From: "Randy Brukardt" <randy@rrsoftware.com>
Subject: Re: Dynamic Variant Record Creation
Date: Wed, 17 Mar 2010 19:13:04 -0500
Date: 2010-03-17T19:13:04-05:00 [thread overview]
Message-ID: <hnrr6j$d7n$1@munin.nbi.dk> (raw)
In-Reply-To: a4de16f2-1b14-4c9d-886a-2e61f6c01863@k6g2000prg.googlegroups.com
"Adam Beneschan" <adam@irvine.com> wrote in message
news:a4de16f2-1b14-4c9d-886a-2e61f6c01863@k6g2000prg.googlegroups.com...
On Mar 16, 4:39?pm, "Randy Brukardt" <ra...@rrsoftware.com> wrote:
...
>This has to use the same sort of case statement to initialize the
>components in the variant parts. So I thought that basically the code
>would be using the same logic, plus assigning initial values to the
>non-variant components.
As noted to Bob, that doesn't work in Janus/Ada. There also is a critical
limitation on our intermediate code: there cannot be case statement-like
control structures in expressions (we completely separate control flow and
values in the intermediate code; there cannot be live values when there is
control flow and vice-versa; values have very limited control flow
possibilities from short circuit operations and loop initializers).
If the idea offered much additional expressiveness, I wouldn't object, but
it doesn't seem to have enough.
Steve Baird and I had worked out a partially constrained discriminant
constraint which would have provided a much better solution to this problem
along with many others -- but Tucker Taft couldn't seem to wrap his mind
around the idea (it seemed natural to me) and thus it got quickly killed.
Thus I don't think there will be any relief.
Randy.
P.S. It probably isn't fair to single out Tucker for killing the idea, but
since he usually has a much more flexible view of the world, it was bizarre
that he couldn't understand it. I suspect many took that as an indication
that it was fatally flawed; I suspect the problem more was one of
presentation.
next prev parent reply other threads:[~2010-03-18 0:13 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-03-16 17:11 Dynamic Variant Record Creation Warren
2010-03-16 18:31 ` Georg Bauhaus
2010-03-16 18:57 ` Adam Beneschan
2010-03-16 20:01 ` Warren
2010-03-16 20:09 ` Jeffrey R. Carter
2010-03-16 20:24 ` Warren
2010-03-16 20:40 ` Robert A Duff
2010-03-16 20:44 ` Warren
2010-03-16 20:31 ` Robert A Duff
2010-03-16 20:59 ` Warren
2010-03-16 21:55 ` Jeffrey R. Carter
2010-03-17 14:40 ` Warren
2010-03-18 12:57 ` Warren
2010-03-16 21:58 ` Robert A Duff
2010-03-17 14:22 ` Charmed Snark
2010-03-17 14:49 ` Robert A Duff
2010-03-17 16:30 ` Warren
2010-03-16 21:15 ` Adam Beneschan
2010-03-16 23:24 ` Adam Beneschan
2010-03-16 20:15 ` Robert A Duff
2010-03-16 21:00 ` Warren
2010-03-16 23:39 ` Randy Brukardt
2010-03-16 23:43 ` Randy Brukardt
2010-03-17 0:15 ` Robert A Duff
2010-03-17 14:28 ` Warren
2010-03-18 0:02 ` Randy Brukardt
2010-03-17 4:20 ` Adam Beneschan
2010-03-18 0:13 ` Randy Brukardt [this message]
2010-03-18 13:00 ` Warren
replies disabled
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox