pegdown is nearly 100% compatible with the original Markdown specification and fully passes the original Markdown test suite. On top of the standard Markdown feature set pegdown implements a number of extensions similar to what other popular Markdown processors offer. Currently pegdown supports the following extensions over standard Markdown:
- SMARTS: Beautifys apostrophes, dashes and ellipsises.
- QUOTES: Beautifys single and double quotes.
- SMARTYPANTS: Convenience extensions enabling both, SMARTS and QUOTES, at once.
- ABBREVIATIONS: Support for abbreviations in the way of PHP Markdown Extra.
- HARDWRAPS: Enables alternative handling of newlines, see [Github-flavoured-Markdown]
- AUTOLINKS: Enables plain (undelimited) autolinks the way [Github-flavoured-Markdown] implements them.
More extensions like support for tables, etc. are planned.
Note: pegdown differs from the original Markdown in that it ignores in-word emphasis as in
> my_file.txt > 2*3*4=5
Currently this "extension" cannot be switched off.
Using pegdown is very simple: Just create a new instance of a PegDownProcessor and call its markdownToHtml(String) method to convert the given Markdown source to an HTML string.
The first time you create a PegDownProcessor it can take up to a few hundred milliseconds to prepare the underlying parboiled parser instance, however, once the first processor has been built all further instantiations will be fast. Also, you can reuse an existing PegDownProcessor instance as often as you want, as long as you prevent concurrent accesses, since neither the PegDownProcessor nor the underlying parser is thread-safe.
See http://sirthias.github.com/pegdown/api for the pegdown API documation.
Most of the underlying PEG grammar was developed by John MacFarlane and made available with his tool peg-markdown.
Any feedback is, of course, very welcome.