Re: Required Metrics

[Ole-Hjalmar Kristensen <ohk@clustra.com>]

Robert Dewar <robert_dewar@my-deja.com> writes:

> In article <24VQ4.8453$wb7.646902@news.flash.net>,
>   "Ken Garlington" <Ken.Garlington@computer.org> wrote:
> > By the way, while writing up a bug report, I found this in the
> gnatinfo.txt
> > file...
> >
> > "The Documentation for GNAT consists of two manuals, the GNAT
> User's Guide
> > and the GNAT Reference Manual. These are available in a number
> of formats
> > (ASCII, HTML, PostScript and info) and are bundled as a
> separate
> > documentation
> > distribution and can be found at the same places as the GNAT
> binary and
> > source distributions."
> >
> > ...and I just had to laugh!
> 
> 
> By the way, the documentation for GNAT very definitely
> includes the Ada Reference Manual -- but perhaps that's a
> surprise to Ken too ... hard to tell!
> 
> This thread is quite instructive.
> 
> I think the entire problem is that in the realm of software
> engineering, you define a set of "requirements", and then
> you can tell whether you have done a good job of implementing
> the software by seeing if it meets these requirements.
> 
> It is, I guess, quite understandable, if quite wrong, for people
> to make the mistake of thinking that a language definition is
> like such a requirements document, and that you will be able
> to tell if a vendor has done a good job of writing an Ada
> compiler by seeing if it has met these requirements.
> 
> That's quite wrong of course, the defining language document
> is not a set of requirements in this sense at all. Well more
> properly it is a small part of the requirements. Left out
> entirely are issues of performance, reliability, efficiency,
> usability, maintainability etc etc.

But it *is* the definition of the language. In that case, it is the
*minimum* requirement if you want a complete implementation.

> 
> By the way Ken, you questioned me saying that you were one of
> the people arguing for inclusion of these ill-defined
> requirements in the language. I may remember wrong, but I
> distinctly remember you arguing for this approach in the
> meetings we had on safety-critical requirements, and your
> previous post seems to confirm that memory (the one where
> you say that it was a waste of time attending that meeting).
> 
> I sure hope that SOME people reading this thread come away with
> a little bit better understanding of what language definitions
> are all about (and also an understanding of why validation
> cannot guarantee usability or quality).
> 
> 
> 
> Sent via Deja.com http://www.deja.com/
> Before you buy.

-- 
E pluribus Unix