: Undo double lines (see comment at top of this function)
 	text = text.replace(/\n\n/g,"\n");
 	return text;
 }
 
 var hashElement = function(wholeMatch,m1) {
 	var blockText = m1;
 
 	// Undo double lines
 	blockText = blockText.replace(/\n\n/g,"\n");
 	blockText = blockText.replace(/^\n/,"");
 
 	// strip trailing blank lines
 	blockText = blockText.replace(/\n+$/g,"");
 
 	// Replace the element text with a marker ("~KxK" where x is its key)
 	blockText = "\n\n~K" + (g_html_blocks.push(blockText)-1) + "K\n\n";
 
 	return blockText;
 };
 
 var _RunBlockGamut = function(text) {
 //
 // These are all the transformations that form block-level
 // tags like paragraphs, headers, and list items.
 //
 	text = _DoHeaders(text);
 
 	// Do Horizontal Rules:
 	var key = hashBlock("<hr />");
 	text = text.replace(/^[ ]{0,2}([ ]?\*[ ]?){3,}[ \t]*$/gm,key);
 	text = text.replace(/^[ ]{0,2}([ ]?\-[ ]?){3,}[ \t]*$/gm,key);
 	text = text.replace(/^[ ]{0,2}([ ]?\_[ ]?){3,}[ \t]*$/gm,key);
 
 	text = _DoLists(text);
 	text = _DoCodeBlocks(text);
 	text = _DoBlockQuotes(text);
 
 	// 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);
 
 	return text;
 };
 
 
 var _RunSpanGamut = function(text) {
 //
 // These are all the transformations that occur *within* block-level
 // tags like paragraphs, headers, and list items.
 //
 
 	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 = _EncodeAmpsAndAngles(text);
 	text = _DoItalicsAndBold(text);
 
 	// Do hard breaks:
 	text = text.replace(/  +\n/g," <br />\n");
 
 	return text;
 }
 
 var _EscapeSpecialCharsWithinTagAttributes = function(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.
 	var regex = /(<[a-z\/!$]("[^"]*"|'[^']*'|[^'">])*>|<!(--.*?--\s*)+>)/gi;
 
 	text = text.replace(regex, function(wholeMatch) {
 		var tag = wholeMatch.replace(/(.)<\/?code>(?=.)/g,"$1`");
 		tag = escapeCharacters(tag,"\\`*_");
 		return tag;
 	});
 
 	return text;
 }
 
 var _DoAnchors = function(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,_DoAnchors_callback);
 	*/
 	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
 				)
 			)
 			\]
 			\(						// literal paren
 			[ \t]*
 			()						// no id, so leave $3 empty
 			<?(.*?)>?				// href = $4
 			[ \t]*
 			(						// $5
 				(['"])				// quote char = $6
 				(.*?)				// Title = $7
 				\6					// matching quote
 				[ \t]*				// ignore any spaces/tabs between closing quote and )
 			)?						// title is optional
 			\)
 		)
 		/g,writeAnchorTag);
 	*/
 	text = text.replace(/(\[((?:\[[^\]]*\]|[^\[\]])*)\]\([ \t]*()<?(.*?(?:\(.*?\).*?)?)>?[ \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;
 }
 
 var writeAnchorTag = function(wholeMatch,m1,m2,m3,m4,m5,m6,m7) {
 	if (m7 == undefined) m7 = "";
 	var whole_match = m1;
 	var link_text   = m2;
 	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[link_id] != undefined) {
 			url = g_urls[link_id];
 			if (g_titles[link_id] != undefined) {
 				title = g_titles[link_id];
 			}
 		}
 		else {
 			if (whole_match.search(/\(\s*\)$/m)>-1) {
 				// Special case for explicit empty url
 				url = "";
 			} else {
 				return whole_match;
 			}
 		}
 	}
 
 	url = escapeCharacters(url,"*_");
 	var result = "<a href=\"" + url + "\"";
 
 	if (title != "") {
 		title = title.replace(/"/g,"&quot;");
 		title = escapeCharacters(title,"*_");
 		result +=  " title=\"" + title + "\"";
 	}
 
 	result += ">" + link_text + "</a>";
 
 	return result;
 }
 
 
 var _DoImages = function(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;
 }
 
