Re: Ada Reuse

[crispen@eight-ball.boeing.com (Bob Crispen)]

senz-steve.eng.gtefsd.com!user@ucbvax.Berkeley.EDU  (Steven Senz) sez:

>I am looking for industry/academic references for the amount of software
>reuse that one can expect in Ada.  I would like to know if there are reuse
>repositories of ada code that is accessible.  Specifically does anyone have
>actual experience in ada development with reuse software and what
>percentage of the total project was accounted for by reuse.  Any
>information would be appreciated

There are indeed public Ada repositories and semi-public repositories.
The question is, though, what is the process you will be using in order
to reuse software assets?

Will you, for example, browse though the repository until you find
something that "sorta looks like" what you had in mind?  Or will you
search for projects whose requirements were most like your current
program?

How will you determine which features of the software you find were
responses to particular circumstances and therefore "re-useless" and
separate them from those parts which are general and are therefore
reusable on any sensible solution to the problem?

How, when in nearly every problem domain source code is the *least*
expensive thing to produce, do you plan to get any value from a
repository that contains only source code?

Once you find a software asset in the repository and adapt it for your
particular program, how will you repeat that process?  Or will the
reuse activity always involve groping in the dark by highly-paid
software experts?

If you're talking about reuse as a way of life for your company, then
I think you have to answer all these questions.  If you're only
interested in getting ahold of some nifty algorithms, then maybe
you should be asking why your education has failed to prepare
you to generate these algorithms yourself (cf. introductions to
Knuth's _Art_).

Does Ada itself facilitate reuse?  Surely the most elementary text
will mention the Ada features that *can* facilitate reuse.  But
since reuse is a human activity, and since the process that real people
and real companies use to achieve reuse varies from the uneconomical
"looking for shells on the beach and hammering them until they fit"
to well-defined, repeatable processes, I hope you see that the question
as posed is nonsensical, or that at any rate it measures the goodness
of the reuse process, rather than the goodness of Ada.
+-------------------------------+--------------------------------------+
| Bob Crispen                   |   Who will babysit the babysitters?  |
| crispen@foxy.boeing.com       +--------------------------------------+
| (205) 461-3296                |Opinions expressed here are mine alone|
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