Date: Mon, 11 Mar 1996 10:35:21 -0800 (PST)
From: Mark Crispin <MRC@Panda.COM>
Sender: Mark Crispin <mrc@Ikkoku-Kan.Panda.COM>
Subject: re: Free insertion of linear-white-space
To: John Gardiner Myers <jgm+@CMU.EDU>
Cc: drums@cs.utk.edu
In-Reply-To: <AlF6ppm00WBw412NlI@andrew.cmu.edu>
Message-Id: <MailManager.826569321.18793.mrc@Ikkoku-Kan.Panda.COM>
Mime-Version: 1.0
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On Mon, 11 Mar 1996 13:14:13 -0500 (EST), John Gardiner Myers wrote:
> But anyway, instead of arguing how to interpret this dark corner of
> 822, why don't we take the practical approach.

That's better, since you are reading something into that paragraph that was
not intended.  This was a topic of long discussion in the working group.

> Existing
> implementations don't generate whitespace between the field-name and
> colon and many existing implementations can't handle whitespace
> between the field-name and colon.

I've encountered such implementations.  I don't think you can say it never
happens, just that it is rare.

I have no problem with banning this practice; however, it should be of the
form "don't do it, but you should parse it if you see it".

> Same thing goes for whitespace
> inside the domain.

This, I am pretty sure, was banned, although I forget where.  It may have been
during the days when DCA could administratively ban protocol syntax that they
didn't like, and such acts took precedence over any document.

The best way to do accomplish this ban is to remove all the domain and domain
literal syntax rules (which are wrong anyway!) from 822bis.  This can be done
quite simply by taking ".", "[", and "]" out of specials.  I have done so in
my parser, or rather, I have two separate specials; the one I use for parsing
and the one I use for generating.

It does not matter that 822bis permits
	blurdybloop@]sara[.soop.
or not.  Separate rules for DNS syntax as applied to mail suffice to ban this
practice, and since those rules may need tweaking for IPV6 anyway we might as
well get them all vestiges of them out of 822bis.  You can't implement DNS
names in a vacuum using just 822.

The one catch is the silly ban on trailing "." in the domain name.  I always
felt that this was a mistake, although Host Requirements reiterates it.  I
don't think that it belongs in 822bis, but it needs to be stated somewhere.