Path: utzoo!utgpu!water!watmath!clyde!rutgers!cmcl2!brl-adm!brl-smoke!gwyn
From: gwyn@brl-smoke.ARPA (Doug Gwyn )
Newsgroups: comp.lang.c
Subject: Re: Noalias considered unreadable, let alone a bad idea
Message-ID: <7181@brl-smoke.ARPA>
Date: 25 Jan 88 22:33:25 GMT
References: <7072@brl-smoke.ARPA> <7160@brl-smoke.ARPA> <3932@hoptoad.uucp>
Reply-To: gwyn@brl.arpa (Doug Gwyn (VLD/VMB) <gwyn>)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 38

In article <3932@hoptoad.uucp> gnu@hoptoad.uucp (John Gilmore) writes:
>And no place at all for things where the three people who claim to
>understand it are unable to explain it, over a protracted period,
>to the rest of us.

I don't think that's really a valid criterion; if you apply it as stated,
virtually everything in C wouldn't belong in the Standard, judging by the
misinformation in this newsgroup and elsewhere from people who claim to
understand things.

It is also not a fair criterion; for example, I was trying to explain
the concept minimally, just as a follow-up to my announcement about
changes voted in at the last meeting.  I don't actually like "noalias"
much, although (partly as Response Document editor) I feel obliged to
defend the X3J11 Committee's position.  Hence I'm not the best proponent
of this feature.  It is also possible that don't really understand
"noalias" or that I'm just not good at explaining things.  It is even
possible that "the rest of you" aren't very good at understanding things! :-)

Having said all that, I'll agree that it does appear to me that the
additional utility of having "noalias" is perhaps not worth the effort
of specifying it fully and accurately or of understanding the
specification.  It certainly is more intricate than almost any other
concept in the proposed Standard.

The issue of difficulty in implementing the specifications correctly
doesn't bother me much.  It is unlikely that there are more than a few
hundred people in the world who could reasonably be expected to produce
a high-quality C implementation anyway, and most of the ones who will
be (or are) attempting to implement the ANSI C specifications either are
on the Committee or have sufficient contacts with Committee members who
can answer questions about some of the subtler points.

If you can suggest improvements in any of the wording in the proposed
Standard, I would urge that they be sent in as comments during the next
formal public review period, which should start soon.  It would help to
make the final Standard as intelligible as possible.  (Even stating that
you find some topic confusing, unclear, or ambiguous would be helpful.)