[Boost-users] [statechart] Unhandled events

Subject: [Boost-users] [statechart] Unhandled events
From: Oleg Smolsky (oleg_at_[hidden])
Date: 2010-10-07 03:25:30

  Hey there, I've been using SC for a while and something has been 
bugging me - given a state machine with:
     OuterSt, OneSt and TwoSt

as well as OneEv and TwoEv that are handled by OneSt and TwoSt 
respectively, it is possible to send a wrong event to either of the last 
two states. Such an "unhandled" event will be forwarded to OuterSt and 
then quietly eaten.

My question is as follows - is it possible to define some kind of "catch 
all" handler in the OuterSt? I have already fixed a tricky bug in my 
code where a submitted event was lost, and wonder if there is a simple 
way to handle these situations? I can certainly add a 
custom_reaction<>(X) for each possible event to the OuterSt and catch 
issues that way, but that's far from ideal.

Any suggestions would be appreciated.

P.S. perhaps a compromise solution would be to add something like this 
to OuterSt:
     sc::bug<OneEv>
     sc::bug<TwoEv>

but that would effectively limit handling to issuing an assert(false)...

Thanks,
Oleg.