"This document describes a Tcl package named, rosea. Rosea is an execution architecture intended as the target for translating XUML models using Tcl as the implementation language. The package consists of a run time execution library that implements the XUML semantics and a domain specific configuration language that is used to specify the XUML domain model and generate the required data for the run time execution. Rosea uses TclRAL as the basis of its data architecture and that enables referential integrity constraint checking based on the XUML class diagram relationships and supports set-at-a-time operations on domain class instances. Processing is transactional and constraint violations result in rolling back the changes to a known good state."
I find this program very interesting because it is used, among other things, for medical device embedded software; ie, perhaps the most challenging high stakes programming environment. The author makes maximum achievable software quality an explicit goal.
The originally linked command reference is a little short on "what" and "why".