Markdown Extended

An extended PHP version of Markdown syntax parser

PHP Markdown Extended is a PHP package to transform Markdown text files or strings in HTML. This new version of a Markdown parser tries to propose a complete set of Markdown syntax tags and rules and to be PHP-5.3+ compliant.

Markdown Mark

What is Markdown?

Created by John Gruber in 2004, Markdown is, as he says:

a text-to-HTML conversion tool for web writers. Markdown allows you to write using an easy-to-read, easy-to-write plain text format, then convert it to structurally valid XHTML (or HTML).

As I would say, Markdown is a set of writing rules to build some human readable text contents, such as .txt common files, which can be parsed to build some HTML valid content, structurally and typographically.

This syntax has become one of the most common standards of rich-text contents, used for instance by GitHub as one of the proposed syntaxes for informational files (such like this one).

A short history of Markdown

The first idea was from John Gruber, coded in {Perl} script.

An extended implementation, known as Markdown Extra, has been written by Michel Fortin, coded in {PHP} script.

Another extended implementation, known as Multi Markdown, has been written by Fletcher T. Penney, coded in {Perl} script.

So why a new version of Markdown?

  • This version, known as PHP Markdown Extended, tries to collect the different rules and tags used by the three versions listed above.
  • It is a PHP script that can be used in any PHP project.
  • It is coded following the PHP 5.3 coding standards and is Composer compliant.
  • It can be used in command line interface, with a full set of options.
  • It can be configured for specific needs.
  • It is built to construct complex parsing by creating some single-key-unit objects for all important Markdown stuff (content, configuration, parser, template and rules).


As for all our packages, we try to follow the coding standards and naming rules most commonly in use:

Knowing that, all classes are named and organized in an architecture to allow the use of the standard SplClassLoader.

The whole package is embedded in the MarkdownExtended namespace.


You can use this package in your work in many ways.

First, you can clone the GitHub repository and include it “as is” in your poject:

~$ wget --no-check-certificate

You can also download an archive from Github.

Then, to use the package classes, you just need to register the MarkdownExtended namespace directory using the SplClassLoader or any other custom autoloader (if required, a copy is proposed in the package):

require_once 'path/to/package/src/SplClassLoader.php';
$classLoader = new SplClassLoader('MarkdownExtended', '/path/to/package/src');

Another way to use the package, if you are a Composer user, is to add it to your requirements in your composer.json:

"require": {
    "picas/markdown-extended": "dev-master"

The namespace will be automatically added to the project’s Composer autoloader.


PHP script usage

The MarkdownExtended package can be simply call writing:

// creation of the singleton instance of \MarkdownExtended\MarkdownExtended
$content = \MarkdownExtended\MarkdownExtended::create()
    // get the \MarkdownExtended\Parser object passing it some options (optional)
    ->get('Parser', $options)
    // launch the transformation of a source content
    ->parse( new \MarkdownExtended\Content($source) )
    // get the result content object

This will load in $content the parsed HTML version of your original Markdown $source. To get the part you need from the content:

echo $content->getBody();

For simplest usage, some aliases are designed in the MarkdownExtended kernel:

// to parse a string content:
\MarkdownExtended\MarkdownExtended::transformString($source [, $parser_options]);

// to parse a file content:
\MarkdownExtended\MarkdownExtended::transformSource($filename [, $parser_options]);

These two methods returns a \MarkdownExtended\Content object. To finally get an HTML version, write:

\MarkdownExtended\MarkdownExtended::transformString($source [, $parser_options]);
echo \MarkdownExtended\MarkdownExtended::getFullContent();

Old parsers compatibility

To keep the package compatible with old versions of Markdown, an interface is embedded with the common Markdown($content) function ; to use it, just include the file src/markdown.php:

require_once 'path/to/src/markdown.php';

// to get result of a string parsing:
echo Markdown($string [, $options]);

// to get result of a file content parsing:
echo MarkdownFromSource($file_name [, $options]);

Command line usage

A short command line interface is proposed in the package running:

~$ bin/markdown-extended --help

This interface allows you to parse one or more files, extract some informations from sources, write the results in files and some other stuff.

To generate a man-page from file docs/ with the interface itself, run:

~$ bin/markdown-extended -f man -o bin/ docs/
~$ man ./bin/

Apache handler usage

A sample of direct Apache handler is designed in the demo/cgi-scripts/ directory of the package. It allows you to automatically transform Markdown content files in HTML thru a browser classic navigation. To learn more about this feature, please see the dedicated How-To.

Open-Source & Community

This plugin is a free software, available under BSD license ; you can freely use it, for yourself or a commercial use, modify its source code according to your needs, freely distribute your work and propose it to the community, as long as you let an information about its first authors.

As the sources are hosted on a GIT repository on GitHub, you can modify it, to ameliorate a feature or correct an error, by creating your own fork of this repository, modifying it and asking to pull your modifications on the original branch.

Please note that the “master” branch is always the latest stable version of the code. Development is done on branch “wip” and you can create a new one for your own developments. A developer help and roadmap is provided in the docs. The latest version of the package documentation is available online at

Note that the package is integrated with Travis CI.


This software, as the original Markdown, is licensed under the terms of the BSD-3-Clause open source license.

You can use, transform and distribute this software and its dependencies as you wish, as long as you mention the copyrights below:

Copyright © 2004-2006, John Gruber
All rights reserved.

Copyright © 2005-2009 Fletcher T. Penney
All rights reserved.

PHP Markdown & Extra
Copyright © 2004-2012 Michel Fortin
All rights reserved.

Markdown Extended
Copyright © 2008-2013 Pierre Cassat & contributors
All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are
permitted provided that the following conditions are met:

- Redistributions of source code must retain the above copyright notice, this list of
  conditions and the following disclaimer.

- Redistributions in binary form must reproduce the above copyright notice, this list
  of conditions and the following disclaimer in the documentation and/or other materials
  provided with the distribution.

- Neither the name “Markdown” nor the names of its contributors may be used to endorse
  or promote products derived from this software without specific prior written permission.

This software is provided by the copyright holders and contributors “as is” and any
express or implied warranties, including, but not limited to, the implied warranties
of merchantability and fitness for a particular purpose are disclaimed. In no event
shall the copyright owner or contributors be liable for any direct, indirect,
incidental, special, exemplary, or consequential damages (including, but not limited
to, procurement of substitute goods or services; loss of use, data, or profits; or
business interruption) however caused and on any theory of liability, whether in
contract, strict liability, or tort (including negligence or otherwise) arising in
any way out of the use of this software, even if advised of the possibility of such