W3C home > Mailing lists > Public > public-tt@w3.org > May 2009

Re: ISSUE-92 (xml:base): xml:base not included [DFXP 1.0]

From: Glenn A. Adams <gadams@xfsi.com>
Date: Wed, 06 May 2009 07:21:51 +0800
To: Sean Hayes <Sean.Hayes@microsoft.com>, Public TTWG List <public-tt@w3.org>
Message-ID: <C626EB0F.A767%gadams@xfsi.com>

notwithstanding my prior replies on this issue, it may be that we should
make use of xml:base on the new ttp:{extensions,features} elements where we
now have a 'base' attribute;


On 5/6/09 7:10 AM, "Sean Hayes" <Sean.Hayes@microsoft.com> wrote:

> This query comes from some colleagues of mine who are attempting to use both
> XInclude and the previous schemas. I'll point them at the new schemas, and
> this response and see how they get on and report back.
> 
> Sean Hayes
> Media Accessibility Strategist
> Accessibility Business Unit
> Microsoft
> 
> Office:  +44 118 909 5867,
> Mobile: +44 7875 091385
> 
> 
> -----Original Message-----
> From: Glenn A. Adams [mailto:gadams@xfsi.com]
> Sent: 06 May 2009 12:06 AM
> To: Sean Hayes; Public TTWG List
> Subject: Re: ISSUE-92 (xml:base): xml:base not included [DFXP 1.0]
> 
> 
> The schemas are normative in the sense that we define them as "normative".
> They are not normative in the sense of defining validiy of a DFXP document
> instance. The text in 4.1 says "validate a SUBSET...". See also the note at
> end of 4.1. [If the note is wrong about false negatives, then we need to
> tune the schemas to not complain about foreign namespace elements and
> attributes.]
> 
> Also see Appendix C which says:
> 
> "In any case where a schema specified by this appendix differs from the
> normative definitions of document type, element type, or attribute type as
> defined by the body of this specification, then the body of this
> specification takes precedence."
> 
> So, in effect, the schemas we publish are not definitive w.r.t. DFXP
> validity, which is a decision we made some time ago.
> 
> G.
> 
> On 5/6/09 7:00 AM, "Sean Hayes" <Sean.Hayes@microsoft.com> wrote:
> 
>> 4.1 seems to contradict that:
>> 
>> "This specification defines two types of normative schemas that may be used
>> to
>> validate a subset of conformant DFXP document instances:"
>> 
>> If we are going to make abstract document validity the normative one, then
>> the
>> schemas should become informative.
>> 
>> Sean Hayes
>> Media Accessibility Strategist
>> Accessibility Business Unit
>> Microsoft
>> 
>> Office:  +44 118 909 5867,
>> Mobile: +44 7875 091385
>> 
>> 
>> -----Original Message-----
>> From: public-tt-request@w3.org [mailto:public-tt-request@w3.org] On Behalf Of
>> Glenn A. Adams
>> Sent: 05 May 2009 11:51 PM
>> To: Public TTWG List
>> Subject: Re: ISSUE-92 (xml:base): xml:base not included [DFXP 1.0]
>> 
>> this is already permitted by means of section 4 item 3; so you may close
>> this issue;
>> 
>> On 5/6/09 3:20 AM, "Timed Text Working Group Issue Tracker"
>> <sysbot+tracker@w3.org> wrote:
>> 
>>> 
>>> ISSUE-92 (xml:base): xml:base not included [DFXP 1.0]
>>> 
>>> http://www.w3.org/AudioVideo/TT/tracker/issues/92
>>> 
>>> Raised by: Sean Hayes
>>> On product: DFXP 1.0
>>> 
>>> We did not include xml:base in the timed text specification, because as
>>> timed
>>> text makes no external references it was deemed unnecessary. However this
>>> may
>>> cause an unfortunate side effect making it unable to interoperate with
>>> XInclude.
>>> 
>>> The XInclude spec says:
>>> 
>>> "Each element information item in the top-level included items which has a
>>> different base URI than its include parent has an attribute information item
>>> added to its attributes property. This attribute has the following
>>> properties:
>>> .... [describes xml;base attribute]"
>>> 
>>> Since timed text has no external references, it has no base URI, so itıs not
>>> 100% clear whether the xml:base should be added as a result of this clause
>>> (and it may be suppressed by user option), however if it is (which it seems
>>> to
>>> be in practice); this would prevent the resulting dfxp document from
>>> validating against the schema.
>>> 
>>> proposal: allow xml:base on elements in the schema, but indicating that its
>>> value is ignored in the prose.
>>> 
>>> 
>>> 
>> 
>> 
>> 
> 
> 
Received on Tuesday, 5 May 2009 23:22:37 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 2 November 2009 22:41:42 GMT