Re: Fallback for broken references.

Hey Jim,

On Mon, 28 Oct 2002, Jim Ley wrote:

> In SVG, you can include content from one document in another, this is
> very useful of course, the problem comes that when it fails, we get no
> indication of anything going wrong, meaning you can get odd results if
> the link is broken (perhaps because the SVG was saved locally, or the web
> connection broke mid transfer)
> 
> The meaning of a document can radically change. I've got a rather
> contrived Llama demo <URL: http://jibbering.com/2002/8/thellamas.svg > *
> which gives a very different message in Batik and ASV (which doesn't
> support external TREF's). Dean Jackson's SVG to text converter also
> demonstrates the problem which shows how much cleverer SVG Access
> Technologies need to be due to the ability to refer to external
> documents, although the TEXT to HTML at least makes the user aware.
> 
> I'm not sure what suggestion to make, perhaps even just require user
> agents to make the user aware that some content is missing, as the
> duplicating of fallback content rather defeats the object.

You've raised interesting points here.
The SVG Working Group discussed this issue and have decided
to examine potential solutions in SVG 1.2.

> * but not as contrived as the cat/mat demo.

We'll look forward to using that one as an example in the spec.

Dean