In ruby we have the very mature and featureful state_machine gem: https://github.com/pluginaweek/state_machine https://github.com/pluginaweek/state_machine I

In ruby we have the very mature and featureful state_machine gem: https://github.com/pluginaweek/state_machine https://github.com/pluginaweek/state_machine I recently found out you can even choose to define states using arbitrary objects/functions, eg. date ranges. Sounds a bit crazy but I can see it solving certain problems very neatly.