Re: Comparison : Ada and UML (comparison… indeed)

["Vinzent Hoefler" <nntp-2010-10@t-domaingrabbing.de>]

On Sun, 31 Oct 2010 11:18:05 +0100, Yannick Duchêne (Hibou57) <yannick_duchene@yahoo.fr> wrote:

> Le Sun, 31 Oct 2010 09:33:15 +0100, Vinzent Hoefler
> <nntp-2010-10@t-domaingrabbing.de> a écrit:
>> HOOD emphasizes the use of state transition diagrams, data flow diagrams,
>> and context diagrams.
> That's nice, there is no Data-Flow diagram in UML. But Scenario seems
> required, and you did not mentioned it.

I would probably express them with context diagrams.

Apart from that HOOD is very text-oriented.
You just say what you need to say. ;)

>> I think that's the wrong way of looking at HOOD.
>>
>> HOOD still is a design _method_ applying certain rules and restrictions.
>> It just uses a specific notation (merely for historical reasons, I'd
>> say).
>>
>> UML on the other hand is a meta-language, so nobody stops you from
>> expressing a HOOD design in UML notation with the appropriate
>> stereotypes.
>
> I see both point, and here is : what is involved is not only notation,
> also semantic.

Yes. I would even say, the semantic is all that matters. Notation is just
an agreement, so that everybody else understands the same semantic.

> picture). Then about using stereotypes, this is something I would like to
> avoid, precisely for semantic matters, as it seems many people already
> draw diagrams without exact semantic in mind (an example, would be to Draw
> a package, and give that package the Ada semantic instead of the UML
> semantic). No need to add more possible source of miss-understanding.

Well, when I said "appropriate stereotypes" this was meant to be "stereotypes
with the properly defined semantic". Agreement about it (see above) plays the
most important part here.

Just drawing pictures where everybody else understands something different,
doesn't help, of course. But mis-using UML like you describe above seems a
common way of doing design these days. ;)

> For the smalltalk, all the above is also why I consider popularity. I
> simply expect “more popular = more understood”.

Well, yes. The other possibility could be to restrict the possible
notation to a very small set so that even a novice can understand the
semantic in a couple of days.

One is UML which is popular, so it is supposed to be understood, but has a
very large set of notations which are not even easy to grasp (at least not
in a couple of days), the other one is HOOD which is not popular, but the
set of symbols is rather small, so it's relatively easy to learn.

So, if you restrict the UML notation to the HOOD subset, you can get both. ;)


Vinzent.

-- 
There is no signature.