Re: <title> containing markup

Hi, Cameron-

Cameron McCormack wrote (on 3/22/09 5:30 AM):
> One aspect of SVG-in-text/html that we discussed recently was that we
> would request that<title>  be parsed as RCDATA.  Sam Ruby points out
> that SVG 1.1 states that<title>  “can contain marked-up text from other
> namespaces”[1].  I don’t think I remembered/realised that SVG 1.1 said
> that at the time.  SVG Tiny 1.2, on the other hand, says that it must
> contain just text.  Does this impact our decision?

No, it doesn't impact it.  I knew at the time that the content of both 
<title> and <desc> could contain markup in SVG 1.1, but that it was 
underspecified.  After looking at the existing capabilities of existing 
SVGT1.2 UAs, only a minority of them handled markup other than SVG, so I 
judged that *for Tiny* (which is more targeted at devices with limited 
resources) it made sense to restrict the content of <title> to text, 
which would give us a clear way of handling the content.  I always 
planned that for SVG 2.0, we would allow markup, as we do in SVG 1.1, 
but with a clearer model for handling it.

I don't think we need to go down the absolutist path of HTML5, though, 
where we restrict what markup can be used and explain exactly how to 
parse it.  Most other languages are grown-ups, and can describe for 
themselves how they need to be handled.  We could explicitly mention how 
some particularly useful languages (X/HTML, DocBook, RDF, XSL) might be 
dealt with, and make a general rule that only text-container elements 
should be used (no images or iframes, no script excution, etc.), no 
matter what the hosted language is.  For <desc>, at least, this should 
also included traditional structured-text elements, like paragraphs and 
lists.


> I’m wondering also if someone could tell me the exact i18n problems
> allowing markup rather than plain text solves.  Do the Unicode bidi
> control characters (like RLE, PDF, etc.) not allow you to do everything
> you need to?  If there isn’t a compelling reason here to allow markup,
> then I’m in favour of keeping our request for it to be parsed as RCDATA
> in HTML 5.

We should bring in an i18n person to advise us here.

One factor in favor of allowing markup is having a single clear model 
used for both <title> and <desc>.

Regards-
-Doug Schepers
W3C Team Contact, SVG and WebApps WGs

Received on Sunday, 22 March 2009 18:08:50 UTC