I am aware of following projects (mostly from http://www.w3.org/community/markdown/wiki/MarkdownImplementations):
implemented in Java:
- txtmark http://github.com/rjeschke/txtmark (claims to be fastest MD processor running on the JVM)
- Markdown4j http://code.google.com/p/markdown4j (fork of txtmark, advantages? more active dev?)
- MarkdownPapers http://markdown.tautua.org/ (based on JavaCC parser)
- pegdown http://github.com/sirthias/pegdown
- MarkdownJ http://code.google.com/p/markdownj (abandoned?)
implemented in Scala:
- Laika https://github.com/planet42
- Actuarius http://henkelmann.eu/projects/actuarius/ (acc. to author not fully standards compliant)
- Knockoff http://tristanhunt.com/projects/knockoff (only subset of MD?)
- ScalaMD https://github.com/chirino/scalamd
Q: What are the respective performance characteristics, pitfalls, quirks? Which ones support the Github extensions? Which one would you recommend for a Play! / Scala application?
