This seems reminiscent of Session Types to me: https://en.wikipedia.org/wiki/Session_type https://en.wikipedia.org/wiki/Session_type I think one difference is

This seems reminiscent of Session Types to me: https://en.wikipedia.org/wiki/Session_type https://en.wikipedia.org/wiki/Session_type I think one difference is that session types capture which state a process/co-routine is in after receiving a sequence of messages whereas this system does not, it captures how one can respond to each state in isolation (e.g. I don't think you can statically capture that once a door is closed and locked you can only receive the locked state from it and respond by unlocking it).