Re: Is DoD simulation ignoring using Ada?????

[emery@goldfinger.mitre.org (David Emery)]

>Developing Ada bindings isn't rocket science; it's well within the
>capabilities of somebody with a year or two of Ada experience.

Oh, I beg to differ.  There's an art to doing bindings.  I've seen
(been victimized) by Ada bindings developed by junior people.  Right
now I'm trying to rework some bindings that fit that pattern.  The guy
did a nice job given his level of experience, but there are some
serious problems that affect both usage and implementation.

Part of the problem is developing/defining the binding so that it is
not tightly coupled to the specific execution environment/compiler.
It's easy to crank out a couple of 'pragma interface (C)', but very
painful to move such a binding to another compiler.  Another issue is
preventing storage leaks.  Of course, if the underlying C interface is
lousy, there's a limit to how well the Ada binding can hide warts and
flaws in the C interface.

The 'art' comes in knowing what/how/when/why to encapsulate.  After
all, Ada bindings should NOT resembe C header files (if they do,
there's no reason to do Ada.), and the art is in figuring out the best
way to identify and represent the underlying abstractions in Ada.  My
10 years of experience doing Ada bindings says that experience has
been the best teacher in this regard.  (How's that for
self-referential...)

But, with the right skills and expeience, a good engineer can crank
out a high-quality Ada binding in a (relatively) short amount of time.
And my experience has been that the cost of doing a high-quality Ada
binding is very quickly recovered by savings in debug time, etc.  Part
of the art of doing Ada bindings is to detect/prevent errors before
they get into C, and produce segmentation faults.  And, remember that
the number of users >> the nubmer of authors for Ada bindings (and
interfaces in general.)

So, Ada bindings are a good place for your best technical people, and
often a cost-effective project for consultants.  But don't use this as
a way to train junior people, or you'll suffer the consequences for
the life of the project.

				dave
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