 var writeImageTag = function(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[link_id] != undefined) {
 			url = g_urls[link_id];
 			if (g_titles[link_id] != undefined) {
 				title = g_titles[link_id];
 			}
 		}
 		else {
 			return whole_match;
 		}
 	}
 
 	alt_text = alt_text.replace(/"/g,"&quot;");
 	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 = title.replace(/"/g,"&quot;");
 		title = escapeCharacters(title,"*_");
 		result +=  " title=\"" + title + "\"";
 	//}
 
 	result += " />";
 
 	return result;
 }
 
 
 var _DoHeaders = function(text) {
 
 	// Setext-style headers:
 	//	Header 1
 	//	========
 	//
 	//	Header 2
 	//	--------
 	//
 	text = text.replace(/^(.+)[ \t]*\n=+[ \t]*\n+/gm,
 		function(wholeMatch,m1){return hashBlock('<h1 id="' + headerId(m1) + '">' + _RunSpanGamut(m1) + "</h1>");});
 
 	text = text.replace(/^(.+)[ \t]*\n-+[ \t]*\n+/gm,
 		function(matchFound,m1){return hashBlock('<h2 id="' + headerId(m1) + '">' + _RunSpanGamut(m1) + "</h2>");});
 
 	// 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 hashBlock("<h" + h_level + ' id="' + headerId(m2) + '">' + _RunSpanGamut(m2) + "</h" + h_level + ">");
 		});
 
 	function headerId(m) {
 		return m.replace(/[^\w]/g, '').toLowerCase();
 	}
 	return text;
 }
 
 // This declaration keeps Dojo compressor from outputting garbage:
 var _ProcessListItems;
 
 var _DoLists = function(text) {
 //
 // 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";
 
 			// Turn double returns into triple returns, so that we can make a
 			// paragraph for the last item in a list, if necessary:
 			list = list.replace(/\n{2,}/g,"\n\n\n");;
 			var result = _ProcessListItems(list);
 
 			// Trim any trailing whitespace, to put the closing `</$list_type>`
 			// up on the preceding line, to get it past the current stupid
 			// HTML block parser. This is a hack to work around the terrible
 			// hack that is the HTML block parser.
 			result = result.replace(/\s+$/,"");
 			result = "<"+list_type+">" + 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";
 			// Turn double returns into triple returns, so that we can make a
 			// paragraph for the last item in a list, if necessary:
 			var list = list.replace(/\n{2,}/g,"\n\n\n");;
 			var result = _ProcessListItems(list);
 			result = runup + "<"+list_type+">\n" + result + "</"+list_type+">\n";
 			return result;
 		});
 	}
 
 	// attacklab: strip sentinel
 	text = text.replace(/~0/,"");
 
 	return text;
 }
 
 _ProcessListItems = function(list_str) {
 //
 //  Process the contents of a single ordered or unordered list, splitting it
 //  into individual list items.
 //
 	// 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";
 
 	/*
 		list_str = list_str.replace(/
 			(\n)?							// leading line = $1
 			(^[ \t]*)						// leading whitespace = $2
 			([*+-]|\d+[.]) [ \t]+			// list marker = $3
 			([^\r]+?						// list item text   = $4
 			(\n{1,2}))
 			(?= \n* (~0 | \2 ([*+-]|\d+[.]) [ \t]+))
 		/gm, function(){...});
 	*/
 	list_str = list_str.replace(/(\n)?(^[ \t]*)([*+-]|\d+[.])[ \t]+([^\r]+?(\n{1,2}))(?=\n*(~0|\2([*+-]|\d+[.])[ \t]+))/gm,
 		function(wholeMatch,m1,m2,m3,m4){
 			var item = m4;
 			var leading_line = m1;
 			var leading_space = m2;
 
 			if (leading_line || (item.search(/\n{2,}/)>-1)) {
 				item = _RunBlockGamut(_Outdent(item));
 			}
 			else {
 				// Recursion for sub-lists:
 				item = _DoLists(_Outdent(item));
 				item = item.replace(/\n$/,""); // chomp(item)
 				item = _RunSpanGamut(item);
 			}
 
 			return  "<li>" + item + "</li>\n";
 		}
 	);
 
 	// attacklab: strip sentinel
 	list_str = list_str.replace(/~0/g,"");
 
 	g_list_level--;
 	return list_str;
 }
 
 
 var _DoCodeBlocks = function(text) {
 //
 //  Process Markdown `<pre><code>` blocks.
 //
 
