Bidi - BN - clarifying suggestion

"Martin J. Dürst" duerst at
Tue Sep 8 09:17:10 CEST 2009

Hello John,

Thanks for your proposals. However, as I'll explain below, they don't 
exactly address the concerns that I had.

On 2009/09/08 1:07, John C Klensin wrote:
> Hi.
> I've just taken a careful look at the bidi doc wrt the BN issue
> and suggest that one of the two suggestions that follow might
> help to clarify things without changing anything of importance.
> Either (rewrites at the discretion of the editors, obviously)...
>      (1) Add an additional sentence to the end of bullet (2) of
>      Section 2:
>      Note that many of these characters, especially most of those
>      in BN, are DISALLOWED by [Tables].

At least from my background, it is emphatically NOT necessary to point 
out that most of BN (control characters) are disallowed. The reason I 
started this whole discussion was that it was difficult for me to 
imagine ANY control character to be allowed. That's why I still strongly 
believe that the reader is most helped by pointing out some concrete 
cases of BN that are actually allowed.

> or
>      (2) Add the following to the end of the introductory
>      paragraph of Section 2:
>      Passing the BIDI test is not sufficient for a label
>      containing applicable characters to be valid because many of
>      the labels that would pass this test would still be invalid
>      because they contain characters that are DISALLOWED
>      [Tables], or that must satisfy context-dependent rules that
>      are not met [Protocol].
> Now, I am convinced that the above clarifications don't change
> anything -- the relevant rules are enforced by Protocol whether
> Bidi is invoked or not.  But, if the inclusion of, e.g., BN, in
> the Bidi-valid list has confused some of us, it is much more
> likely to confuse others.

I'm likewise convinced that the above doesn't change anything normative. 
But I'm also convinced that they don't actually help anything. The Bidi 
document is already clear that it relates to Bidi, and nothing else.

And as far as I understand, I was the one who was confused. "Somebody is 
confused, so let's do something about it" is a good intent, but it 
doesn't help if instead of addressing the actual confusion/question, 
something vaguely related is "clarified" in the spec.

Regards,    Martin.

#-# Martin J. Dürst, Professor, Aoyama Gakuin University
#-#   mailto:duerst at

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