W3C home > Mailing lists > Public > www-svg@w3.org > September 2008

Re: values of requiredExtensions to use XHTML/MathML (ACTION-2193 ISSUE-2053)

From: Doug Schepers <schepers@w3.org>
Date: Thu, 18 Sep 2008 00:07:48 -0400
Message-ID: <48D1D414.6050002@w3.org>
To: www-svg@w3.org

Hi, Frédéric-

Frédéric WANG wrote (on 9/17/08 6:57 PM):
> Thanks, It's clearer now.

My pleasure.

> I have thought about another issue since the last time: it is possible
> that the browser needs several languages to display a foreignObject. For
> instance, attachment xhtml+mathml+svg.xml contains an SVG image with an
> embedded XHTML paragraph, and some MathML formulae in this paragraph.
> Does "a list of required language extensions", means "the list of *all*
> the required languages" ? Or simply of the languages used for the
> children of the foreignObject (here, XHTML). Amaya generates the latter,
> but I don't know what is better for interoperability. For the moment,
> the new wording is good for me.

'requiredExtensions' is optional, and merely serves to let the author
test against the extensions that the author sees as necessary to view
the content, and otherwise to hide it or provide an alternative (if
using <switch>).  It can contain as many or as few extension IRIs as the
author deems useful, and may or may not have anything to do with
<foreignObject> or the child content.

> Just a small typo: the attribute name is requiredExtensions (with a s )
> not requiredExtension.

D'oh.  Note to self... get more than 3 hours of sleep the night before
writing examples you expect to have people copy. :P

Should be fixed now.

> Also, Ishikawa Masayasu proposed a DTD for  XHTML+MathML+SVG (
> http://www.w3.org/TR/XHTMLplusMathMLplusSVG/ ). It's a working draft but
> it is currently the only rules we have and they are integrated in the
> W3C validator. Hence I think you should try to validate the two last
> examples against this DTD.

I just tried it, but as I feared, that part of the Validator is
DTD-based, and not as reliable or useful as I think is needed.  Maybe we
need to come up with an updated draft of that document, and base the
Validator on more modern technologies like RelaxNG, Schema, and NVDL.

-Doug Schepers
W3C Team Contact, SVG and WebApps WGs
Received on Thursday, 18 September 2008 04:08:22 UTC

This archive was generated by hypermail 2.3.1 : Wednesday, 8 March 2017 09:47:15 UTC