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Re: Proposal for Guideline 1.1 [definition of text]

From: Christophe Strobbe <christophe.strobbe@esat.kuleuven.be>
Date: Tue, 24 May 2005 16:28:46 +0200
Message-Id: <6.0.0.22.2.20050524162820.02fd7370@mailserv.esat.kuleuven.be>
To: w3c-wai-gl@w3.org

Hi,

At 04:35 27/04/2005, Wendy wrote:
>Attached is an html file with the issue summary for Guideline 1.1 as well as proposed text for the guideline and related definitions. 
>(...)


<blockquote>
text

       Proposed definition: A sequence of characters. Characters are
   those included in the Unicode / ISO/IEC 106464 repertoire. Refer to
   Characters (in Extensible Markup Language (XML) 1.1) for more
   information about the accepted character range.

       [@@what about functional text content? e.g., links?] [@@refer to
   XML 1.0 or 1.1 - Christophe felt 1.0 is safer, but yet it's dated
   and not as "internationalized" - ala Richard's talk at the Technical
   Plenary]

       Current definition: none
</blockquote>

My reasons for avoiding a reference to XML 1.1 are the following:
- XML 1.1 is not backward compatible with XML 1.0: XML 1.1 requires that
control characters #x7F through #x9F, which were freely allowed in XML 
1.0 documents, now must also appear only as character references, and
it allows the control characters #x1 through #x1F, most of which are 
forbidden in XML 1.0, through the use of character references.
- Because XML 1.1 is not backward compatible, the XML WG recommended 
that "that applications that produce XML documents keep using XML 1.0 
as much as possible, and only use XML 1.1 when necessary" [1].
- XML 1.0 is less "internationalised" only in important parts of XML 
such as element and attribute names, enumerated attribute values, or
processing instruction targets, but characters that were not present 
in Unicode 2.0 (the Unicode version that XML 1.0 referred to) can be 
used in XML 1.0 character data. Since we are talking about the definition 
of text (i.e. not markup such as element or attribute names) there is
no need to refer to XML 1.1. More importantly, because of the 
compatibility issue, I would like to avoid the impression that WCAG 
recommends XML 1.1 over XML 1.0.

If there are concerns about the accepted character range in a document,
these can be covered by guideline 4.1 (use technologies according to
specification).

Joe Clark [2] and Mike Barta [3] have argued that there is no need to as to
require that characters exist in the Unicode standard.
The following definition avoids both the references to XML 1.0/1.1 and
Unicode:

text
     Proposed definition:
     Any sequence of characters that exist in the writing systems of
     the world's natural languages.

Note: this does not mean that programming code is not text, because
programming code is written with characters that already exist in
a writing system.



<blockquote>
unicode

       Proposed definition: Unicode is a universal character set that
   defines all the characters needed for writing the majority of living
   languages in use on computers. For more information refer to the
   Unicode Consortium or to Tutorial: Character sets & encodings in
   XHTML, HTML and CSS produced by the W3C Internationalization
   Activity. [Additional optional clarification: This does not mean
   that all documents should be encoded in Unicode. It means that
   documents should only contain characters defined by Unicode. Any
   encoding may be used for your document as long as it is properly
   declared and is a subset of the Unicode repertoire. ]

       Current definition: none.
<blockquote>

I find the inclusion of the additional clarification useful.

I apologise for the late response; I hope these comments are still 
useful.

Best regards,

Christophe



[1] http://www-128.ibm.com/developerworks/xml/library/x-xmlns11.html
[2] http://lists.w3.org/Archives/Public/w3c-wai-gl/2005AprJun/0211.html
[3] http://lists.w3.org/Archives/Public/w3c-wai-gl/2005AprJun/0320.html
Received on Tuesday, 24 May 2005 14:29:22 UTC

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