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From: Scott Woods (scottw_at_[hidden])
Date: 2002-09-09 16:32:36

> class Open;
> class Locked : public boost::fsm::state< Locked, Lock >,
> public boost::fsm::transition< Locked, Lock::EvUnlock, Open
> {
> public:
> Locked( context_ptr_type pContext ) : base_type( pContext ) {}
> };
> class Open : public boost::fsm::state< Open, Lock >,
> public boost::fsm::transition< Open, Lock::EvLock, Locked
> {
> public:
> Open( context_ptr_type pContext ) : base_type( pContext ) {}
> };

I understand (mostly) what is involved here but still struggle with the
sheer quantity
of framing/cruft/... required to implement a machine. I have followed the
so far and realise there is a real history to this. GOF and UML are good
references to wave around when presenting new work. GOF is a pretty abstract
reference (rightly so ;-) while UML (FSM) is a formal language (?) for
state machines. My question - is there no potential to "de-normalize" from
ideals, with the goal of making it easier for the developer? I have had some
to FSMs (with SDL) and feel more prepared to tackle a FSM library than
might be. So if I find it hard then how is it going to be for someone on
their first
time up? OTOH we (developers) always want everything to fit in 3 lines ;-).

Wondered about the commitment to UML FSMs but I suppose that SDL cant
really compete, in terms of who-is-using-what modelling techniques.

The type of FSMs that I have been dealing with can be characterized as; a
dynamic community of co-operating FSMs distributed over a network of
devices. That's pretty "waffley" but hopefull captures the essence of it. My
dilemma with your FSM library is that I don't think it has these kind of
goals (no
library seems to BTW ;-) and its also quite difficult to divide the signal
(i.e. FSM events) from the distributed nature of my problem space (e.g.
transports and messaging systems).

Any thoughts in those areas?


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