Re: A simple ADA puzzle (I haven't the answer)

["Randy Brukardt" <randy@rrsoftware.com>]

"Christoph Karl Walter Grein" <AdaMagica@web.de> wrote in message
news:mailman.119.1087461544.391.comp.lang.ada@ada-france.org...
> From: "Dmitry A.Kazakov" <mailbox@dmitry-kazakov.de>
> > As for Ada strings, there are only two problems related:
> >
> > 1. The default values for discriminants shall not have any implicit
> > effects on the memory allocation policy. That was a mistake of Ada 83.
>
> This syntax was defined exactly for this purpose. So it's _not_ a mistake.
You may argue whether
> that was a clever choice. But there is no other use for the default
discriminant than allowing
> discriminant changes. An alternative would have been to use a special
reserved word. They tried
> to minimize the number of reserved words and used solutions with special
syntax wherever possible.

I have to agree with Dmitry. Tying "defaulted discriminants" to "mutable
objects" was an awful mistake in Ada 83. It caused Tucker Taft and the rest
of the Ada 95 design team no end of trouble, and it has continued to cause
the ARG trouble. They're separate concepts, and they should have been
handled separately. I think most of the ARG would agree with this opinion (I
*know* Tucker would).

                    Randy.