The way that I'd achieve the same thing, and be slightly cleaner would be something like this:
class jon-desktop { $packages_to_install_by_default = [ 'icedove', 'git-core', 'vim-gnome', 'vinagre', 'build-essential', 'devscripts', 'subversion', 'git-buildpackage', 'mutt', 'offlineimap', 'ascii', 'gitk', 'chromium-browser', ] package { $packages_to_install_by_default: ensure => installed, } }
This way your actual package resource definition never needs to change. The variable you choose to use to define the list of packages to install can be abstracted away as much as desired.