Boost logo

Boost :

Subject: Re: [boost] [msm] eUML guard/action location
From: Michael Caisse (boost_at_[hidden])
Date: 2009-12-07 20:13:26

Christophe Henry wrote:
> Hi Michael,
>> Ok... I looked up MSM's anonymous transitions again and
>> now I don't like it (o;
> It's probably because we don't talk about the same concept. And it's
> not an MSM concept. Sorry, I can't claim ownership for it ;-)
> Anonymous transitions are also called completion events in the
> standard (and both names are used in the excellent "Real-Time UML, 3rd
> Edition").

Thank you for setting me straight on this. It should have dawned
on me that they were completion transitions as described in 15.3.14.
I have a love/hate feeling about them... I don't personally like
the concept of leaving a state via implicit trigger. It just makes
me feel uncomfortable. However, I also see the power they can
afford and use them for exactly your example... stepping along


> What you are talking about is a trigger, which has to be fired,
> whatever it is. I didn't find it in the standard, but I could have
> missed that too. And no, MSM doesn't support it for the moment. The
> reason is that it's not on my radar as I'm pretty unconvinced of its
> need. I have yet to see a good convincing use case for it. Now, I
> don't say it won't be done, but it's not high on my list, unless
> someone makes a convincing case for it. Its implementation might be
> not trivial though.

Yes, it is the trigger. Sorry I got sloppy with the terminology.
I hope to start sending some example machines and my perceptions
later tonight. They will have several use-cases of these types of

Right now I'm pushing on the edges of what I'm learning from the docs
and a little bit of playing so I can determine how to convert basic
constructs I use a lot from the model to the implementation. Thanks
for putting up with me.


Michael Caisse
Object Modeling Designs

Boost list run by bdawes at, gregod at, cpdaniel at, john at