Re: ISO/IEC 10646 as Document Character Set

Charles F. Goldfarb (Goldfarb@interramp.com)
Sun, 7 May 95 01:21:49 EDT

>
>> From: Glenn Adams <glenn@stonehand.com>
>> Date: Sat, 6 May 95 13:22:57 -0400
>>
>> Date: Sat, 6 May 95 11:31:27 EDT
>> Reply-To: jjc@jclark.com
>>
>> It is an interesting question what restrictions there are on the
>> character number [in a numeric character reference]. 13.1.1 says:
>>
>> The described character set portions must collectively describe
>> each character number in the described character set once
>> and only once.
>>
>> Given this and given that the number is a "character number", I think
>> one could argue that the number in the character reference must be one
>> that was described (even if only as UNUSED) in the document character
>> set section of the SGML declaration.
>>
>> I'm not convinced. The 13.1.1 text seems to be oriented towards preventing
a
>> single character number from being described more than once than it is
>> oriented towards requiring every character number to be described at least
>> once.
Hi all,
The sentence says, in part: "must collectively describe each character number
once". What could be clearer? There _must_ be a description for each
character number. "UNUSED" is a possible description.

As Glen points out, there cannot be more than one such description for each
character number. That is why the sentence says "once and only once". Would
"exactly once" have been clearer? To me the existing wording is superior but the
committee welcomes suggestions for the revision of 8879.

.

>I wouldn't claim my interpretation is the only one possible.
I would.

>(In fact
>it is not what the currently released version of SP implements.)
Please treat this as a bug report. :-)

>> Has this question been put to Charles or WG8?
It has now.

Best regards to all,
Charles

--
Charles F. Goldfarb * Information Management Consulting * +1(408)867-5553
   International Standards Editor * ISO 8879 SGML * ISO/IEC 10744 HyTime
--