 	/*
 		text = text.replace(text,
 			/(?:\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|^)((?:(?:[ ]{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 hashBlock(codeblock) + nextChar;
 		}
 	);
 
 	// attacklab: strip sentinel
 	text = text.replace(/~0/,"");
 
 	return text;
 };
 
 var _DoGithubCodeBlocks = function(text) {
 //
 //  Process Github-style code blocks
 //  Example:
 //  ```ruby
 //  def hello_world(x)
 //    puts "Hello, #{x}"
 //  end
 //  ```
 //
 
 
 	// attacklab: sentinel workarounds for lack of \A and \Z, safari\khtml bug
 	text += "~0";
 
 	text = text.replace(/(?:^|\n)```(.*)\n([\s\S]*?)\n```/g,
 		function(wholeMatch,m1,m2) {
 			var language = m1;
 			var codeblock = m2;
 
 			codeblock = _EncodeCode(codeblock);
 			codeblock = _Detab(codeblock);
 			codeblock = codeblock.replace(/^\n+/g,""); // trim leading newlines
 			codeblock = codeblock.replace(/\n+$/g,""); // trim trailing whitespace
 
 			codeblock = "<pre><code" + (language ? " class=\"" + language + '"' : "") + ">" + codeblock + "\n</code></pre>";
 
 			return hashBlock(codeblock);
 		}
 	);
 
 	// attacklab: strip sentinel
 	text = text.replace(/~0/,"");
 
 	return text;
 }
 
 var hashBlock = function(text) {
 	text = text.replace(/(^\n+|\n+$)/g,"");
 	return "\n\n~K" + (g_html_blocks.push(text)-1) + "K\n\n";
 }
 
 var _DoCodeSpans = function(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
 			(`+)						// $2 = Opening run of `
 			(							// $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);
 			return m1+"<code>"+c+"</code>";
 		});
 
 	return text;
 }
 
 var _EncodeCode = function(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;
 }
 
 
 var _DoItalicsAndBold = function(text) {
 
 	// <strong> must go first:
 	text = text.replace(/(\*\*|__)(?=\S)([^\r]*?\S[*_]*)\1/g,
 		"<strong>$2</strong>");
 
 	text = text.replace(/(\*|_)(?=\S)([^\r]*?\S)\1/g,
 		"<em>$2</em>");
 
 	return text;
 }
 
 
 var _DoBlockQuotes = function(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;
 }
 
 
 var _FormParagraphs = function(text) {
 //
 //  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 = [];
 
 	//
 	// 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 (str.search(/~K(\d+)K/g) >= 0) {
 			grafsOut.push(str);
 		}
 		else if (str.search(/\S/) >= 0) {
 			str = _RunSpanGamut(str);
 			str = str.replace(/^([ \t]*)/g,"<p>");
 			str += "</p>"
 			grafsOut.push(str);
 		}
 
 	}
 
 	//
 	// Unhashify HTML blocks
 	//
 	end = grafsOut.length;
 	for (var i=0; i<end; i++) {
 		// if this is a marker for an html block...
 		while (grafsOut[i].search(/~K(\d+)K/) >= 0) {
 			var blockText = g_html_blocks[RegExp.$1];
 			blockText = blockText.replace(/\$/g,"$$$$"); // Escape any dollar signs
 			grafsOut[i] = grafsOut[i].replace(/~K\d+K/,blockText);
 		}
 	}
 
 	return grafsOut.join("\n\n");
 }
 
 
 var _EncodeAmpsAndAngles = function(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\/?\$!])/gi,"&lt;");
 
 	return text;
 }
 
 
 var _EncodeBackslashEscapes = function(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 _DoAutoLinks = function(text) {
 
 	text = text.replace(/<((https?|ftp|dict):[^'">\s]+)>/gi,"<a href=\"$1\">$1</a>");
 
