FW: XML 1.0 and XML 1.1

Hi all,

Some request for comments on a possible change of XML 1.0 (related to Unicode).
Please send comments to www-xml-blueberry-comments@w3.org (publicly archived).
 
Cheers,
-yves


-----Original Message-----
From: chairs-request@w3.org [mailto:chairs-request@w3.org] On Behalf Of Grosso, Paul
Sent: Monday, October 29, 2007 9:20 AM
To: chairs@w3.org
Subject: XML 1.0 and XML 1.1


Chairs,

Please feel free to forward this email to your WGs.  (Public W3C mailing lists are fine--this is not intended to be member-only.)

paul

------

Since XML 1.1 became a W3C Recommendation in August 2006, there has been a substantial uptake of it as a peer of XML 1.0 in new and
ongoing W3C work.  This is appropriate, as XML 1.1 was explicitly not designed to replace XML 1.0, but to supplement it for the
benefit of various groups against which XML 1.0 had unjustly, but unintentionally, discriminated.

However, there are very few XML 1.1 documents in the wild.  
The XML Core WG believes this to be the result of a vicious cycle, in which widely distributed XML parsers do not support 1.1
because the parser authors believe that few document authors will use it.
This becomes a self-fulfilling prophecy, as those who would benefit from XML 1.1 are rightfully concerned that documents written in
it will not be widely acceptable.

After considering various other ideas, the XML Core WG wants to suggest the possibility of changing XML 1.0 to relax the
restrictions on element and attribute names thereby providing in XML 1.0 the major end user benefit currently achievable only by
using XML 1.1.

To quote the XML 1.1 Recommendation:

 The W3C's XML 1.0 Recommendation was first issued in 1998,  and despite the issuance of many errata culminating in a  Third Edition
of 2004, has remained (by intention) unchanged  with respect to what is well-formed XML and what is not.
 This stability has been extremely useful for interoperability.
 However, the Unicode Standard on which XML 1.0 relies for  character specifications has not remained static, evolving from
 version 2.0 to version 4.0 and beyond.	Characters not present
 in Unicode 2.0 may already be used in XML 1.0 character data.
 However, they are not allowed in XML names such as element type  names, attribute names, enumerated attribute values, processing
instruction targets, and so on.  In addition, some characters  that should have been permitted in XML names were not, due to
oversights and inconsistencies in Unicode 2.0.

 The overall philosophy of names has changed since XML 1.0.
 Whereas XML 1.0 provided a rigid definition of names, wherein  everything that was not permitted was forbidden, XML 1.1 names are
designed so that everything that is not forbidden (for a specific
 reason) is permitted.  Since Unicode will continue to grow past  version 4.0, further changes to XML can be avoided by allowing
almost any character, including those not yet assigned, in names.

Since then, Unicode has expanded further to reach 5.0, and it is nowhere near complete with respect to the world's minority
languages and writing systems.  If XML 1.0 relaxed the restrictions on element and attribute names, those who preferred to retain
the Appendix B constraints in their documents would be free to do so, but those who wish to use element and attribute names in
languages normally written in any of the Ethiopic, Cherokee, Canadian Syllabics, Khmer, Mongolian, Yi, Philippine, New Tai Lue,
Buginese, Syloti Nagri, N'Ko, and Tifinagh scripts will be able to do so, as will users of minority languages whose scripts appeared
in Unicode 2.0 but were lacking essential letters for writing those languages.

Of course, older parsers will still reject such documents, but there will be no need for a strict XML 1.0/1.1 dichotomy.  The XML
Core WG has heard evidence tending to indicate that implementing such a relaxation would be technically straightforward in
essentially all XML parsers:  it is a matter of replacing a rather large "permitted" table with a much smaller "forbidden" table.

The XML Core WG assumes that if such an erratum were to be passed into XML 1.0, the XML 1.1 Recommendation would eventually be
deprecated by the W3C.

Comments on all aspects of this possibility are earnestly solicited; please send them to www-xml-blueberry-comments@w3.org (publicly
archived).

Paul Grosso
for the XML Core WG

Received on Monday, 29 October 2007 16:34:43 UTC