FW: XML 1.0 Fifth Edition is a W3C Proposed Edited Recommendation (Call for Review)

 

-----Original Message-----
From: chairs-request@w3.org [mailto:chairs-request@w3.org] On Behalf Of
Ian B. Jacobs
Sent: Wednesday, 2008 February 06 9:34
To: w3c-ac-members@w3.org
Cc: chairs@w3.org
Subject: XML 1.0 Fifth Edition is a W3C Proposed Edited Recommendation
(Call for Review)

Dear Advisory Committee Representative,

W3C is pleased to announce the advancement of "Extensible Markup
Language (XML) 1.0 (Fifth Edition)" to Proposed Edited Recommendation:
 http://www.w3.org/TR/2008/PER-xml-20080205/

in response to a transition request [1] from the XML Core Working Group.
Please review the specification and indicate whether you endorse it as
W3C Recommendation or object to its advancement by completing the
following questionnaire:
  http://www.w3.org/2002/09/wbs/33280/xml105e/

This version of the XML 1.0 specification contains one major change,
to the definition of names, bringing one major benefit of XML 1.1 into
XML 1.0.  The background to this change is set out in detail below, as
well as in the questionnaire itself.  Please take the time to read
this, and to respond, as your opinion on this change is particularly
important.

Replies are due by 23:59, Boston time on 2008-05-16.

More information about the XML Core Working Group is available at:
  http://www.w3.org/XML/Core/

If you should have any questions or need further information, please
contact Henry S. Thompson <ht@w3.org>, XML Core Working Group Team
Contact.

This Call for Review follows section 7.4.4 of the W3C Process Document:
  http://www.w3.org/2005/10/Process-20051014/tr#cfr-edited

For Tim Berners-Lee, Director;
Ian Jacobs, Head of W3C Communications

[1] http://lists.w3.org/Archives/Member/chairs/2008JanMar/0020

----------
Background
----------

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 circle, 
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 means by which to achieve the main
goal of XML 1.1, that is, to deliver on XML's original promise of
universality across all the world's languages, the XML Core WG
proposes to change XML 1.0 to relax the restrictions on names, thereby
providing in XML 1.0 the major end user benefit currently achievable
only by using XML 1.1, and completing the decoupling XML from specific
versions of Unicode.

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 continued its efforts to add scripts and
characters in order to improve or add support for the world's
languages and writing systems. This effort that is by no means
complete. The changes since the XML 1.0 name character inventory was
fixed encompass a variety of additions to the Unicode standard, and
include support for:

 * additional scripts, including Ethiopic, Cherokee, Canadian
   Syllabics, Khmer, Mongolian, Yi, Philippine, New Tai Lue, Buginese,
   Syloti Nagri, N'Ko, and Tifinagh

 * many additional Han ideographs (used predominantly for Chinese)

 * additional characters for scripts that were incompletely understood
   at the time 2.0 was released, notably scripts native to South Asia

The proposed change to XML 1.0 will relax the restrictions on names,
used not only for element and attribute names but also identifiers and
enumerated attribute values.  Those who prefer to retain the
constraints on names from the previous version of XML 1.0 in their
documents will be free to do so, but those who wish to use names that
incorporate these additional characters will be able to do so.

-----------------
Process Questions
-----------------

The Process Document sets certain requirements for a spec. to be
published as a Proposed Edited Recommendation, particularly as regards
the kinds of changes it involves and evidence of interoperability.

The changes in XML 1.0 5th Edition fall into class 3 from
section 7.6.2 Classes of Changes to a Recommendation [2], as
they affect conformance without introducing new features.

As regards the Process requirement for implementation experience, the
XML Core WG understands that implementing this relaxation in XML 1.1
parsers has been technically straightforward: it is a matter of
replacing a rather large "permitted" table with a much smaller
"forbidden" table.  The interoperability of those parsers provides the
necessary evidence that interoperable implementation of the changes
proposed in XML 1.0 5th edition will likewise be straightforward.
Conclusion

We have brought this forward because we believe the benefits outweigh
the
costs, based on a number of efforts to sample the likely response.
But the most important sample is the W3C Advisory Committee---we very
much need to hear from you on this issue.

[2] http://www.w3.org/2005/10/Process-20051014/tr#correction-classes

-- 
Ian Jacobs (ij@w3.org)   http://www.w3.org/People/Jacobs/
Tel:                     +1 718 260-9447

Received on Wednesday, 6 February 2008 15:44:48 UTC