 	// Email addresses: <address@domain.foo>
 
 	/*
 		text = text.replace(/
 			<
 			(?:mailto:)?
 			(
 				[-.\w]+
 				\@
 				[-a-z0-9]+(\.[-a-z0-9]+)*\.[a-z]+
 			)
 			>
 		/gi, _DoAutoLinks_callback());
 	*/
 	text = text.replace(/<(?:mailto:)?([-.\w]+\@[-a-z0-9]+(\.[-a-z0-9]+)*\.[a-z]+)>/gi,
 		function(wholeMatch,m1) {
 			return _EncodeEmailAddress( _UnescapeSpecialChars(m1) );
 		}
 	);
 
 	return text;
 }
 
 
 var _EncodeEmailAddress = function(addr) {
 //
 //  Input: an email address, e.g. "foo@example.com"
 //
 //  Output: the email address as a mailto link, with each character
 //	of the address encoded as either a decimal or hex entity, in
 //	the hopes of foiling most address harvesting spam bots. E.g.:
 //
 //	<a href="&#x6D;&#97;&#105;&#108;&#x74;&#111;:&#102;&#111;&#111;&#64;&#101;
 //	   x&#x61;&#109;&#x70;&#108;&#x65;&#x2E;&#99;&#111;&#109;">&#102;&#111;&#111;
 //	   &#64;&#101;x&#x61;&#109;&#x70;&#108;&#x65;&#x2E;&#99;&#111;&#109;</a>
 //
 //  Based on a filter by Matthew Wickline, posted to the BBEdit-Talk
 //  mailing list: <http://tinyurl.com/yu7ue>
 //
 
 	var encode = [
 		function(ch){return "&#"+ch.charCodeAt(0)+";";},
 		function(ch){return "&#x"+ch.charCodeAt(0).toString(16)+";";},
 		function(ch){return ch;}
 	];
 
 	addr = "mailto:" + addr;
 
 	addr = addr.replace(/./g, function(ch) {
 		if (ch == "@") {
 		   	// this *must* be encoded. I insist.
 			ch = encode[Math.floor(Math.random()*2)](ch);
 		} else if (ch !=":") {
 			// leave ':' alone (to spot mailto: later)
 			var r = Math.random();
 			// roughly 10% raw, 45% hex, 45% dec
 			ch =  (
 					r > .9  ?	encode[2](ch)   :
 					r > .45 ?	encode[1](ch)   :
 								encode[0](ch)
 				);
 		}
 		return ch;
 	});
 
 	addr = "<a href=\"" + addr + "\">" + addr + "</a>";
 	addr = addr.replace(/">.+:/g,"\">"); // strip the mailto: from the visible part
 
 	return addr;
 }
 
 
 var _UnescapeSpecialChars = function(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;
 }
 
 
 var _Outdent = function(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;
 }
 
 var _Detab = function(text) {
 // attacklab: Detab's completely rewritten for speed.
 // In perl we could fix it by anchoring the regexp with \G.
 // In javascript we're less fortunate.
 
 	// expand first n-1 tabs
 	text = text.replace(/\t(?=\t)/g,"    "); // attacklab: g_tab_width
 
 	// replace the nth with two sentinels
 	text = text.replace(/\t/g,"~A~B");
 
 	// use the sentinel to anchor our regex so it doesn't explode
 	text = text.replace(/~B(.+?)~A/g,
 		function(wholeMatch,m1,m2) {
 			var leadingText = m1;
 			var numSpaces = 4 - leadingText.length % 4;  // attacklab: g_tab_width
 
 			// there *must* be a better way to do this:
 			for (var i=0; i<numSpaces; i++) leadingText+=" ";
 
 			return leadingText;
 		}
 	);
 
 	// clean up sentinels
 	text = text.replace(/~A/g,"    ");  // attacklab: g_tab_width
 	text = text.replace(/~B/g,"");
 
 	return text;
 }
 
 
 //
 //  attacklab: Utility functions
 //
 
 
 var escapeCharacters = function(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;
 }
 
 
 var escapeCharacters_callback = function(wholeMatch,m1) {
 	var charCodeToEscape = m1.charCodeAt(0);
 	return "~E"+charCodeToEscape+"E";
 }
 
 } // end of Showdown.converter
 
 
 // export
 if (typeof module !== 'undefined') module.exports = Showdown;
 
 // stolen from AMD branch of underscore
 // AMD define happens at the end for compatibility with AMD loaders
 // that don't enforce next-turn semantics on modules.
 if (typeof define === 'function' && define.amd) {
     define('showdown', function() {
         return Showdown;
     });
 }