Are you trying to update an old formatter to the newest release? The old
formatter API has changed in the latest release.
At the moment the best place to look is the current formatters source
pretty_formatter.rb is a good start.
Another good place to look would be the visitor class that contains all
the formatter hooks.
Note the current page on the wiki about formatters
applies to latest stable release (0.1.16). Once we have stablised the
Formatter api for version 0.2 we can update this page with the new