Slides 10-14 (these are really slides 1-5 of the original talk but
the slides are in reversed order) about the Esterel programming language in
"Mixing Dataflow with Control",
by Dr. Wan-Teh Chang (Netscape),
esp. the comparison between textual and graphical specifications of FSMs,
In Esterel example of the FSM, hierarchy interrupts the behavior
via the reset signal (R).
No matter what state you're in, you go back to original state
when receiving R.
In Esterel, interrupt is implemented as do watching statement.