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Subject: Re: [boost] [msm] history pseudo states
From: Michael Caisse (boost_at_[hidden])
Date: 2009-12-07 12:40:58

Christophe Henry wrote:


> I find the concept in UML highly dissatisfying. It simply doesn't fit
> well with orthogonal regions. What if I want to "remember" more than
> one region? With UML, you're out of luck: one history per composite,
> one transition originating from it. Want more? Sorry we can't help
> you.

I apologize. I'm still not clear on the distaste. Ignoring regions
for a minute.... does it make sense then? A composite state could
only have a single history. And the history's transition is the default
if the composite state hasn't been visited yet... so it makes sense
that there could only be one of those too.

Adding in regions messes the whole thing up. And here might be
the sticking point. I can tell you that the history of "return to history"
was from an era without regions. In that context it is a very power

Thank you for taking the time to submit this library.


Michael Caisse
Object Modeling Designs

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