1. Introduction to
league/commonmark
Colin O’Dell

2. Colin O’Dell
Lead Web Developer at Unleashed Technologies
PHP developer since 2002
Author of:
• league/commonmark
• league/html-to-markdown
• PHP 7 Migration Guide e-book
@colinodell
www.colinodell.com

3. league/commonmark
A well-written, super-configurable Markdown
parser for PHP based on the CommonMark spec.

4. CommonMark is…
A strongly defined, highly compatible specification of Markdown.
Written by people from Github, StackOverflow, Reddit, and others.
Spec includes:
• Strict rules (precedence, parsing order, handling edge cases)
• Specific definitions (ex: “whitespace”, “punctuation”)
• 613 examples

5. Why is it needed?
*I love Markdown*
<p><em>I love Markdown</em></p>

6. Why is it needed?
*I *love* Markdown*
Source: http://johnmacfarlane.net/babelmark2/

7. 30%
Why is it needed?
*I *love* Markdown*
<p><em>I <em>love</em> Markdown</em></p>
*I *love* Markdown*
<p><em>I </em>love<em> Markdown</em></p>
*I *love* Markdown*
<p><em>I *love</em> Markdown*</p>
15%
33%
Source: http://johnmacfarlane.net/babelmark2/

8. league/commonmark
A well-written, super-configurable Markdown
parser for PHP based on the CommonMark spec.
1. Supports the full CommonMark standard

9. league/commonmark
A well-written, super-configurable Markdown
parser for PHP based on the CommonMark spec.
1. Supports the full CommonMark standard
2. Easy to implement

10. Adding league/commonmark
$ composer require league/commonmark:^0.13
<?php
$converter = new CommonMarkConverter();
echo $converter->convertToHtml('Hello **Nomad PHP!**');

11. Integrations

12. league/commonmark
A well-written, super-configurable Markdown
parser for PHP based on the CommonMark spec.
1. Supports the full CommonMark standard
2. Easy to implement

13. league/commonmark
A well-written, super-configurable Markdown
parser for PHP based on the CommonMark spec.
1. Supports the full CommonMark standard
2. Easy to implement
3. Easy to customize

14. Customization Example
<https://www.nomadphp.com>
<a href="https://www.nomadphp.com">
https://www.nomadphp.com
</a>

15. Conversion Process
<https://www.nomadphp.com>
Markdown Parse

16. <document>
<paragraph>
<link destination="https://www.nomadphp.com">
<text>https://www.nomadphp.com</text>
</link>
</paragraph>
</document>
Conversion Process
Markdown ASTParse RenderParse

17. Conversion Process
<a href="https://www.nomadphp.com">
https://www.nomadphp.com
</a>
Markdown AST HTMLParse RenderParse

18. Conversion Process
Markdown AST HTMLParse RenderParse
Add your own custom parser, processor, or renderer

19. Customization Example
<https://www.nomadphp.com>
<a href="https://www.nomadphp.com">
https://www.nomadphp.com
</a>
<@nomadphp>
<a href="https://twitter.com/nomadphp">
@nomadphp
</a>

20. Customizing league/commonmark
class TwitterUsernameAutolinkParser extends AbstractInlineParser {
public function getCharacters() {
return ['<'];
}
public function parse(InlineParserContext $inlineContext) {
$cursor = $inlineContext->getCursor();
if ($match = $cursor->match('/^<@[A-Za-z0-9_]+>/')) {
// Remove the starting '<@' and ending '>' that were matched
$username = substr($match, 2, -1);
$profileUrl = 'https://twitter.com/' . $username;
$link = new Link($profileUrl, '@'.$username);
$inlineContext->getContainer()->appendChild($link);
return true;
}
return false;
}
}

21. league/commonmark
A well-written, super-configurable Markdown
parser for PHP based on the CommonMark spec.
1. Supports the full CommonMark standard
2. Easy to implement
3. Easy to customize

22. league/commonmark
A well-written, super-configurable Markdown
parser for PHP based on the CommonMark spec.
1. Supports the full CommonMark standard
2. Easy to implement
3. Easy to customize
4. Full UTF-8 compatibility

23. league/commonmark
A well-written, super-configurable Markdown
parser for PHP based on the CommonMark spec.
1. Supports the full CommonMark standard
2. Easy to implement
3. Easy to customize
4. Full UTF-8 compatibility
5. Well-tested

24. Installation & Documentation:
http://github.com/thephpleague/commonmark
Learn More About CommonMark:
http://commonmark.org
Slides / Feedback:
http://joind.in/16748 @colinodell