Re: Format Negociation in Practice [Was: Versioning HTML at the server]

Joe English (jenglish@crl.com)
Wed, 19 Oct 1994 17:45:52 +0100

Earl Hood <ehood@imagine.convex.com> wrote:

> [jenglish@crl.com wrote:]
> > How about parameters on the Accept: header?
> > [...]
> > This should require a minimal change to browsers,
> > as the HTML features supported by a browser are
> > more or less fixed.
>
> The main problem I see with this solution is that it is HTTP specific.
> HTML is an SGML application. I believe it is best that a solution is
> targeted more in the SGML realm so authors have more control on how a
> document will appear based upon a client's conformance level.

Browser support for marked sections is clearly
desirable, for this and other reasons. I'm
not holding my breath though; two of the three
browsers I use don't even get comment declarations
right yet.

> Plus not
> all HTML documents are served via HTTP.

True, but I don't think that's too big an issue.
Forms, imagemaps, and indexes don't work over
anything but HTTP either.

> Here's where I think it would be better if authors could state in the
> document itself what alternatives should be used based on a clients
> capabilities. For example, an author might want a list to be used in
> place of a table for clients w/o table support, instead of the table
> being converted to a <PRE> construct.

This is desireable, but authors mustn't be required
to write and maintain both versions of the table.

How about something like this:

<!-- in the prolog, declare which features the document uses: -->
<?HTML FEATURE tables>
<?HTML FEATURE forms>
<?HTML FEATURE imagemaps>

...

Table 1

Table 2

..

--Joe English

jenglish@crl.com