W3C home > Mailing lists > Public > www-xml-stylesheet-comments@w3.org > April 2010

RE: Comments on last editor's draft of xml-stylesheet [glazman-1]

From: Grosso, Paul <pgrosso@ptc.com>
Date: Wed, 7 Apr 2010 12:18:53 -0400
Message-ID: <CF83BAA719FD2C439D25CBB1C9D1D30212E99E6D@HQ-MAIL4.ptcnet.ptc.com>
To: "Daniel Glazman" <daniel@glazman.org>
Cc: <www-xml-stylesheet-comments@w3.org>
Daniel,

The Association Style Sheets draft at
http://www.w3.org/XML/2010/03/xml-stylesheet/
is a public editor's draft of what is soon to be published
as a PER for Association Style Sheets Second Edition.
It is not in scope for us to make changes of a substantive 
nature between a first and second edition.

The XML Core WG does not feel that this specification 
should define the meaning of pseudo-attribute values
beyond the general statements currently in the draft.

The first edition already restricts xml-stylesheet
PIs to the "top" of the document; to quote:

 The xml-stylesheet processing instruction is
 allowed only in the prolog of an XML document.

As a second edition, this draft cannot change that.
Supporting scoped stylesheets is out of scope for all
editions of Association Style Sheets 1.0.

paul

> -----Original Message-----
> From: Daniel Glazman [mailto:daniel@glazman.org]
> Sent: Wednesday, 2010 March 31 23:35
> To: Grosso, Paul
> Cc: www-xml-stylesheet-comments@w3.org
> Subject: Re: Comments on last editor's draft of xml-stylesheet
> [glazman-1]
> 
> Le 29/03/10 16:55, Grosso, Paul a écrit :
> > Daniel,
> >
> > Thank you for your comment [1] on the latest Association
> > Style Sheets draft [2].
> >
> > You suggest that:
> >
> >   in the definition of the 'media' attribute, [the spec]
> >   should probably specify that if the 'media' pseudo-attribute
> >   is absent then the stylesheet applies to "all" media.
> >
> > We have tried in this spec to stay away from discussing what
> > applications do with the information in this PI.  In fact,
> > there are applications beyond browsers--including some SGML/XML
> > editors--that make use of the information in this PI and that
> > ignore such a PI if the media pseudo-attribute is omitted, and
> > there is nothing wrong with that behavior.
> >
> > The (second) Note in section 2 currently reads:
> >
> > <quote>
> > The details of how conforming xml-stylesheet processors
> > exploit the information contained in xml-stylesheet
> > processing instructions are out of scope for this document,
> > as they may reasonably vary from processor to processor.
> > </quote>
> >
> > but that is somewhat of a misstatement.  We are changing
> > that Note to read:
> >
> > <quote>
> > The details of how applications
> > exploit the information contained in xml-stylesheet
> > processing instructions are out of scope for this document,
> > as they may reasonably vary from application to application .
> > </quote>
> >
> > The xml-stylesheet processor does not exploit the information
> > in the PI at all; it passes it on to the application which
> > decides what to do with it, and what the application does
> > with it is out of scope of the Associating Style Sheets
> > specification itself.
> >
> > Please reply (cc-ing www-xml-stylesheet-comments@w3.org) as
> > to whether you accept such a resolution of your comment.
> 
> I think I don't accept it for the following reasons:
> 
> 1. I agree 100% that some applications may deal with the media
>     pseudo-attribute in a way that entirely differs from how a
>     browser handles it. In fact, an editing tool may want to
>     completely ignore the media pseudo-attribute, whatever its
>     value or even its presence/absence, because otherwise it would be
>     impossible for instance to edit on a screen a document made
>     only to be printed, or edit on a desktop computer a document
>     created for |screen and (max-device-width: 320px)|. So this is not
> a
>     good enough reason to avoid specifying what means the absence of
> the
>     media pseudo-attribute.
> 
> 2. the document specifies the media pseudo-attribute anyway. If
>     you want to entirely leave the processing to the document
> processor,
>     then you should say that the PI has pseudo-attributes defined by
>     whatever the document language needs to process the link to the
>     stylesheet. The only pseudo-attribute defined by this spec should
>     be href then. Possibly the mediatype but I'm not even sure since
>     some document languages may decide to authorize only CSS and not
>     XLST, why not after all...
> 
> 3. we have only two stylesheet languages on the web usable with this
>     PI and as far as I know, only CSS has the notion of rendering
> media.
>     CSS itself will NOT deal with the specification of the media pseudo
>     attribute, obviously. In particular, it must not specify what's
>     happening if it's absent. This could belong to the document's
>     language. But then the absence or presence of the media pseudo-
>     attribute has an unpredictable behaviour from the POV of a filter
> or
>     transformation tool that has no knowledge of that specification.
>     Let's imagine I have a XML document conformant to a given schema;
>     that XML dialect specifies that the absence of media means media=
>     "screen" and we want to transform that document on the fly into
>     XHTML. A generic filter is then unable to infer that it should
>     create a media="screen" (pseudo-)attribute in the PI or <link>
>     element in the XHTML result instead of leaving it unspecified.
>     Furthermore, there is wide common practice about the media (pseudo-
> )
>     attribute used in the <link> element and the existing stylesheeet
>     PI. Its absence is a synonym to media="all". The current draft
>     breaks it.
> 
> 4. saying the absence of the media pseudo-attribute is a synonym to
>     media="all" (please note I am not saying it's a default value)
>     does not say anything about how a processor should handle it.
>     It is still up to the user agent and is not inconsistent, in my
>     opinion, with the spirit of this draft.
> 
> While we're at it, I just discovered that, unless I did not understand
> the 1st paragraph of section 4, the stylesheet PI remains
> usable only at the top of the document. If that's the case, I think
> this limitation should be lifted to allow scoped stylesheets. I
> recommend taking a look at what HTML5 does on that topic. If you need a
> separate message about this to register this comment, please let me
> know. Please note that a |scoped| pseudo-attribute may be needed in
> that case.
> This comment is of course of no value if I misunderstod that section,
> in which case I apologize for that.
> 
> </Daniel>
> --
> W3C CSS WG, Co-chair
Received on Wednesday, 7 April 2010 16:20:26 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Wednesday, 7 April 2010 16:20:27 GMT