Re: System.Address'Size - not a static integer expression?

[dewar@gnat.com (Robert Dewar)]

Wes Groleau <wesgroleau@despammed.com> wrote in message news:<3CB74D37.973A4C19@despammed.com>...

> In the Ada RM it doesn't.  But to a lot of people
> (and formerly, to me) that's what it meant.

Only very casually, because, as I noted before "known at
compile time" is obviously a recursively undecidable
predicate, and if you think for a moment, you know that
no language feature could be based on a RU predicate.

> It wasn't in 4.9  For me to prove I'm right, I'd have to
> find it again, which would be hard.  For you to prove I'm
> wrong, you'd have to make me read every paragraph in the 
> RM and agree it isn't in there, which would be even 
> harder. So I think we should drop it.

Not with you leaving FUD on this issue. I know the RM well
in this area, and can assure you that you did not find what
you remember. Given your confusion on the meaning of static
I would say that you should hesitate to trust your memory
here. Once again, it is of COURSE the case that 'Size is
sometimes static, and sometimes non-static. There is no
statement in the RM that contradicts this, and if there
were such a statement, it would be an obvious (and very
visible mistake), so the fact that no one has pointed out
such a mistake in the ongoing review process should really
help to convince you that your memory is faulty here.

> > > So you are saying that it IS in this subset
> > > if the prefix is a static scalar subtype?
> > 
> > Yes :-) several times
> 
> If that's true, both GNAT and Apex were wrong to reject
> the code I was speaking of.  And I severely 
> misinterpreted the RM passage that seemed to justify the 
> rejection.

No, the type in question was not a static scalar subtype!
If you still don't understand this, reread the definition 
in 4.9.