There was a now-defunct python-like language built on .Net called Cobra that had class invariants and other contract functionality. It generally speaking had a

There was a now-defunct python-like language built on .Net called Cobra that had class invariants and other contract functionality. It generally speaking had a lot of ideas focused on high quality programming built into the language which made it great to program against. I wish it had caught on.... http://cobra-language.com/ http://cobra-language.com/