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Re: Definition of NCName for version 1.0 and 1.1

From: Henry S. Thompson <ht@inf.ed.ac.uk>
Date: Thu, 22 Oct 2009 12:44:04 +0100
To: David Matson <dmatson@microsoft.com>
Cc: "xml-names-editor@w3.org" <xml-names-editor@w3.org>
Message-ID: <f5bws2ny7p7.fsf@hildegard.inf.ed.ac.uk>
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David Matson writes:

> With the Fifth Edition of XML 1.0, the definition of Name has been made
> consistent with version XML 1.1. However, the definition of NCName still
> differs between Namespaces in XML 1.0 (Second Edition, per errata) and
> Namespaces in XML 1.1 (Second Edition).

Only in the way the definition is expressed, not in substance.

> The 1.0 version has (in the errata):
>
> [4]    NCName    ::=    Name - (Char* ':' Char*) /* An XML Name, minus the
> ":" */
>
> With NCNameChar and NCNameStartChar moved to a new appendix:
>
> [5]    NCNameChar    ::=    NameChar - ':' /* An XML NameChar, minus the ":"
> */ 
>
> [6]    NCNameStartChar    ::=    NCName - ( Char Char Char* ) /* The first
> letter of an NCName */
>
>  
>
> The 1.1 version has:
>
> [4]    NCName    ::=    NCNameStartChar NCNameChar* /* An XML Name, minus
> the ":" */ 
>
> [5]    NCNameChar    ::=    NameChar - ':' 
>
> [6]    NCNameStartChar    ::=    NameStartChar - ':'
>
>  
>
> Since both versions of XML now define Name identically, it seems odd that
> the corresponding Namespaces specifications would define NCName differently.

The Working Group is entirely in agreement with your analysis.

However, the problem is that we need the definitions in XML NS 1.0 3e
to work _regardless_ of which edition of XML 1.0 they are interpreted
against.  That is, it is perfectly OK to combine XML NS 1.0 3e with
XML 1.0 4e.  But XML 1.0 4e (and earlier editions) do not _have_ a
NameStartChar production.

So what we've got is the best we can do, sorry.

Please let us know if you can live with this resolution of your issue.

ht
- -- 
       Henry S. Thompson, School of Informatics, University of Edinburgh
                         Half-time member of W3C Team
      10 Crichton Street, Edinburgh EH8 9AB, SCOTLAND -- (44) 131 650-4440
                Fax: (44) 131 651-1426, e-mail: ht@inf.ed.ac.uk
                       URL: http://www.ltg.ed.ac.uk/~ht/
[mail really from me _always_ has this .sig -- mail without it is forged spam]
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Received on Thursday, 22 October 2009 11:44:35 GMT

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