The puppet editor tips page seems to suggest that using eclipse & dltk (presumably the ruby tools) will assist with editing .pp files.
http://projects.puppetlabs.com/projects/1/wiki/Editor_Tips
I can't see any difference or get syntax highlighting with DLTK 1.0 and the ruby plugins installed. Is there something I'm missing or eclipse configuration I need to set for it to start doing syntax highlighting and validation of my puppet model?
Before the above will work, I had to create a new eclipse ruby project and add a ruby interpreter pointing at /usr/bin/ruby (the default install location of ruby on Mac OS X).
After that was done, it was possible to open and highlight .pp files in the Ruby editor and get syntax highlighting working.
It also helps to link the .pp file type with the ruby editor in the General > Editors > File Associations section of the Eclipse preferences.
Also checkout the project https://github.com/cloudsmith/geppetto which contains a Puppet .pp parser/editor with syntax coloring, error markers, etc. and with features that makes it easy to work with puppet modules.
Geppetto is available as a ready to use download, or as features installable into Eclipse.