Rebuttal to Ariane paper

[Ken Garlington <kennieg@flash.net>]

Jean-Marc Jezequel wrote:
> 
> I've put on a page with a few Usenet comments about the paper, including a
> link to your paper. Please check it at:
> 
> http://www.irisa.fr/pampa/EPEE/Ariane5-comments.html

I'll add a link to this in my paper this weekend. Some notes:

- I've changed my address from kennieg@flash.net to
Ken.Garlington@computer.org.
It would help if you could make this change in your paper as well.

- In your critique, you state: "Stricly speaking, it is very clear that
DBC by
itself is neither sufficient (it needs to be integrated in a proper
system
and software engineering process) nor necessary...", where the "system
and
software engineering process" references your book. I could find no
reference
to your book in the Ariane paper, or to a system and software
engineering
process beyond DBC/Eiffel. It appears that you are agreeing with my
critique
of the _paper_ (as opposed to your _personal_ position, as described in
your
rebuttal).

- Looking at the table of contents of your book, only chapters 6 and 7
appear
to address a system and software engineering process. In particular, for
systems analysis, an "object oriented analysis" is defined. Is Eiffel
used
to describe this analysis (presumably done as part of OMT)? If not, then
what approach/notation is recommended, and where is this discussed in
the
Ariane paper?

- You also state: "In his critique, Ken seems to overlook the fact that
whereas assertions related to DBC are physically located inside the
code,
they logically belong to the specification of components. Tools are
available to extract this specification. When you want to reuse a
component
(let's say the perfectly valid Ariane4 SRI) in a new system
(let's say Ariane5) the engineer working in a DBC context would check 
with all possible means) whether the new system is happy with the
component
contract." This position is not "overlooked"; it is the entire basis of
section 3.1 of my paper! To date, no one has indicated any specific
flaws
with the argument in this section, so far as I can recall.

- I am also concerned that you quote Eiffel advocates without also
describing
my posted rebuttals to their arguments. In particular, the Ted Velikoff
post
is very misleading, as it addresses an issue that was not the topic of
discussion
at the time. The original post, to which I responded, said that Eiffel
assertions
were superior even if they were _never_ executed (either during test or
production use). Mr. Velikoff did not see this original post, and
assumed a
different topic of conversation.

- You also quote Robert S. White in this paper. I think his comments
reflect
those of Dr. Dewar, but as stated, they appear to support Eiffel/DBC
instead.
I will let Mr. White make any appropriate responses.

- I should also note that I find the Meyer response particularly
offensive, since
it attacks the motives of his critics, denigrates the skills and
knowledge
of aerospace professions that don't use Eiffel, and does not respond to
the
substance of the arguments (except to re-state his position once again).
However,
he has the right to be offensive, and so I'm not suggesting that the
quote be
changed or retracted. In fact, it contradicts your own personal
position: Note
the statement "The pitch, if any, is for the method of Design by
Contract..."
which once again reinforces my claim that the _paper_ is focused on
DBC/Eiffel,
not on a "system and software engineering process."

- Finally, is there any way your link could be posted on www.eiffel.com?
Your
server doesn't appear to be referenced from there, and so readers of the
Ariane
paper have no real way to find this supplemental information.

> --
> Jean-Marc Jezequel               Tel : +33 299 847 192
> IRISA/CNRS                       Fax : +33 299 847 171
> Campus de Beaulieu               e-mail : jezequel@irisa.fr
> F-35042 RENNES (FRANCE)          http://www.irisa.fr/pampa/PROF/jmj.html