Ola's Clever Hpricot Hack

If you’re running JRuby from trunk, try this:

 $ gem install hpricot --source http://code.whytheluckystiff.net 
 Select which gem to install for your platform (java) 
 1. hpricot 0.5.110 (jruby) 
 2. hpricot 0.5.110 (mswin32) 
 3. hpricot 0.5.110 (ruby) 
 > 1 
 Successfully installed hpricot-0.5.110-jruby 
 Installing ri documentation for hpricot-0.5.110-jruby... 
 Installing RDoc documentation for hpricot-0.5.110-jruby...

But how is this possible given that Hpricot’s parser is written in C?? Because Ragel can generate Java code! Ola goes into it.