showdown.js

//
// 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 "$text" with "text".  Be sure to ignore whitespace
// and line endings.
//
//
// Showdown usage:
//
//   var text = "Markdown *rocks*.";
//
//   var converter = new Showdown.converter();
//   var html = converter.makeHtml(text);
//
//   alert(html);
//
// Note: move the sample code to the bottom of this
// file before uncommenting it.
//
//
// Showdown namespace
//
var Showdown={extensions:{}},forEach=Showdown.forEach=function(a,b){if(typeof a.forEach=="function")a.forEach(b);else{var c,d=a.length;for(c=0;c<d;c++)b(a[c],c,a)}},stdExtName=function(a){return a.replace(/[_-]||\s/g,"").toLowerCase()};Showdown.converter=function(a){var b,c,d,e=0,f=[],g=[];if(typeof module!="undefind"&&typeof exports!="undefined"&&typeof require!="undefind"){var h=require("fs");if(h){var i=h.readdirSync((__dirname||".")+"/extensions").filter(function(a){return~a.indexOf(".js")}).map(function(a){return a.replace(/\.js$/,"")});Showdown.forEach(i,function(a){var b=stdExtName(a);Showdown.extensions[b]=require("./extensions/"+a)})}}this.makeHtml=function(a){return b={},c={},d=[],a=a.replace(/~/g,"~T"),a=a.replace(/\$/g,"~D"),a=a.replace(/\r\n/g,"\n"),a=a.replace(/\r/g,"\n"),a="\n\n"+a+"\n\n",a=M(a),a=a.replace(/^[ \t]+$/mg,""),Showdown.forEach(f,function(b){a=k(b,a)}),a=z(a),a=m(a),a=l(a),a=o(a),a=K(a),a=a.replace(/~D/g,"$$"),a=a.replace(/~T/g,"~"),Showdown.forEach(g,function(b){a=k(b,a)}),a};if(a&&a.extensions){var j=this;Showdown.forEach(a.extensions,function(a){typeof a=="string"&&(a=Showdown.extensions[stdExtName(a)]);if(typeof a!="function")throw"Extension '"+a+"' could not be loaded.  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